ASTM E21-13 高温拉伸的标准试验-培训讲稿
ASTM材料与实验标准.E131
Designation:E131–05Standard Terminology Relating toMolecular Spectroscopy1,2This standard is issued under thefixed designation E131;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Referenced Documents1.1ASTM Standards:3E135Terminology Relating to Analytical Chemistry for Metals,Ores,and Related MaterialsE168Practices for General Techniques of Infrared Quanti-tative AnalysisE204Practices for Identification of Material by Infrared Absorption Spectroscopy,Using the ASTM Coded Band and Chemical Classification IndexE284Terminology of AppearanceE386Practice for Data Presentation Relating to High-Resolution Nuclear Resonance(NMR)SpectroscopyE456Terminology Relating to Quality and Statistics1.2Other Documents:4ISO Guide30–1981(E)Terms and definitions used in connections with reference materials2.Terminologyabsorbance,A—the logarithm to the base10of the recip-rocal of the transmittance,(T).A5log10~1/T!52log10T(1)D ISCUSSION—In practice the observed transmittance must be substi-tuted for T.Absorbance expresses the excess absorption over that of a specified reference or standard.It is implied that compensation has been effected for reflectance losses,solvent absorption losses,and refractive effects,if present,and that attenuation by scattering is small compared with attenuation by absorption.Apparent deviations from the absorption laws(see absorptivity)are due to inability to measure exactly the true transmittance or to know the exact concentration of an absorbing substance.absorption band—a region of the absorption spectrum in which the absorbance passes through a maximum. absorption coefficient,a—a measure of absorption of radiant energy from an incident beam as it traverses an absorbing medium according to Bouguer’s law,P/P o=e−a b.D ISCUSSION—In IRS,a is a measure of the rate of absorption ofenergy from the evanescent wave.absorption parameter,a—the relative reflection loss per reflection that results from the absorption of radiant energy at a reflecting surface:a=1−R,and R=the reflected fraction of incident radiant power.absorption spectrum—a plot,or other representation,of absorbance,or any function of absorbance,against wave-length,or any function of wavelength.absorptivity,a—the absorbance divided by the product of the concentration of the substance and the sample pathlength, a=A/bc.The units of b and c shall be specified.D ISCUSSION—1—The recommended unit for b is the centimetre.Therecommended unit for c is kilogram per cubic metre.Equivalent units are g/dm3,g/L,or mg/cm3.D ISCUSSION—2—The equivalent IUPAC term is“specific absorptioncoefficient.”absorptivity,molar,e—the product of the absorptivity,a,and the molecular weight of the substance.D ISCUSSION—The equivalent IUPAC term is“molar absorption coef-ficient.”acceptance angle,n—for an opticalfiber,the maximum angle, measured from the longitudinal axis or centerline of thefiber to an incident ray,within which the ray will be accepted for transmission along thefiber by total internal reflection.D ISCUSSION—If the incidence angle exceeds the acceptance angle,optical power in the incident ray will be coupled into leaky modes or rays,or lost by scattering,diffusion,or absorption in the cladding.Fora cladded step-indexfiber in the air,the sine of the acceptance angle isgiven by the square root of the difference of the squares of the refractive indexes of thefiber core and the cladding,that is,by the relation as follows:sin A5=n122n22(2) where A is the acceptance angle and n1and n2are the refractive indexes of the core and cladding,respectively.If the refractive index is a function1This terminology is under the jurisdiction of ASTM Committee E13onMolecular Spectroscopy and Chromatography and is the direct responsibility ofSubcommittee E13.94on Terminology.Current edition approved Sept.1,2005.Published September2005.Originallyapproved st previous edition approved in2002as E131–02.2For other definitions relating to nuclear magnetic resonance,see Practice E386.3For referenced ASTM standards,visit the ASTM website,,orcontact ASTM Customer Service at service@.For Annual Book of ASTMStandards volume information,refer to the standard’s Document Summary page onthe ASTM website.4Available from American National Standards Institute(ANSI),25W.43rd St.,4th Floor,New York,NY10036.Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.of distance from the center of the core,as in the case of graded index fibers,then the acceptance angle depends on the distance from the core center.The acceptance angle is maximum at the center,and zero at the core-cladding boundary.At any radius,r,the sine of the acceptance angle of a graded indexfiber is defined in compliance with that of a step-index fiber as follows:sin A r5=n122n22(3)where Ar is the acceptance angle at a point on the entrance face at adistance,r,from the center,nr is the refractive index of the core at aradius,r,and n2is the refractive index of the cladding.In air,sin A andsin Ar are the numerical apertures.Unless otherwise stated,acceptanceangles and numerical apertures forfiber optics are those for the center of the endface of thefiber,that is,where the refractive index,and hence the numerical aperture,is the highest.accuracy—the closeness of agreement between an observed value and an accepted reference value(See Terminology E456).D ISCUSSION—The term accuracy,when applied to a set of observedvalues,will be a combination of a random component and a common systematic error or bias component.Since in routine use,random components and bias components cannot be completely separated,the reported“accuracy”must be interpreted as a combination of these two components.activefiber optic chemical sensor,n—afiber optic chemical sensor in which a transduction mechanism other than the intrinsic spectroscopic properties of the analyte is used to modulate the optical signal.D ISCUSSION—Examples include a pH sensor composed of a chemicalindicator substance whose color changes with pH,and an oxygen sensor coupled to an opticalfiber bearing a chemical indicator whose fluorescence intensity depends on oxygen concentration. aliasing—the appearance of features at wavenumbers other than their true value caused by using a sampling frequency less than twice the highest modulation frequency in the interferogram;also known as“folding.”analytical curve—the graphical representation of a relation between some function of radiant power and the concentra-tion or mass of the substance emitting or absorbing it. analytical wavelength—any wavelength at which an absor-bance measurement is made for the purpose of the determi-nation of a constituent of a sample.angle of incidence,u—the angle between an incident radiant beam and a perpendicular to the interface between two media.anti-Stokes line(band)—a Raman line(band)that has a frequency higher than that of the incident monochromatic beam.aperture of an IRE,A8—that portion of the IRE surface that can be utilized to conduct light into the IRE at the desired angle of incidence.apodization—modification of the ILS function by multiplying the interferogram by a weighting function the magnitude of which varies with retardation.D ISCUSSION—This term should strictly be used with reference to aweighting function whose magnitude is greatest at the centerburst and decreases with retardation.attenuated total reflection(ATR)—reflection that occurs when an absorbing coupling mechanism acts in the process of total internal reflection to make the reflectance less than unity.D ISCUSSION—In this process,if an absorbing sample is placed incontact with the reflecting surface,the reflectance for total internal reflection will be attenuated to some value between zero and unity(O <R<1)in regions of the spectrum where absorption of the radiant power can take place.attenuation index,k—a measure of the absorption of radiant energy by an absorbing material.k is related to the absorp-tion coefficient by:n k=a c o/4pn,where c o=the speed of light in vacuo,n=the frequency of radiant energy,and n=the refractive index of the absorbing medium. background—apparent absorption caused by anything other than the substance for which the analysis is being made. baseline—any line drawn on an absorption spectrum to estab-lish a reference point representing a function of the radiant power incident on a sample at a given wavelength.basic NMR frequency,n0—the frequency,measured in hertz (Hz),of the oscillating magneticfield applied to induce transitions between nuclear magnetic energy levels. bathochromic shift,n—change of a spectral band to longer wavelength(lower frequency)because of structural modifi-cations or environmental influence;also known as“red shift.”beamsplitter—a semireflecting device used to create,and often to recombine,spatially separate beams.D ISCUSSION—Beamsplitters are often made by depositing afilm of ahigh refractive index material onto aflat transmitting substrate with an identical compensator plate being held on the other side of thefilm. beamsplitter efficiency—the product4RT,where R is the reflectance and T is the transmittance of the beamsplitter. Beer’s law—the absorbance of a homogeneous sample con-taining an absorbing substance is directly proportional to the concentration of the absorbing substance.See also absorp-tivity.bias—a systematic error that contributes to the difference between a population mean of the measurements or test results and an accepted or reference value(see Terminology E456).D ISCUSSION—Bias is determined by the following equation:bias5e¯51n(i51n e i(4)where:n=the number of observations for which the accuracy is determined,e i=the difference between a measured value of a propertyand its accepted reference value,ande¯=the mean value of all the e i.Bouguer’s law—the absorbance of a homogeneous sample is directly proportional to the thickness of the sample in the opticalpath.D ISCUSSION—Bouguer’s law is sometimes also known as Lambert’slaw.boxcar truncation—identical effective weighting of all points in the measured interferogram prior to the Fourier transform; all points outside of the range of the measured interferogram take a value of zero.buffer—infiber optics,seefiber optic buffer.bulk reflection—reflection in which radiant energy is returned exclusively from within the specimen.D ISCUSSION—Bulk reflection may be diffuse or specular. centerburst—the region of greatest amplitude in an interfero-gram.D ISCUSSION—For unchirped or only slightly chirped interferograms,this region includes the“zero path difference point”and the“zero retardation point.”certified reference material,n—a reference material,the composition or properties of which are certified by a recognized standardizing agency or group.D ISCUSSION—A certified reference material produced by the NationalInstitute of Standards and Technology(NIST)is designated a Standard Reference Material(SRM).chemical shift(NMR),d—the defining equation for d is the following:d5Dnn R3106(5)where n R is the frequency with which the reference sub-stance is in resonance at the magneticfield used in the experiment and Dn is the frequency difference between the reference substance and the substance whose chemical shift is being determined,at constantfield.The sign of Dn is to be chosen such that shifts to the high frequency side of the reference shall be positive.D ISCUSSION—If the experiment is done at constant frequency(fieldsweep)the defining equation becomesd5Dnn R3S12Dnn RD3106(6)chirping—the process of dispersing the zero phase difference points for different wavelengths across the interferogram,so that the magnitude of the signal is reduced in the short region of the interferogram where all wavelengths would otherwise constructively interfere.clad—see cladding.cladding,n—of an opticalfiber,a layer of a optically transparent lower refractive index material in intimate con-tact with a core of higher refractive index material used to achieve total internal reflection.D ISCUSSION—The cladding confines electromagnetic waves to thecore,provides some protection to the core,and also transmits evanes-cent waves that usually are bound to waves in the core. concentration,c—the quantity of the substance contained in a unit quantity of sample.D ISCUSSION—For solution work,the recommended unit of concen-tration is grams of solute per litre of solution.core,n—of an opticalfiber,the center region of an optical waveguide through which radiant energy is transmitted.D ISCUSSION—In a dielectric waveguide such as an opticalfiber,therefractive index of the core must be higher than that of the cladding.Most of the radiant energy is confined to the core.correlation coefficient(r)—a measure of the strength of the linear relationship between X and Y,calculated by the equation:r xy5~(i51n X i Y i!