材料导论习题(英文版)

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材料导论 (35)

Video 5: Amorphous or Crystalline State of PolymersNow, let’s talk about the solid state of polymers.Structurally, materials in solid state may be amorphous or crystalline.We all know that substances having small molecules (such as water, CO2 and methane) are normally totally crystalline as solids, or totally amorphous as liquids.In contrast, polymers are macro-molecules with high-molecular weight, and may have a wide molecular weight distribution. Therefore, the concept of crystallinity in polymers must be different from that in low-molecular-weight substances.今天讲固态聚合物形态。

从结构上讲，固态材料可呈无定形和结晶两种形态。

固态小分子物质如水、二氧化碳和甲烷通常可呈完全结晶形态，而液相则是完全无定形的。

相比而言，聚合物分子量很高，且具有一定分子量分布。

因此，聚合物的结晶与小分子物质的结晶不同。

When polymers are cooled from the molten state or concentrated from a dilute solution, their chains could be randomly twisted, coiled and entangled. This twisting, coiling prevents the strict ordering of polymer chains, resulting in a disorder arrangement of polymer chains, only a short-range order of repeating units. Consequently, we can only get an amorphous solid. This is a common situation for polymers in solid state. Possibly, individual polymer chains are folded (back and forth) on themselves and packed in a regular manner or in an orderly fashion. This will form a three-dimensional long-range ordered arrangement, that is, a crystalline structure of polymer.熔融态聚合物冷却时，或聚合物稀溶液浓缩时，分子链会随机蜷缩、缠绕。

材料导论 (56)

In the previous lectures, we have already know that degradation is a vital properites of biomaterials. Biodegradable polymers normally possess labile functional groups accessible to biological or non-biological mechanisms of degradation. Biodegradable polymeric biomaterials will gradually degrade into water soluble oligomers and monomers that eliminate from a human body after fulfilling their intended use. The use of biodegradable synthetic polymers as biomaterials is also due to that their mechanical and physical properties can readily be adjusted by varying preparation techniques and molecular structure. Therefore, biodegradable polymeric biomaterials are intensively studied and used in biomedical and tissue engineering applications.在之前的课程中，我们已经知道降解是生物材料的一个重要特性。

生物可降解聚合物通常具有生物可降解或非生物可降解机制的不稳定官能团。

生物降解聚合物生物材料将逐渐降解为水溶性低聚物和单体，在完成预期的用途后可以从人体中去除。

材料导论中英文讲稿 (4)

6.2.2 Porosity and DensityHello, everybody, in this Section, we are going to talk about porosity and density.译文：在这一节，我们将讨论气孔率和密度。

When referring to a solid material such as a part made from copper or stainless steel, the word density takes into consideration the microstructures that contains no porosity. By which term we do not mean the voids or vacancies in the atomic structure. In speaking of a solid material we mean the material’s theoretical density or mass density, it is the mass of a material divided by its volume.我