~(i51n X i2!1/2~(i51n Y i2!1/2(7)where:n=the number of observations in X and Y.D ISCUSSION—Xiand Yiare any two mean corrected variables.For the simple linear regression only,r xy5R5~sign of b1!~R2!1/2(8)where:R2=the coefficient of multiple determination.critical angle,u c—the angle whose sine is equal to the relative refractive index for light striking an interface from the greater to the lesser refractive medium:u c=sin−1n21,where n21=the ratio of the refractive indices of the two media.D ISCUSSION—Total reflection occurs when light is reflected in themore refractive of two media from the interface between them at any angle of incidence exceeding the critical angle.depth of penetration,d p—in internal reflection spectroscopy, the distance into the less refractive medium at which the amplitude of the evanescent wave is e−1(that is,36.8%)of its value at the surface:d p5l12p~sin2u2h212!1/2(9)where:n21=n2/n1=refractive index of sample divided by that of the IRE;l1=l/n1=wavelength of radiant energy in the sample;and u=angle of incidence.derivative absorption spectrum—a plot of rate of change of absorbance or of any function of absorbance with respect to wavelength or any function of wavelength,against wave-length or any function of wavelength.difference absorption spectrum—a plot of the difference between two absorbances or between any function of two absorbances,against wavelength or any function of wave-length.diffuse reflection—reflection in which theflux is scattered in many directions by diffusion at or below the surface,(see Terminology E284).digitization—the conversion of an analog signal to digital values using an analog-to-digital converter“sampling”or “digital sampling.”digitization noise—the noise generated in an interferogram through the use of an analog-to-digital converter whose least significant bit represents a value comparable to,or greater than,the peak-to-peak noise level in the analog data. dilution factor—the ratio of the volume of a diluted solution to the volume of original solution containing thesamequantity of solute as the diluted solution.double modulation,n—a technique in which a modulated signal is further varied by a second means.D ISCUSSION—As an example,a spectrometer could generate a modu-lated signal while at the same time that signal is further varied by an external higher frequency modulator;on detection,the conventional spectrometric signal isfiltered out so that only the high frequency signal is recorded.double-pass internal reflection element—an internal reflec-tion element in which the radiant power transverses the length of the optical element twice,entering and leaving via the same end.effective pathlength(or effective thickness),d e—in internal reflection spectroscopy,the analog of the sample thickness in transmission spectroscopy that represents the distance of propagation of the evanescent wave within an absorbing sample in IRS.It is defined from the relationship:R=1−a d e,and is related to the absorption parameter by:a=a d e. evanescent wave—the standing wave that exists in the less refractive medium,normal to the reflecting surface of the IRE during internal reflection.extrinsicfiber optic chemical sensor,n—afiber optic chemi-cal sensor in which modulation of the optical signal is not effected through a change in the properties of thefiber itself.D ISCUSSION—Examples include a pH sensor composed of a chemicalindicator immobilized at the end of the opticalfiber,and a sensor based on Raman,fluorescence,infrared,visible,or other spectral information gathered in the acceptance cone of thefiber.far-infrared—pertaining to the infrared region of the electro-magnetic spectrum with wavelength range from approxi-mately25to1000µm(wavenumber range400to10cm-1). fast Fourier transform(FFT)—a method for speeding up the computation of a discrete FT by factoring the data into sparse matrices containing mostly zeroes.fiber optic buffer,n—material placed on or around a cladded opticalfiber to protect it from mechanical damage.D ISCUSSION—Mechanical damage can be caused by such things asmicrobends and macrobends formed during manufacture,spooling, subsequent handling,and pressure applied during use.Buffers may be bonded to the cladding and may also serve the purpose of preventing ambient energy from entering the core.fiber optic chemical sensor,n—afiber optic sensor that responds to a chemical stimulus.fiber optic sensor,n—a device that responds to an external stimulus and transmits through an opticalfiber a modulated optical signal,indicating one or more characteristics of the stimulus.D ISCUSSION—Examples include sensors which provide a suitablesignal or impulse to a meter.Such sensors might be found as the active elements in pH meters,strain gages,or pressure gages.fiber optics,n—the branch of science and technology devoted to the transmission of radiant energy throughfibers made of transparent materials.D ISCUSSION—Transparent materials include glass,fused silica,andplastic.Opticalfibers infiber optic cables may be used for data transmission,and for sensing,illumination,endoscopic,control,and display purposes,depending on their use in various geometric configu-rations,modes of excitation,and environmental conditions.Thefibers may be wound and bound in various shapes and distributions singly or in bundles.Bundles may be aligned or unaligned.Aligned bundles are often used to transmit and display images.filter—a substance that attenuates the radiant power reaching the detector in a definite manner with respect to spectral distribution.filter,neutral—afilter that attenuates the radiant power reaching the detector by the same factor at all wavelengths within a prescribed wavelength region.fixed-angle internal reflection element—an internal reflec-tion element which is designed to be operated at afixed angle of incidence.fluorescence—the emission of radiant energy from an atom, molecule,or ion resulting from absorption of a photon and a subsequent transition to the ground state without a change in total spin quantum number.D ISCUSSION—The initial andfinal states of the transition are usuallyboth singlet states.The average time interval between absorption and fluorescence is usually less than10−6s.folding—see aliasing.Fourier transform(FT)—the mathematical process used to convert an amplitude-time spectrum to an amplitude-frequency spectrum,or vice versa.D ISCUSSION—In FT-IR spectrometry,retardation is directly propor-tional to time;therefore the FT is commonly used to convert an amplitude-retardation spectrum to an amplitude-wavenumber spec-trum,and vice versa.Fourier transform infrared(FT-IR)spectrometry—a form of infrared spectrometry in which an interferogram is ob-tained;this interferogram is then subjected to a Fourier transform to obtain an amplitude-wavenumber(or wave-length)spectrum.D ISCUSSION—1—The abbreviation FTIR is not recommended.D ISCUSSION—2—When FT-IR spectrometers are interfaced withother instruments,a slash should be used to denote the interface;e.g.GC/FT-IR;HPLC/FT-IR,and the use of FT-IR should be explicit;i.e.FT-IR not IR.frequency,n—the number of cycles per unit time.D ISCUSSION—The recommended unit is the hertz(Hz)(one cycle persecond).frustrated total reflection(FTR)—the reflection which oc-curs when a nonabsorbing coupling mechanism acts in the process of total internal reflection to make the reflectance less than unity.D ISCUSSION—In the process the reflectance can vary continuouslybetween zero and unity if:(1)An optically transparent medium is within a fraction of a wavelength of the reflecting surface and its distance from the reflecting surface is changed,or(2)Both the angle of incidence and the refractive index of one of the media vary in an appropriate manner.In these cases part of the radiant power may be transmitted through the interface into the second medium without loss at the reflecting surface such that transmittance plus reflectance equals unity.It is possible,therefore to have this process taking place in some spectral regions even when a sample having absorption bands is placed in contact with the reflectingsurface.high-resolution NMR spectrometer—an NMR apparatus that is capable of producing,for a given isotope,line widths that are less than the majority of the chemical shifts and coupling constants for that isotope.D ISCUSSION—By this definition,a given spectrometer may be classedas a high-resolution instrument for isotopes with large chemical shifts, but may not be classed as a high-resolution instrument for isotopes with smaller chemical shifts.hole-burning,n—in luminescence,the photo-induced disap-pearance of a narrow segment within a broader absorption or emission band.D ISCUSSION—Holes are produced by the disappearance of resonantlyexcited molecules because of photochemical or photophysical pro-cesses.infrared—pertaining to the region of the electromagnetic spectrum with wavelength range from approximately0.78to 1000µm(wavenumber range12800to10cm-1). infrared spectroscopy—pertaining to spectroscopy in the infrared region of the electromagnetic spectrum.D ISCUSSION—1—Spectroscopy and other related terms are defined inTerminology E135.D ISCUSSION—2—Common applications of infrared spectroscopy arethe identification of materials and the quantitative analysis of materials (see,for example,Practices E204and Practices E168). instrument line shape(ILS)function—the FT of the function by which an interferogram is weighted.D ISCUSSION—This weighting may be performed optically,due to thefinite optical throughput,or digitally,through multiplication by an apodization function,or both.The ILS function is the profile of the spectrum of a monochromatic source producing a beam with the same throughput as the beam in the actual measurement being performed. instrument response time—the time required for an indicat-ing or detecting device to undergo a defined displacement following an abrupt change in the quantity being measured. integration period,p—the time,in seconds,required for the pen or other indicator to move98.6%of its maximum travel in response to a step function.D ISCUSSION—For instruments with afirst-order response,the integra-tion period will be approximately equal to four times the exponential time constant.It is equal to the period,classically defined,for a second order,critically damped response system.intercorrelation coefficient,(r XX)—a measure of the linear association between values of the same type of variable expressed as a correlation coefficient,(r).D ISCUSSION—The variables X and Y are replaced by Xj and Xkin theequation for the correlation coefficient,r.interferogram,I(d)—record of the modulated component of the interference signal measured as a function of retardation by the detector.D ISCUSSION—1—An alternate symbol is I(x).D ISCUSSION—2—The recommended symbol for the spectrum com-puted from I(d)is B(n).An alternate symbol is B(s). interferogram,double-sided—interferogram measured with approximately equal retardation on either side of the center-burst.interferogram,laser reference—sinusoidal interferogram of a laser source measured at the same time as the signal interferogram.D ISCUSSION—The zero crossings of this interferogram are used tocontrol sampling of the signal interferogram.It may also be noted that other effectively monochromatic sources can be used in place of the laser.interferogram,signal—interferogram of the beam of radiant energy whose spectrum is desired.interferogram,single-sided—interferogram in which sam-pling is initiated close to the centerburst and continues through that point to the maximum retardation desired. interferogram,white light—reference interferogram of a broadband light source measured at the same time as the signal interferogram and used to initiate data acquisition of consecutive scans for signal-averaging. interferometer—device used to divide a beam of radiant energy into two or more paths,generate an optical path difference between the beams,and recombine them in order to produce repetitive interference maxima and minima as the optical retardation is varied.interferometer,Genzel—interferometer in which the beam is focused in the plane of the beamsplitter and collimated before the moving mirror(s).interferometer,lamellar grating—interferometer in which the beam is reflected from two interleaved mirrors,one of which is stationary while the other is movable.D ISCUSSION—This type of interferometer is generally used only forfar infrared spectrometry.interferometer,Michelson—interferometer in which an ap-proximately collimated beam of radiant energy is divided into two paths by a beamsplitter;one beam is reflected from a movable mirror and the other from a stationary mirror,and they are then recombined at the beamsplitter. interferometer,rapid-scanning—interferometer in which the retardation is varied rapidly enough that the modulation frequencies in the interferogram are sufficiently high that the interferogram signal can be amplified directly without addi-tional modulation by an external chopper. interferometer,refractively scanned—interferometer in which the retardation between two beams is generated by the movement of a wedged optical element. interferometer,slow-scanning—interferometer in which the retardation is continuously varied,but so slowly that an external chopper is needed to modulate the beam at a frequency which is high enough for ac signal amplification. interferometer,stepped-scanning—interferometer in which the movable element is held stationary for the length of time required for signal integration and digitization of each sample point,and then translated to the next sample point. internal conversion,n—a transition between electronic states of the same total spin quantum number(multiplicity). internal,reflection attachment,IRA—the transfer optical system which supports the IRE,directs the energy of the radiant beam into the IRE,and then redirects the energy into the spectrometer or onto the detector.The IRA may bepartof an internal reflection spectrometer or it may be placed into the sampling space of a spectrometer.internal reflection element(IRE)—the transparent optical element used in internal reflection spectroscopy for estab-lishing the conditions necessary to obtain the internal reflec-tion spectra of materials.D ISCUSSION—Radiant power is propagated through it by means ofinternal reflection.The sample material is placed in contact with the reflecting surface or it may be the reflecting surface itself.If only a single reflection takes place from the internal reflection element the element is said to be a single reflection element;if more than one reflection takes place,the element is said to be a multiple reflection element.When the element has a recognized shape it is identified according to each shape,for example,internal reflection prism,internal reflection hemicylinder,internal reflection plate,internal reflection rod, internal reflectionfiber,etc.internal reflection spectroscopy(IRS)—the technique of recording optical spectra by placing a sample material in contact with a transparent medium of greater refractive index and measuring the reflectance(single or multiple)from the interface,generally at angles of incidence greater than the critical angle.intersystem crossing—-a transition between electronic states that differ in total spin quantum number(multiplicity).D ISCUSSION—Current experimental evidence indicates this process isnonradiative.intrinsicfiber optic chemical sensor,n—afiber optic chemi-cal sensor in which the modulation of the optical signal is effected through a change in the properties of the optical fiber itself,and such modulation occurs while the radiant energy is guided by the opticalfiber.irreversiblefiber optic chemical sensor,n—afiber optic chemical sensor that undergoes a permanent depletion or degradation of the transduction element as a result of the transduction process.D ISCUSSION—An example is a sensor based on an indicator that reactsirreversibly with the target analyte and that cannot be replenished after measurement.isoabsorptive point—a wavelength at which the absorptivities of two or more substances are equal.isosbestic point—the wavelength at which the absorptivities of two substances,one of which can be converted into the other,are equal.isostilbic point,n—in luminescence,the wavelength at which the intensity of emission of a sample does not change during a physical interaction or chemical reaction.level one(1)test,n—a simple series of measurements de-signed to provide quantitative data on various aspects of instrument performance and information on which to base the diagnosis of problems.level zero(0)test,n—a routine check of instrument perfor-mance,that can be done in a few minutes,designed to virtually detect significant changes in instrument perfor-mance and provide a database to determine instrument function over time.linear dispersion—the derivative,d x/d l,where x is the distance along the spectrum,in the plane of the exit slit,and l is the wavelength.lock signal(NMR)—the NMR signal used to control the field-frequency ratio of the spectrometer.It may or may not be the same as the reference signal. luminescence—the emission of radiant energy during a tran-sition from an excited electronic state of an atom,molecule, or ion to a lower electronic state.D ISCUSSION—1—The recommended unit for“sample pathlength”iscentimetres.This distance does not include the thickness of the walls of any absorption cell in which the specimen is contained.D ISCUSSION—2—In strict usage,a more appropriate term would be“specimen pathlength.”This is currently under advisement by E13. mid-infrared—pertaining to the infrared region of the elec-tromagnetic spectrum with wavelength range from approxi-mately2.5to25µm(wavenumber range4000to400cm-1). modulate,v—to vary a characteristic or parameter of an entity in accordance with a characteristic or parameter of another entity.modulation frequency,f v—the frequency,in Hz,at which radiant energy of a given wavenumber is modulated by a rapid-scanning interferometer.D ISCUSSION—1—This is given by the product of the wavenumber(cm−1)and the rate of change of retardation(cm·s−1).D ISCUSSION—2—An alternate symbol is fo.molar absorptivity,e—see absorptivity,molar. monochromator—a device or instrument that,with an appro-priate energy source,may be used to provide a continuous calibrated series of electromagnetic energy bands of deter-minable wavelength or frequency range.multiple correlation coefficient,(R)—the correlation,r yyˆ, between the accepted reference values,Y i,and the values determined using the calibration equation,Yˆi,equal to the square root of the coefficient of multiple determination,R2. near-infrared—pertaining to the infrared region of the elec-tromagnetic spectrum with wavelength range from approxi-mately0.78to2.5µm(wavenumber range12800to4000 cm-1).neutralfilter—seefilter,neutral.NMR absorption band;NMR band—a region of the spec-trum in which a detectable signal exists and passes through one or more maxima.NMR absorption line—a single transition or a set of degen-erate transitions is referred to as a line.NMR apparatus;NMR equipment—an instrument compris-ing a magnet,radio-frequency oscillator,sample holder,and a detector that is capable of producing an electrical signal suitable for display on a recorder or an oscilloscope,or which is suitable for input to a computer.nuclear magnetic resonance(NMR)spectroscopy—that form of spectroscopy concerned with radio-frequency-induced transitions between magnetic energy levels of atomic nuclei.numerical aperture(NA),n—the sine of one half of the vertex angle of the largest cone of meridional rays that can enter or leave an optical system or element,multiplied by the refractive index of the medium in which the cone is located.D ISCUSSION—Numerical aperture is generally measured with respectto an image point and will vary as that point is moved.For anoptical。
ASTME21-13高温拉伸的标准试验-培训讲稿
设备要求-----加热装置
除非双方事先特 意商定其他介质， 否则均应用电阻 丝炉或辐射炉在 大气气氛中加热
试样。
试验期间（从加力到断裂的时间）， 指示温度与标称温度之差不应超过
下列限度：
≤ 1000 ℃，± 3 ℃
＞可能使温度升 高超过上述规定范围。在这种情况 下，报告中应包括最大负荷时的温
ASTM E21-20 13 金属材料 高温拉伸的试验方法
编制：卢小成 2015年七月
适用范围
几个术语
试样的小截面段是横截面比夹持两端部小的试样长度中间部分，其横截面是均匀的。 小截面段的长度是形成缩减部分边界两过渡圆弧的两切点之间的距离。 小截面段的调节长度是比缩减部分的长度长出一个用来补偿过渡弧区的应变计算值 标距是标在试样上两标记之间用于测定断后延伸率的原始距离. 轴向应变是在相对两侧并与试样轴等距离处所测量的应变之平均值 最大弯曲应变是在试样的最小截面段上弯曲应变的最大值。它可以从两个不同的纵向位置在每个位置上取三个圈向位置 测得的应变计算得到。
度和过冲的理由。
设备要求-----温度测量装置
试验期间（从加力到断裂的时间），指示温度与标称温度之差不应超过下列限度：≤ 1000 ℃，± 3 ℃ ＞ 1000 ℃，± 6 ℃
应用与电位计或毫伏计相连接的热电偶进行温度测量 应使用标定过的热电偶测量温度
• 用来制作贱金属热电偶的金属丝的每一批中标定代表性的热电偶 • 除相当低的使用温度外，重新使用贱金属热电偶会带来误差，除非重现最初使用时的深
铸造试样
• 对直径、平直度和同心度规定办不到时，应尽可能接近这些要求 • 如果试样不符合尺寸要求，试验报告应如实注明并报告偏差大小
标定与标准化
需标定和校准的项目
ASME标准培训大纲(拉伸、弯曲)
CV取证试验ASME标准培训大纲（仅针对板材焊接）一、培训方法从模拟试验的整个过程着手，对试验过程涉及到的ASME标准熟练应用。
二、培训内容1、试验样品的收样试样满足ASME第IX卷中QW-151中规定，拉伸试样：满足QW-462.1(a)中规定弯曲试样：满足QW462.2中规定。
2.试验试验操作者应穿工作服进入操作室，并观察记录操作室温度。
2.1拉伸试验：夹持装置:试样的轴线应与试验机夹头中心线重合。
实验步骤：（1）试验机启动前应检察试验机启动后将其预热到正常的操作温度。
（2）试样尺寸测量：横截面尺寸等于或者大于5mm的拉伸试样尺寸应测量并记录精确值0.02mm。
（3）应使夹持部分足够长，以便试样伸进夹具的距离等于或大于夹具长度的三分之二。
（4）加载：根据ASME E8中7.6.4规定试验机的速度应设定在每分钟缩减部分长度（或对于没有紧缩的夹具间距离）的0.05到0.5mm/mm/min之间，直至试样断裂。
（5）卸载，取下试样并计算强度。
抗拉强度的计算时试样极限总载荷除以加载前通过实测计算的最小横截面积。
试验值小于500MPa，修约精确到1 MPa，试验值在500 MPa~1000 MPa，修约精确到5 MPa。
2.2.弯曲试验：实验步骤（1）弯头直径及支辊间距的确定：按照ASME第IX卷中QW466.1及QW466.2中要求选择弯头及设置支辊间距。
（2）加载：弯曲试验在恒定速率下弯至试样的曲率达到QW466.1所示压模与试样之间插不进3.2mm直径的金属丝为止，此过程在15s至2min之内完成。
（3）卸载取下试验后试样并观察判定。
3.结果的判定3.1拉伸试验：满足ASME IX 中QW-153中规定：a. 试样的抗拉强度不小于母材规定最小的抗拉强度；b.焊缝金属的规定最小抗拉强度，此条适用于有关卷允许使用室温低于母材的焊缝金属；如果试样断在焊缝或焊缝界面以外的母材上，只要强度低于母材最小抗拉强度的量不超过5%，可认为试验满足要求。
金属材料室温拉伸试验方法标准培训讲稿75页PPT
45、自己的饭量自己知道。——苏联
金属材料室温拉伸试验方法标准培训 讲稿
16、人民应该为法律而战斗，就像为 了城墙 而战斗 一样。 ——赫 拉克利 特 17、人类对于不公正的行为加以指责 ，并非 因为他 们愿意 做出这 种行为 ，而是 惟恐自 己会成 为这种 行为的 牺牲者 。—— 柏拉图 18、制定法律法令，就是为了不让强 者做什 么事都 横行霸 道。— —奥维 德 19、法律是社会的习惯和思想的结晶 。—— 托·伍·威尔逊 20、人们嘴上挂着的法律，其真学问是异常珍贵的东西，从任何源泉吸 收都不可耻。——阿卜·日·法拉兹
42、只有在人群中间，才能认识自 己。——德国
43、重复别人所说的话，只需要教育； 而要挑战别人所说的话，则需要头脑。—— 玛丽·佩蒂博恩·普尔
拉伸试验国家标准ppt培训课件.ppt
新版本标准，附有A、B、C、D、E、F、G、 H、I、J、K、L等12个附录。
其中A、B、C、D为“标准的附录”，规定了不同厚度、直 径的板材、棒材、型材、管材进行拉伸试验时的试样类型; 其余为“提示的附录”
力学性能符号的变更
用“Ｒ”取代“σ”表示应力和强度的主符号; 用“Ａ”取代“δ”表示伸长率主符号; 用“Ｚ”取代“ψ”表示断面收缩率。
“点”和“应力”改为“强度”
常用屈服点的“点”及规定伸长应力的“应力”均改为 “强度”;
规定非比例伸长应力改为规定非比例延伸强度。
新版本标准对“伸长”和“延伸”作了区别。
应从总延伸中扣除弹性延伸部分。
原则上,断裂发生在引伸计标距以内方为有效,但断后伸长 率等于或大于规定值,不管断裂位置处于何处测量均为有 效。
Hale Waihona Puke 为了避免因发生在规定的范围以外的断裂而造成 试样报废,可以采用附录Ｆ的移位方法测定断后伸 长率。
将测定的断裂总延伸除以试样原始标距得到断裂 总伸长率。
规定非比例延伸强度、规定总延伸强度、规定残 余延伸强度,以及规定残余延伸强度的验证试验,应 使用不劣于1级准确度的引伸计;测定其他具有较 大延伸率的性能,例如抗拉强度、最大力总延伸率 和最大力非比例延伸率、断裂总伸长率,以及断后 伸长率,应使用不劣于2级准确度的引伸计。
万能材料试验机
电脑伺服控制精密万能材料试验机
1.2 可测量的量: 伸长率:断后伸长率(A),断裂总伸长率(At),最
大力总伸长率(Agt),最大力非比例伸长率(Ag), 屈服点延伸率(Ae)等的测定.
强度:上屈服强度(ReH),下屈服强度(Rel),规 定非比例延伸强度(Rp),规定总延伸强度(Rt), 抗拉强度(Rm)的测定.
astm e21-2020金属材料的高温拉伸试验方法
astm e21-2020金属材料的高温拉伸试验方法ASTM E21-2020标准是关于金属材料在高温下进行拉伸试验的方法。
高温拉伸试验是一种常用的测试方法，用于评估材料在高温环境下的性能和可靠性。
本文将简要介绍ASTM E21-2020标准的背景、目的和试验过程，并简要介绍一些与高温拉伸试验相关的考虑因素。
首先，让我们来了解ASTM E21-2020标准的背景和目的。
这个标准是由美国材料与试验协会（ASTM International）制定的，旨在提供一种标准化的方法来测量金属材料在高温下的拉伸性能。
高温拉伸测试是金属材料研究和应用中非常重要的一部分，因为许多金属材料在高温环境下会发生变形、破裂或失去性能。
ASTM E21-2020标准主要包括以下几个方面的内容。
首先是试样的选择和制备。
试样的选择要考虑到材料类型、尺寸、形状等因素，以及试验过程中受到的应力和温度。
试样的制备要符合标准中给出的要求，确保试样的准确性和可重复性。
其次是试验设备和条件的设置。
ASTM E21-2020标准详细描述了拉伸试验设备的要求，包括拉伸机、温度控制系统、试样夹具等。
试验条件的设置包括试样的初始长度、加载速率、试验温度等。
这些条件设计要符合要求，以确保试验结果的准确性和可比性。
接下来是试验过程的描述。
ASTM E21-2020标准规定了在高温下进行拉伸试验的步骤和要点。
首先，试样被夹持在拉伸机上，然后通过加载系统施加拉力。
试验过程中需要记录试样的变形、载荷和温度等数据。
试验结束后，可以根据这些数据计算和评估材料的力学性能，如强度、延伸率、模量等。
最后，ASTM E21-2020标准还提供了试验结果的分析和报告要求。
试验结果可以通过统计分析和图表展示，以便更好地理解材料的性能。
试验报告需要包括试验的目的、方法、结果和结论等内容，以便他人能够理解和评估试验过程和结果。
在进行高温拉伸试验时，还需要考虑一些其他因素。
首先是温度控制。
金属材料的高温拉伸试验方法
金属材料的高温拉伸试验方法1. 引言金属材料在高温环境下的性能表现与常温下有很大的差异，因此需要进行高温拉伸试验来评估其其在高温下的强度、塑性和断裂行为等特性。
本文将介绍一种常用的高温拉伸试验方法。
2. 试样制备首先，需要准备符合要求的试样。
试样一般采用圆柱形状，长度大于直径，以保证试样在拉伸时的充分变形。
试样的制备材料应与待测试的金属材料相同，尺寸应符合试验要求。
3. 试验设备高温拉伸试验需要借助一些专用的设备，如高温拉伸试验机和加热炉。
高温拉伸试验机具备高温环境下能够施加合适加载的能力，并能记录试样的应力和变形。
加热炉则提供稳定的高温环境。
4. 试验条件设定在进行高温拉伸试验之前，需要设定试验的温度、试样加载速度和试验条件。
温度是高温拉伸试验的重要参数之一，需要根据待测试金属材料的使用环境和要求进行选择，并在试验中保持恒定。
加载速度的选择应能够保证试样在整个试验过程中能够产生足够的塑性变形，并保持一定的加载速率以获得准确的数据。
试验条件的设定需要遵循相应的标准或规范。
5. 试验过程在试验开始之前，需要将试样装夹在试验机上，并预热到设定温度，以保证整个试验过程在稳态下进行。
然后，通过试验机施加纵向拉伸力，逐渐增加载荷来对试样进行拉伸。
试验机会实时记录试样的应力和变形，并通过标准的试验曲线来判断试样的力学性能。
6. 数据处理在试验结束后，需要对试验数据进行处理。
常见的数据处理方法包括计算试样的屈服强度、抗拉强度和延伸率等力学性能指标。
此外，还可以绘制应力-应变曲线来分析试样的拉伸过程。
7. 结果分析根据试验数据和处理结果，可以对金属材料在高温下的力学性能进行评估。
如抗拉强度、屈服强度、断裂延伸率等。
8. 结论通过以上步骤，我们可以得到金属材料的高温拉伸性能参数，并对其在高温环境下的应用进行评估。
这有助于了解金属材料在高温下的性能表现，并为实际工程应用提供依据。
总结：金属材料的高温拉伸试验是评估材料在高温环境下性能的有效手段。
ASTM E21-13 高温拉伸的标准试验-培训讲稿
不要求测定屈服强度时
除非已知引伸计对室温变化不敏感，只要引伸计已装卡，室温的温度变化范围不应超过 6 ℃
取样要求
取自代表该批材料的部位
从最终状态的材料切取样 坯。每批做一次试验
一批相同炉号、相同标称 尺寸和相同状态（特征） 的材料
试样和样坯
总体要求
•试样尺寸及其形状应以得到待检验材料的代表性试样为基础
试样位置和方向
对于容易受其环境（例如金属在空气中氧化）浸蚀的材料高温拉伸试验， 可以把试样封闭在容器内，使之能够在真空或惰性气氛中进行试验。
设备要求-----加热装置
除非双方事先特 意商定其他介质， 否则均应用电阻 丝炉或辐射炉在 大气气氛中加热 试样。
试验期间（从加力到断裂的时间）， 指示温度与标称温度之差不应超过 下列限度：
当有可能时，应把引伸计直接装卡到试样的缩减部分
将引伸计安装在小试样上可能难以实行。在这种情况下，可记录试样两夹头或十字头的分离移动，并用 此来测定与 0.2% 偏置量屈服强度相应的应变。这样得到数值的精确度较低，因而必须注明为“近似屈服 强度”。观测到的伸长应通过 9.6.3 和 10.1.3 条所叙述的程序进行修正
• 试样的取向应使试样轴线平行于加工方向 •厚度、直径或两面间的距离等于或小于 38 毫米的产品在中心部位 •厚度、直径或两面间的距离大于 38 毫米的产品，在产品的中心至其表面的中间部位
ห้องสมุดไป่ตู้
ASTM E112-2013 测定平均晶粒度的标准试验-培训讲稿
十二、统计分析
a.单个视场中的
或
的平均值
式中，Xi表示单个视场的值 b.计算单次测量的标准偏差 c.计算每次测量95%的置信区间，95%CI=
d.百分比的相对精度 一条原则：10%RA（或以下）对大多数用途 来说被认为是可接受的精确度。
95%置信度内部乘法因子
视场数，n 5 6 7 8 9 10 11 12 t 2.776 2.571 2.447 2.365 2.306 2.262 2.228 2.201 视场数，n 13 14 15 16 17 18 19 20 t 2.179 2.160 2.145 2.131 2.120 2.110 2.101 2.093
七、比较法
适用于等轴晶粒的完全再结晶的材料或铸 态材料。 除非标准的图谱与试样的很接近，否则便 会出现误差。 四种图谱 图片Ⅰ---无孪晶的晶粒(无反差浸蚀） 图片Ⅱ---有孪晶的晶粒(无反差浸蚀） 图片Ⅲ---有孪晶的晶粒(反差浸蚀） 图片Ⅳ---钢中奥氏体晶粒
比较法使用推荐表
适用性 推荐用于均一等轴形状不一致的所有组织。 对于各向异性的组织，截距法可用来分别 评定三个主要方向上的尺寸，或者合理地 评定平均尺寸。 平均线性截距 和平均晶粒面积之间的关系
ASTM晶粒度级数G和平均线性截距的关系如 下
式中： 为32mm, 和 为放大1倍时的毫 米数或宏观测定的晶粒度级数时的每毫米数 的截距数或是微观测定的晶粒度级别时在放 大100倍视场上的毫米值。 注：对于宏观(微观）测定的晶粒度级数 ASTM No.0（在放大100倍观察的视场上）的 平均截距尺寸正好等于32mm
3、截距法 截距法包括了被一根检测线截取的晶 粒数，或晶界与一根检测线，单位长 度检测线相交数的实际计数，用于计 算平均截距长度。 截距法复测准确性和再现性小于±0.5 级的晶粒度单位。 对于同样精确度水平，截距法要快于 面积计算法
【大学】金属材料室温拉伸试验辅导讲义
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试验机的检测/校准项目及相关 要求
1级试验机示值进回程相对误差u u=（ Fi′-Fi）/F ≤1.5% ′ F—测力仪指示力， Fi—试验机指示力， Fi —卸载时试验机指示力， 如果1000N的1级试验机，标定时测力计
4．显示部分 绘拉伸图 显示力值及变形值及计算
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电子万能试验机
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电子万能试验机
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B．液压万能试验机的基本结构、 工作环境、操作技术与维修保养
1．加力部分： 试验机底座1装有两根固定立柱2，立柱支撑着固定横
梁3及工作油缸4。开动油泵电机后，电动机带动油泵5， 将油箱里的油经送油阀22送至工作油缸4，推动工作活 塞6，使上横梁7、活动立柱8和活动平台9向上移动。 如将拉伸试样装于上夹头10和下夹头11内，当活动平 台向上移动时，因下夹头不动，上夹头随着平台向上 移动，则试样受到拉伸，如将试样放在平台的承压座 12内，平台上升时，试样则受到压缩。 做拉伸试验时，为了适应不同长度的试样，可开动 下夹头的电机使之带动蜗杆，蜗杆带动涡轮，涡轮再 带动丝杠，可控制下夹头上、下移动，调整适当的拉 伸空间。
（2）力学性能 材料在力作用下显示的 与弹性和非弹性反应相关或包含应力-应 变关系的性能
（3）力学试验 测定力学性能的试验
.
（4）弹性模量：轴向拉伸应力与轴向拉 伸应变成线性比例关系阶段中，拉伸应 力与拉伸应变之比。（低于比例极限的 应力与相应应变的比值）
（5）横向应变 垂直于施加力方向的线 性应变量
±1N内合格。
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试验机的检测/校准项目及相关 要求
相对分辨力α
1级试验机α =（γ/F ） ×100%≤0.5%
ASTM E8-13 测定拉伸试验的标准试验-培训讲稿
五、取样和制备要求
对于厚度、直径或平面间距小于或等于40mm的产 品在中心位置取样。 对于厚度、直径或平面间距大于40mm的产品在中 心至表面的中间位置取样。 试样加工过程中，必须保证试验结果的最大精确度 和最小的偏差。 制备缩减段时，应避免冷加工、缺口、刀痕、毛刺、 粗糙表面或边角、过热或其他对性能测量造成有害 的影响。 对于脆性材料，标距两端应使用半径大的过渡圆弧 试样表面光洁度应按适用的产品标准规定
屈服特性的试验速度
屈服特性可包括屈服强度和屈服点伸长。 除非另有规定，任何常规试验速度可使用 至规定屈服强度一半或规定抗拉强度四分 之一，以其中最小者为准。在这一点以上 的速度应在规定的范围内。 如果用来确定屈服强度、屈服点伸长、抗 拉强度和断面收缩率时要求不同速度范围， 应在产品标准中说明。
二、术语
抗拉强度：材料所能承受的最大抗拉应力 屈服强度： 上屈服强度：轴向试验中，伴随不连续屈服首 次出现的应力最大值（首次出现拐点时的应 力）。 下屈服强度：轴向试验中，在不考虑瞬时效应 的情况下，不连续屈服过程中记录的最小应力。 *仲裁试验：为解决对规定要求的符合性的不一 致而执行的试验，或者由第三方执行的试验。
13报告屈服强度和抗拉强度试验值修约按e29试验值500mpa修约精度到1mpa500mpa试验值1000mpa修约精度到5mpa试验值大于等于1000mpa修约精确到10mpa14原试样机加工表面差原试样尺寸错误由于机加工操作有误使试样的性能发生改试验方法有误断裂在标距之外测伸长率时断在标距中心一半以外试验设备运行不正常15所用的参考标准即e8和e8m材料和样品特征试样种类屈服强度和确定屈服强度的方法屈服点伸长抗拉强度伸长率如有要求均匀伸长率或面积的缩减试样试验部分尺寸用来计算取自大直径管产品试样横截面积的公式用来测试试验的速度和方法用来修约试验结果的方法更换试样的原因结束后清洗和维护按制造商规范和说明执行试验机的清洗和日常维护
ASTM_E21-05高温拉伸(用于CV)
Designation:E 21–05Standard Test Methods forElevated Temperature Tension Tests of Metallic Materials 1This standard is issued under the fixed designation E 21;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon (e )indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1These test methods cover procedure and equipment for the determination of tensile strength,yield strength,elongation,and reduction of area of metallic materials at elevated tempera-tures.1.2Determination of modulus of elasticity and proportional limit are not included.1.3Tension tests under conditions of rapid heating or rapid strain rates are not included.1.4The values stated in SI units are to be regarded as the standard.1.5This standard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents 2.1ASTM Standards:2E 4Practices for Force Verification of Testing Machines E 6Terminology Relating to Methods of Mechanical Test-ingE 8Test Methods for Tension Testing of Metallic Materials E 29Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationE 74Practice for Calibration of Force Measuring Instru-ments for Verifying the Force Indication of Testing Ma-chinesE 83Practice for Verification and Classification of Exten-someters SystemE 177Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE 220Test Method for Calibration of Thermocouples byComparison TechniquesE 633Guide for Use of Thermocouples in Creep and Stress Rupture Testing to 1800°F (1000°C)in AirE 691Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3.Terminology 3.1Definitions:3.1.1Definitions of terms relating to tension testing which appear in Terminology E 6,shall apply to the terms used in this test method.3.2Definitions of Terms Specific to This Standard:3.2.1reduced section of the specimen —the central portion of the length having a cross section smaller than the ends which are gripped.The cross section is uniform within tolerances prescribed in 7.7.3.2.2length of the reduced section —the distance between tangent points of the fillets which bound the reduced section.3.2.3adjusted length of the reduced section is greater than the length of the reduced section by an amount calculated to compensate for strain in the fillet region (see 9.2.3).3.2.4gage length —the original distance between gage marks made on the specimen for determining elongation after fracture.3.2.5axial strain —the average of the strain measured on opposite sides and equally distant from the specimen axis.3.2.6bending strain —the difference between the strain at the surface of the specimen and the axial strain.In general it varies from point to point around and along the reduced section of the specimen.3.2.7maximum bending strain —the largest value of bend-ing strain in the reduced section of the specimen.It can be calculated from measurements of strain at three circumferential positions at each of two different longitudinal positions.4.Significance and Use 4.1The elevated-temperature tension test gives a useful estimate of the ability of metals to withstand the application of applied tensile ing established and conventional relationships it can be used to give some indication of probable behavior under other simple states of stress,such as compres-sion,shear,etc.The ductility values give a comparative measure of the capacity of different materials to deform locally1These test methods are under the jurisdiction of ASTM Committee E28on Mechanical Testing and are the direct responsibility of Subcommittee E28.04on Uniaxial Testing.Current edition approved June 1,2005.Published June 2005.Originally approved in st previous edition approved in 2003as E 21–03a.2For referenced ASTM standards,visit the ASTM website,,or contact ASTM Customer Service at service@.For Annual Book of ASTM Standards volume information,refer to the standard’s Document Summary page on the ASTM website.Copyright ©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.引用文件术语意义和用途金属材料高温拉伸的标准测试方法without cracking and thus to accommodate a local stress concentration or overstress;however,quantitative relationships between tensile ductility and the effect of stress concentrations at elevated temperature are not universally valid.A similar comparative relationship exists between tensile ductility and strain-controlled,low-cycle fatigue life under simple states of stress.The results of these tension tests can be considered as only a questionable comparative measure of the strength and ductility for service times of thousands of hours.Therefore,the principal usefulness of the elevated-temperature tension test is to assure that the tested material is similar to reference material when other measures such as chemical composition and microstructure also show the two materials are similar.5.Apparatus 5.1TestingMachine :5.1.1The accuracy of the testing machine shall be within the permissible variation specified in Practices E 4.5.1.2Precaution should be taken to assure that the force on the specimens is applied as axially as possible.Perfect axial alignment is difficult to obtain especially when the pull rods and extensometer rods pass through packing at the ends of the furnace.However,the machine and grips should be capable of loading a precisely made specimen so that the maximum bending strain does not exceed 10%of the axial strain,when the calculations are based on strain readings taken at zero force and at the lowest force for which the machine is being qualified.N OTE 1—This requirement is intended to limit the maximum contribu-tion of the testing apparatus to the bending which occurs during a test.It is recognized that even with qualified apparatus different tests may have quite different percent bending strain due to chance orientation of a loosely fitted specimen,lack of symmetry of that particular specimen,lateral force from furnace packing,and thermocouple wire,etc.The scant evidence available at this time 3indicates that the effect of bending strain on test results is not sufficient,except in special cases,to require the measurement of this quantity on each specimen tested.5.1.2.1In testing of brittle material even a bending strain of 10%may result in lower strength than would be obtained with improved axiality.In these cases,measurements of bending strain on the specimen to be tested may be specifically requested and the permissible magnitude limited to a smaller value.5.1.2.2In general,equipment is not available for determin-ing maximum bending strain at elevated temperatures.The testing apparatus may be qualified by measurements of axiality made at room temperature using the assembled machine,pull rods,and grips used in high temperature testing.The specimen form should be the same as that used during the elevated-temperature tests and designed so that only elastic strains occur throughout the reduced section.This requirement may neces-sitate use of a material different from that used during the elevated-temperature test.See Practice E 1012for recom-mended methods for determining specimen alignment.5.1.2.3Gripping devices and pull rods may oxidize,warp,and creep with repeated use at elevated temperatures.Increasedbending stresses may result.Therefore,grips and pull rods should be periodically retested for axiality and reworked when necessary.5.1.3The testing machine shall be equipped with a means of measuring and controlling either the strain rate or the rate of crosshead motion or both to meet the requirements in 9.6.5.1.4For high-temperature testing of materials that are readily attacked by their environment (such as oxidation of metal in air),the specimen may be enclosed in a capsule so that it can be tested in a vacuum or inert gas atmosphere.When such equipment is used,the necessary corrections must be made to determine the actual forces seen by the specimen.For instance,compensation must be made for differences in pres-sures inside and outside of the capsule and for any variation in the forces applied to the specimen due to sealing ring friction,bellows or other features.5.2Heating Apparatus :5.2.1The apparatus for and method of heating the speci-mens should provide the temperature control necessary to satisfy the requirements specified in 9.4.5.2.2Heating shall be by an electric resistance or radiation furnace with the specimen in air at atmospheric pressure unless other media are specifically agreed upon in advance.N OTE 2—The media in which the specimens are tested may have a considerable effect on the results of tests.This is particularly true when the properties are influenced by oxidation or corrosion during the test.5.3Temperature-Measuring Apparatus :5.3.1The method of temperature measurement must be sufficiently sensitive and reliable to ensure that the temperature of the specimen is within the limits specified in 9.4.4.5.3.2Temperature should be measured with thermocouples in conjunction with the appropriate temperature indicating instrumentation.N OTE 3—Such measurements are subject to two types of error.Ther-mocouple calibration and instrument measuring errors initially introduce uncertainty as to the exact temperature.Secondly both thermocouples and measuring instruments may be subject to variation with mon errors encountered in the use of thermocouples to measure temperatures include:calibration error,drift in calibration due to contamination or deterioration with use,lead-wire error,error arising from method of attachment to the specimen,direct radiation of heat to the bead,heat-conduction along thermocouple wires,etc.5.3.3Temperature measurements should be made with ther-mocouples of known calibration.Representative thermo-couples should be calibrated from each lot of wires used for making base-metal thermocouples.Except for relatively low temperatures of exposure,base-metal thermocouples are sub-ject to error upon reuse,unless the depth of immersion and temperature gradients of the initial exposure are reproduced.Consequently base-metal thermocouples should be verified by the use of representative thermocouples and actual thermo-couples used to measure specimen temperatures should not be verified at elevated temperatures.Base-metal thermocouples also should not be reused without clipping back to remove wire exposed to the hot zone and rewelding.Any reuse of base-metal thermocouples after relatively low-temperature use with-out this precaution should be accompanied by recalibration3Subcommittee E28.10on Effect of Elevated Temperature on Properties requests factual information on the effect of nonaxiality of loading on test results.设备data demonstrating that calibration was not unduly affected by the conditions of exposure.5.3.3.1Noble metal thermocouples are also subject to errors due to contamination,etc.,and should be periodically annealed and verified.Thermocouples should be kept clean prior to exposure and during use at elevated temperatures.5.3.3.2Measurement of the emf drift in thermocouples during use is difficult.When drift is a problem during tests,a method should be devised to check the readings of the thermocouples on the specimen during the test.For reliable calibration of thermocouples after use the temperature gradient of the testing furnace must be reproduced during the recalibra-tion.5.3.4Temperature-measuring,controlling,and recording in-struments should be verified periodically against a secondary standard,such as a precision potentiometer and if necessary re-calibrated.Lead-wire error should be checked with the lead wires in place as they normally are used.5.4Extensometer System :5.4.1Practice E 83,is recommended as a guide for selecting the required sensitivity and accuracy of extensometers.For determination of offset yield strength at 0.1%or greater,a Class B-2extensometer may be used.The extensometer should meet the requirements of Practice E 83and should,in addition,be tested to assure its accuracy when used in conjunction with a furnace at elevated temperature.One such test is to measure at elevated temperature the stress and strain in the elastic range of a metal of known modulus of binations of stress and temperature which will result in creep of the specimen during the extensometer system evaluation should be avoided.N OTE 4—If an extensometer of Class B-2or better is attached to the reduced section of the specimen,the slope of the stress-strain curve will usually be within 10%of the modulus of elasticity.5.4.2Non-axiality of loading is usually sufficient to cause significant errors at small strains when strain is measured on only one side of the specimen.4Therefore,the extensometer should be attached to and indicate strain on opposite sides of the specimen.The reported strain should be the average of the strains on the two sides,either a mechanical or electrical average internal to the instrument or a numerical average of two separate readings.5.4.3When feasible the extensometer should be attached directly to the reduced section of the specimen.When neces-sary,other arrangements (discussed in 9.6.3)may be used by prior agreement of the parties concerned.For example,special arrangements may be necessary in testing brittle materials where failure is apt to be initiated at an extensometer knife edge.5.4.4To attach the extensometer to miniature specimens may be impractical.In this case,separation of the specimen holders or crossheads may be recorded and used to determine strains corresponding to the 0.2%offset yield strength.The value so obtained is of inferior accuracy and must be clearlymarked as “approximate yield strength.”The observed exten-sion should be adjusted by the procedure described in 9.6.3and 10.1.3.5.4.5The extensometer system should include a means of indicating strain rate.N OTE 5—The strain rate limits listed in 9.6are difficult to maintain manually by using equipment which has a pacer disk and a follower hand.Equipment that makes timing marks on the edge of the force-strain record requires some trial and error to set the machine controls to give the specified rate during yielding.Such marks are,however,very useful in determining the strain rate after test.Convenient pacers,recently offered by several manufacturers,work on the principle of an indicating tachom-eter.The machine is manually adjusted to keep the indicator hand of the pacer stationary at a predetermined number.5.5Room-Temperature Control —Unless the extensometer is known to be insensitive to ambient temperature changes,the range of ambient temperature should not exceed 6°C (10°F)while the extensometer is attached.The testing machine should not be exposed to perceptibly varying drafts.6.Sampling 6.1Unlessotherwise specified the following sampling pro-cedures shall be followed:6.1.1Samples of the material to provide test specimens shall be taken from such locations as to be representative of the lot from which it was taken.6.1.2Samples shall be taken from material in the final condition (temper).One test shall be made on each lot.6.1.3A lot shall consist of all material from the same heat,nominal size,and condition (temper).7.Test Specimens and Sample 7.1The size and shape of the test specimens should be based primarily on the requirements necessary to obtain representative samples of the material being investigated.7.2Unless otherwise specified,test specimens shall be oriented such that the axis of the specimen is parallel to the direction of fabrication,and located as follows:7.2.1At the center for products 38mm (11⁄2in.)or less in thickness,diameter,or distance between flats.7.2.2Midway from the center to the surface for products over 38mm (11⁄2in.)in thickness,diameter,or distance between flats.7.3Specimen configurations described in Test Methods E 8,are generally suitable for tests at elevated temperatures;how-ever,tighter dimensional tolerances are recommended in 7.6.The particular specimen used should be mainly governed by the requirements specified in 7.1.When the dimensions of the material permit,except for sheet and strip,the gage length of the specimens should have a circular cross section.The largest diameter specimen consistent with that described in 7.1should be used,except that the diameter need not be greater than 12.7mm (0.500in.).The ratio of gage length to diameter should be 4,as for the standard specimens described in Test Methods E 8.If different ratios are used,the specifics should be reported in the results.N OTE 6—Specimen size in itself has little effect on tensile properties provided the material is not subject to appreciable surface corrosion,lack of soundness,or orientation effects.A small number of grains in the4Tishler,D.N.,and Wells,C.H.,“An Improved High-Temperature Extensom-eter,”Materials Research and Standards ,American Society for Testing and Materials,MTRSA,V ol 6,No.1,January 1966,pp.20–22.取样试验试样和样品specimen cross section,or preferred orientation of grains due to fabrica-tion conditions,can have a pronounced effect on the test results.When corrosion is a factor in testing,the results do become a function of specimen size.Likewise,surface preparation of specimens,if affecting results,becomes more important as the specimen size is reduced.7.4Specimens of circular cross section should have threaded,shouldered,or other suitable ends for gripping which will meet the requirements of 5.1.2.N OTE 7—Satisfactory axial alignment may be obtained with precisely machined threaded ends.But at temperatures where oxidation and creep are readily apparent,precisely fitted threads are difficult to maintain and to separate after test.Practical considerations require the use of relatively loose-fitting threads.Other gripping methods have been successfully used.5,67.5For rectangular specimens some modifications of the standard specimens described in Test Methods E 8are usually necessary to permit application of the force to the specimen in the furnace with the axiality specified in 5.1.2.If the material available is sufficient,the use of elongated shoulder ends to permit gripping outside the furnace is the easiest method.When the length of the specimen is necessarily restricted,several methods of gripping may be used as follows:7.5.1A device that applies the force through a cylindrical pin in each of the enlarged ends of the specimen.The pin holes should be accurately centered on extensions of the centerline of the gage section.Grips of this type can provide good axiality of loading.57.5.2High-temperature sheet grips similar to those illus-trated in Test Methods E 8and described as self-adjusting grips.These have proven satisfactory for testing sheet materi-als that cannot be tested satisfactorily in the usual type of wedge grips.7.5.3Extension tabs may be welded or brazed to the specimen shoulders and extended to grips outside the furnace.When these are used,care must be exercised to maintain coaxiality of the centerlines of the extensions and the gage length.Any brazing or welding should be done in a jig or fixture to maintain accurate alignment of the parts.Any machining should be done after brazing or welding.7.5.4Grips that conform to and apply force against the fillets at the ends of the reduced section.7.6The diameter (or width)at the ends of the reduced section of the specimen should not be less than the diameter (or width)at the center of the reduced section.It may be desirable to have the diameter (or width)of the reduced section of the specimen slightly smaller at the center than at the ends.This difference should not exceed 0.5%of the diameter (or width).When specimens of this form are used to test brittle materials,failure may regularly occur at the fillets.In these cases,the center of the reduced section may be made smaller by a gradual taper from the ends and the exception to the requirements above noted in the report.Specimen surfaces shall be smooth and free from undercuts and scratches.Cold work introduced through machining or handling can produce high residual stresses or other undesired effects and should be minimized.The axis of the reduced section should be straight within 60.5%of the diameter.Threads of the specimen should be concentric with this axis within the same tolerance.Other means of gripping should have comparable tolerances.7.7For cast-to-size specimens it may not be possible to adhere to the diameter,straightness,and concentricity limita-tions of 7.6,but every effort should be made to approach these as closely as possible.If the specimen does not meet the requirements specified in 7.6,the test report should so state.The magnitude of the deviations should be reported.8.Calibration and Standardization 8.1The following devicesshould be calibrated against standards traced to the National Institute of Standards and Technology.Applicable ASTM methods are listed beside the device.Force-measuring system E 4and E 74Extensometer E 83Thermocouples A E 220Potentiometers MicrometersAMelting point methods are also recommended for thermocouple calibration.8.1.1Axiality of the loading apparatus should be measured as described in 5.1.2.8.2Calibrations should be as frequent as is necessary to assure that the errors in all tests do not exceed the permissible variations listed in this test method.The maximum period between calibrations of the testing machine shall be one year.Instruments in either constant or nearly constant use should be calibrated more frequently;those used only occasionally should be calibrated before each use.9.Procedure 9.1Measurement of Cross-Sectional Area —Determine the minimum cross-sectional area of the reduced section of the specimen as specified in 7.2of Test Methods E 8or E 8M.In addition measure the largest diameter (or width)in the reduced section and compare with the minimum value to determine whether the requirements of 7.6are satisfied.9.2Measurement of Original Length :9.2.1Unless otherwise specified,base all values for elon-gation on a gage length equal to four diameters in the case of round specimens and four times the width in the case of rectangular specimens,the gage length being punched or scribed on the reduced section of the specimen.N OTE 8—Elongation values of specimens with rectangular cross sec-tions cannot be compared unless all dimensions including the thickness are equal.Therefore,an elongation specification should include the specimen cross-sectional dimensions as well as the gage ing a gage length equal to 4.5times the square root of the cross-sectional area5Schmieder,A.K.,“Measuring the Apparatus Contributions to Bending in Tension Specimens,”Elevated Temperature Testing Problem Areas,ASTM STP 488,American Society for Testing and Materials,1971,pp.15–42.6Penny,R.K.,Ellison,E.G.,and Webster,G.A.,“Specimen Alignment and Strain Measurement in Axial Creep Tests,”Materials Research and Standards ,American Society for Testing and Materials,MTRSA,V ol 6,No.2,February 1966,pp.76–84.校准和标准化步骤compensates somewhat for variations in specimen thickness but even this does not result in the same value of elongation when specimens of the same material are machined to different thicknesses and tested.79.2.2When testing metals of limited ductility gage marks punched or scribed on the reduced section may be undesirable because fracture may occur at the stress concentrations so caused.Then,place gage marks on the shoulders or measure the over-all length of the specimen.Also measure the adjusted length of the reduced section to the nearest 0.2mm (0.01in.)as described in 9.2.3.If a gage length,other than that specified in 9.2.1is employed to measure elongation,describe the gage length in the report.In the case of acceptance tests,any deviation from 9.2.1must be agreed upon before testing.N OTE 9—The availability of flexible ceramic fiber cords for mounting of high temperature extensometers with high purity ceramic rods with chisel or vee-chisel ends,provides a good measure of ductility without excessive damage to the gage section caused by other types of extensom-eters or traditional punch or scribe marks.Damage to the rods from specimen failure may be minimized through the use of spring loaded attachment fixtures.Non contact extensometers may also be used for this purpose.9.2.3When the extensometer is to be attached to the specimen shoulders,measure the adjusted length of the re-duced section between points on the two fillets where the diameter (or width)is 1.05times the diameter (or width)of the reduced section.The strain rate and offset yield calculations are based on this dimension (see 9.6.3,10.1.2,and 10.3).N OTE 10—In the yield region,stress is approximately proportional to offset strain to a power which usually lies in the range from zero to 0.20.For specimens of circular cross section the above value of adjusted length of the reduced section was found by calculation to give an error in yield stress of less than 1⁄2%within this range of exponents and for fillet radii ranging from 1⁄2to 1times the diameter of the reduced section.The method of calculation was similar to that used by Thomas and Carlson.89.3Cleaning Specimen —Wash carefully the reduced sec-tion and those parts of the specimen which contact the grips in clean alcohol,acetone,or other suitable solvent that will not affect the metal being tested.9.4Temperature Control :9.4.1Form the thermocouple bead in accordance with Guide E 633.9.4.2In attaching thermocouples to a specimen,the junction must be kept in intimate contact with the specimen and shielded from radiation.Shielding may be omitted if,for a particular furnace and test temperature,the difference in indicated temperature from an unshielded bead and a bead inserted in a hole in the specimen has been shown to be less than one half the variation listed in 9.4.4.The bead should be as small as possible and there should be no shorting of the circuit (such as could occur from twisted wires behind the bead).Ceramic insulators should be used on the thermocouples in the hot zone.If some other electrical insulation material isused in the hot zone,it should be determined that the electrical insulating properties are maintained at higher temperatures.9.4.3When the length of the reduced section is less than 50mm (2in.),attach at least two thermocouples to the specimen,one near each end of the reduced section.For reduced sections greater-than or equal to 50mm (2in.)add a third thermocouple near the center of the reduced section.9.4.4For the duration of the test,(defined as the time from the application of force until fracture),do not permit the difference between the indicated temperature and the nominal test temperature to exceed the following limits:Up to and including 1000°C (1800°F)63°C (5°F)Above 1000°C (1800°F)66°C (10°F)When testing at temperatures of a few hundred degrees,internal heating due to plastic working may raise the tempera-ture of the specimen above the limits specified.In these cases include the temperature at maximum force and the reason for the overshoot in the report.9.4.5The term “indicated temperature”means the tempera-ture that is indicated by the temperature measuring device using good quality pyrometric practice.N OTE 11—It is recognized that true temperature may vary more than the indicated temperature.The permissible indicated temperature variations in 9.4.4are not to be construed as minimizing the importance of good pyrometric practice and precise temperature control.All laboratories should keep both indicated and true temperature variations as small as practicable.It is well recognized,in view of the extreme dependency of strength of materials on temperature,that close temperature control is necessary.The limits prescribed represent ranges which are common practice.9.4.6Temperature overshoots during heating shall not ex-ceed the above limits,unless agreed upon by the customer and the supplier.The heating characteristics of the furnace and the temperature control system should be studied to determine the power input,temperature set point,proportioning control adjustment,and control-thermocouple placement necessary to limit transient temperature overshoots.It may be desirable to stabilize the furnace at a temperature from 6to 28°C below the nominal test temperature before making the final adjustments.If allowed,overshoots shall be reported,with details of magnitude and duration.9.4.7The time of holding at temperature prior to the start of the test should be governed by the time necessary to ensure that the specimen has reached equilibrium and that the temperature can be maintained within the limits specified in 9.4.4.Unless otherwise specified this time should not be less than 20minutes.Report the time to attain test temperature and the time at temperature before testing.9.5Connecting Specimen to the Machine —Take care not to introduce nonaxial forces while installing the specimen.For example,threaded connections should not be turned to the end of the threads or “bottomed.”If threads are loosely fitted,lightly apply force to the specimen string and manually move it in the transverse direction until the force drops to its minimum value before testing.If packing is used to seal the furnace,it must not be so tight that the extensometer arms or pull rods are displaced or their movement restricted.9.6Strain Measurement and Strain Rate :7Stickley,G.W.,and Brownhill,D.J.,“Elongation and Yield Strength of Aluminum Alloys as Related to Gage Length and Offset,”Proceedings ,American Society for Testing and Materials,ASTEA,V ol 65,1965,pp 597–616.8Thomas,J.M.,and Carlson,J.F.,“Errors in Deformation Measurements for Elevated Temperature Tension Tests,”ASTM Bulletin ,ASTM,May 1955,pp.47–51.。
管子高温拉伸实验报告(3篇)
第1篇一、实验目的1. 了解管子高温拉伸实验的基本原理和方法。
2. 测定不同温度下管材的力学性能，包括抗拉强度、屈服强度、延伸率等。
3. 分析温度对管材力学性能的影响，探讨高温对管材性能的影响机制。
4. 掌握高温拉伸实验的操作技巧和数据处理方法。
二、实验原理管子高温拉伸实验是一种常用的材料力学性能测试方法。
通过在高温条件下对管材进行拉伸，可以测定管材在高温状态下的力学性能，为管材的设计、加工和应用提供依据。
实验过程中，主要关注以下参数：1. 抗拉强度：管材在拉伸过程中所能承受的最大应力。
2. 屈服强度：管材在拉伸过程中开始发生塑性变形时的应力。
3. 延伸率：管材在拉伸过程中长度增加的百分比。
4. 断裂伸长率：管材断裂前长度增加的百分比。
三、实验设备与材料1. 实验设备：高温拉伸试验机、高温炉、温度控制器、引伸计、万能力学试验机、游标卡尺等。
2. 实验材料：不锈钢管、碳钢管等。
四、实验步骤1. 准备实验材料：根据实验要求，选取合适规格的管材，切割成所需长度和直径的试样。
2. 预热：将试样放入高温炉中，加热至预定温度，保持一定时间，使试样达到热平衡状态。
3. 测试：将试样安装在高温拉伸试验机上，调整试验机参数，进行拉伸实验。
在拉伸过程中，实时记录拉伸力、位移、温度等数据。
4. 数据处理：根据实验数据，计算抗拉强度、屈服强度、延伸率等力学性能指标。
五、实验结果与分析1. 实验数据：| 温度（℃） | 抗拉强度（MPa） | 屈服强度（MPa） | 延伸率（%） || ---------- | ---------------- | ---------------- | ------------ || 300 | 600 | 450 | 20 || 400 | 550 | 400 | 15 || 500 | 500 | 350 | 10 || 600 | 450 | 300 | 5 |2. 分析：从实验数据可以看出，随着温度的升高，管材的抗拉强度、屈服强度和延伸率均呈下降趋势。
《拉伸测E实验》课件
进行拉伸实验并记录数据
开始拉伸实验，逐渐增加拉伸机的拉伸 力，使试样逐渐被拉伸。
在实验过程中，观察并记录引伸计的读 记录实验过程中的异常现象，如试样断
数，记录试样的变化情况。
裂、变形等。
结束实验并整理器材
当实验结束时，停止拉伸机的拉伸力，并释放试样。 关闭引伸计，并将实验数据导出或记录在实验报告中。
整理实验器材，清洁并归位，以便下次使用。
05
实验结果分析
数据处理与计算
数据清洗
在实验过程中，可能会产生一些异常数据，需要进行数据清 洗，排除异常值和离群点，确保数据的有效性和准确性。
数据转换
为了便于分析和处理，有时需要对数据进行转换，例如将厘 米转换为米，或者将数据转换为对数或指数形式。
弹性模量的值及其误差分析
根据试样的形状和尺寸，选择 合适的夹具将试样夹紧在拉伸 机上。
确保夹具安装牢固，不会在实 验过程中松动或滑落。
调整拉伸机的初始位置，确保 试样的初始状态良好。
调整引伸计并记录初始数据
调整引伸计的位置，使其与试样 表面接触，并保持平行。
启动引伸计，记录试样的初始长 度、直径等数据。
确保引伸计的读数准确无误，没 有误差。
弹性模量的计算公式
01
弹性模量E的计算公式：E = σ / ε
02
其中，σ为应力，ε为应变。通过 实验测得应力应变数据，代入公 式即可计算出材料的弹性模量。
03
实验器材
拉伸机
用于对试样施加拉伸 力，使试样产生拉伸 变形。
拉伸机的精度和稳定 性对实验结果有很大 影响。
一般由动力系统、传 动系统和控制系统组 成，可调节拉伸速度 和力值。
实验步骤
准备实验器材、安装试样、拉 伸试样、记录数据、计算弹性 模量。
高温拉伸试验标准
高温拉伸试验标准
高温拉伸试验是一种材料性能测试，旨在了解材料在高温下拉伸
时表现出来的强度和弹性，通常以普通温度下试验结果为基础，来模
拟材料在特定高温作用下的形变反应。
根据《GB/T16491-1996金属材
料热处理综合试验方法》中规定，高温拉伸试验应满足以下要求： 1、材料取样：根据试验材料的性能要求，从工件中取出一定数量的测试
样品，清理表面脏物，表面处理等等； 2、试验温度： zui高可达材
料的A点（脆性点）或其他温度； 3、试验速度：冷加速度为
50mm/min至500mm/min； 4、试验评定标准：根据测定出的高温拉伸
准度和力学性能来评定材料是否符合要求，若不符合，可根据改进要
求对材料进行热处理或锻造等方式改善，以达到想要的性能指标要求。
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试样和样坯
圆形试样 • 横截面试样应带有螺纹、凸台、或符合要求的其他适于夹持的头部 矩形试样 • 一种通过试样每端加粗头部的柱形销来施加负荷的装置，夹头的加 荷轴向性很好 • 自调节夹头对于高温薄板比锲形夹具较为满意 • 伸长调节片可焊接或铜焊于试样凸台上，并将其延伸出炉外夹持 • 与缩减部分末端的过渡圆弧相配合并对过渡圆弧施加负荷的夹头 铸造试样 • 对直径、平直度和同心度规定办不到时，应尽可能接近这些要求 • 如果试样不符合尺寸要求，试验报告应如实注明并报告偏差大小
试验程序
记录最大负荷
•如果使用负荷- 伸长记录仪自动记录，则在引伸计敏感元件卸下之后 应继续记录负荷。在任何情况下，都得观测和人工记录最大负荷。
试验之后试样的测量
•对延伸率的测量，当将断开的试样的两个断口仔细拼接在一起，并 在室温下测量两个标记之间的距离或试样全长，精确到 0.01 英寸 （ 0.2 毫米） •如果断口表面的任何部分超出试样缩减部分中间一半时，所获得的 这个延伸率就不能代表这个材料。 •在验收试验情况下，如果延伸率符合规定的最小值时，则不要求重 做试验 •如果延伸率小于规定的最小值时，则此试验作废，而且要重做试验
试验程序---试样安装
总体要求：要注意安装试样时不引入 非轴向力
螺纹是松配合的， 使用填料密封炉 试验前可稍许加 子，不应封得太 螺纹连接不应施 荷拉紧试样，并 至螺纹尽头或底 紧以致引伸计杆 用手横向摇动试 部 或拉杆受到位移 样，直至负荷降 或运动的阻碍。 到最小值
试验程序--应变测量和应变率
需要测定屈服强度 • 测定屈服强度期间，试样均匀部分的应变率应保持 在 0.005 ± 0.002/ 分范围内 • 测定屈服强度之后，增加十字头移动速率到每分钟 试样缩减部分修正长度的 0.05 ± 0.01 倍。 • 为了避免引伸计受损伤，在达到最大负荷前将引伸 计的敏感元件卸下
不要求测定屈服强度时
标距是标在试样上两标记之间用于测定断后延伸率的原始距离.
轴向应变是在相对两侧并与试样轴等距离处所测量的应变之平均值
最大弯曲应变是在试样的最小截面段上弯曲应变的最大值。它可以从两个不同的纵向位置在每个位置上取三个 圈向位置测得的应变计算得到。
设备要求-----试验机
试验机的精度满足于E4 方法 " 试验机的校验 " 中规定的允许偏差范围内 轴向性要求
≤ 1000 ℃，± 3 ℃
＞可能使温度升 高超过上述规定范围。在这种情况 下，报告中应包括最大负荷时的温 度和过冲的理由。
设备要求-----温度测量装置
试验期间（从加力到断裂的时间），指示温度与标称温度之差不应超过下列限度：≤ 1000 ℃，± 3 ℃ ＞ 1000 ℃，± 6 ℃ 应用与电位计或毫伏计相连接的热电偶进行温度测量 应使用标定过的热电偶测量温度 • 用来制作贱金属热电偶的金属丝的每一批中标定代表性的热电偶 • 除相当低的使用温度外，重新使用贱金属热电偶会带来误差，除非重现最初使用时的深 入深度和温度梯度 • 用代表性热电偶标定贱金属热电偶，而用于测量试样温度的实际热电偶不予标定 • 不应再次使用没有剪去暴露热区部分热电偶丝并重新焊接的贱金属热电偶 • 贱金属热电偶在相当低的温度使用后而再次使用，应证明这种标定不受暴露条件过份影 响的重新标定数据。 • 贵金属热电偶由于污染等容易带来误差，应定期进行退火及复核标定。使用之前，应采 取措施保持热电偶清洁。 • 热电偶在使用期间难于测定标定值的漂移。当试验期间漂移已成为一个问题时，应设法 检查试验期间试样上热电偶的读数。对于使用后可靠的热电偶标定，试验炉子的温度梯 度必定在重新标定时重现。 • 温度测量、控制和记录的仪表应相应为二级标准。应在正常使用的导线位置上检查导线 误差。
试验程序
对圆形横截面试样的断面收缩率测量 • 先将断裂的试样的两个断口仔细拼接在一起，并在室 温下测量其最小直径，精确到 0.2 毫米（ 0.01 英寸） • 如果断裂的横截面不圆，则要进行足够的测量以确定 断裂处横截面积 • 如果断裂是发生在圆角处或标记上，则此断面收缩率 不能代表该材料 • 在验收试验情况下，如果断面收缩率达到规定的最小 值，则不要求重做试验 • 如果断面收缩率低于规定最小值时，则此试验作废， 并且重做试验
对于容易受其环境（例如金属在空气中氧化）浸蚀的材料高温拉伸试验， 可以把试样封闭在容器内，使之能够在真空或惰性气氛中进行试验。
设备要求-----加热装置
除非双方事先特 意商定其他介质， 否则均应用电阻 丝炉或辐射炉在 大气气氛中加热 试样。
试验期间（从加力到断裂的时间）， 指示温度与标称温度之差不应超过 下列限度：
试验程序----温度控制
“指示温度” 指通过使用可靠的高温测量方法时温度测量装置指示的温度。
除非用户和生产厂之间同意，否则在加热期间，温度过冲不应超过上述范围
在最后调节前，在低于标称温度 6~28 ℃ 的温度下稳定炉子是必要的
要详细报告温度过冲大小和过冲持续时间
应根据确保试样温度达到平衡和温度能保持在 9.4.4 条中规定范围内所必须 的时间来控制试验开始前的保温时间。除非另作规定，这一保温时间不应小 于 20 分钟。要报告达到试验温度的时间和加荷前的保温时间。
试验程序
试样横截面积测量
• 测定试样缩减部分的最小横截面积 • 允许缩减部分中间处直径（或宽度）比其两端的直径（或宽度）稍小，但其差不应超 过直径（或宽度）的 0.5%
试样原标距测量
• 除非另有规定，以标准作为所有延伸率的基准，对于圆形试棒，标长为直径的4倍， 对于矩形试棒，标长为宽度的4倍。在试样缩减部分用打点或划线方式标出标距长度 • 对于塑性差的材料，在缩减段的打点或刻划标记，易产生应力集中。那么标记可以标 在试样凸台，或通过测量试样的总长度。测量缩减部分的修正长度，精确到0.01英寸 （0.2毫米） • 当引伸计装卡在试样凸台上时，应测量缩减部分两过渡弧直径（或宽度）为 1.05 倍于 缩减部分的直径（或宽度）处之间的修正长度。应变率和屈服强度的计算，是以这些 尺寸为基础的
当有可能时，应把引伸计直接装卡到试样的缩减部分
将引伸计安装在小试样上可能难以实行。在这种情况下，可记录试样两夹头或十字头的分离移动，并用 此来测定与 0.2% 偏置量屈服强度相应的应变。这样得到数值的精确度较低，因而必须注明为“近似屈服 强度”。观测到的伸长应通过 9.6.3 和 10.1.3 条所叙述的程序进行修正
标定与标准化
需标定和校准的项目 • 力值——测量系统 • 引伸计 • 加荷装置的轴向性 • 热电偶 • 电位计 • 测微计 （千分尺） 标定周期 • 试验机至少应每年标定一次 • 经常使用或差不多经常使用的仪器更应经常进行标定。 • 偶而使用的仪器应在每次使用前进行标定 E4 和 E74 E83
E220
设备要求-----引伸计系统
依据方法ASTM E83 挑选符合要求的引伸计，确定灵敏度和精确度
•为了测定 0.1% 或更大偏置量的屈服强度，可使用 B2 级引伸计 •引伸计与高温炉子一起使用时，应进行检验以确保其精度
当仅在试样一侧测量应变时，在小应变下负荷的不同心度通常足以产生明显误差，因此，应装卡引伸计 到试样相对两侧的应变，则应力——应变曲线的斜度通常将在弹性模量的10%以内。
热电偶绑扎到试样上时，其接点必须与试样保持紧密接触，并要遮蔽直接的热辐射热
当缩减部分的长度<50 毫米时，在两端各固定一支热电偶。≥50 毫米时在缩减部分的 中心附近添加第三个热电偶
试验期间（从加力到断裂的时间），指示温度与名义温度之差不应超过下列限度
•≤ 1000 ℃，± 3 ℃热，可能引起试样温度升高而超出上述规定范围。 在这种情况下，报告中应包括最大负荷时的温度和过冲的理由。
试验程序---计算
屈服强度 •除非另作规定，屈服强度按试验方程E8/E8M中的规定，在残余应变为 0.2%下测定并报告。 •引伸计必须装卡在试样的凸台上，以小截面段的调整长度作为残余变形伸 长量（单位为英寸或毫米）作为基础。即对应残余应变时的屈服强度为小 截面段的调整长度的 0.002 倍 •如果记录夹头或十字头的分离位移，则按下面两步修正观测的伸长 •首先，补偿试验机的弹性应变、夹头的歪扭和凸台的应变，从标准试样值 扣除相应负荷下缩短的试样值 •其次，用修正过缩减段的应变数据，仅报告 0.2% 或更大偏置数的屈服强 度，并标明为“近似屈服强度”。 抗拉强度 • 通过区分试验中试样断裂时的最大截面，除以试样小截面段的原始最小横 截面积来计算得到抗拉强度。
清洗试样
• 用酒精、丙酮或其他合适的对测试金属无害的溶剂仔细清洗试样的缩减部分和夹头相 接触的部分
试验程序----温度控制
按照 E633 焊接热电偶的焊珠，热电偶焊珠应尽可能小，不应有短路（在热电偶焊珠 后面可能发生扭接），在热电偶热区通常使用陶瓷珠绝缘，若用其他材料需要验证在 高温下是否还具有点绝缘性。
• 试样的取向应使试样轴线平行于加工方向 •厚度、直径或两面间的距离等于或小于 38 毫米的产品在中心部位 •厚度、直径或两面间的距离大于 38 毫米的产品，在产品的中心至其表面的中间部位
试样尺寸要求
•试验方法E8/E8M中描述的试样形状通常适用于高温试验 •试样缩减部分两端的直径（或宽度）不得小于缩减部分中间处的直径（或宽度） •允许缩减部分中间处直径（或宽度）比其两端的直径（或宽度）稍小，但其差不应超过 直径（或宽度）的 0.5% ，但脆性材料可能仍会在过渡圆弧处发生断裂引起试验失败。缩减 部分的中间比其两端可以做得小些，从两端到中间带有一个逐渐变小的锥度，而超出上述要 求应在报告中注明 •试样表面应光滑而无切口和划痕 •采取措施把冷加工而产生的高残余应力或其它对表面层的干扰减至最小 •试样缩减部分的轴线应平直，偏差不超过直径的± 0.5%
• 试验机具有合格条件的零负荷和最低负荷下读取的应变读数为基础进行计算时，试验机 和夹头应能对精确加工的试样施加负荷而使试样的最大弯曲应变不超过其轴向应变的 10% 。 • 试验脆性材料时，即使是在 10% 的弯曲应变下也可以产生比在改进的轴向性情况下应该 得到的强度低 • 通过室温下测定的轴向性来证明试验设备合格。在对设备进行轴向性测量时，所用试样 形状应与在高温下所用的试样相同。 • 在高温下重复使用，夹持装置和拉杆可能氧化、翘曲和蠕变，结果可能增加弯屈应力。 因此，应定期重复检验夹头和拉杆的轴向性，必要时应重新加工。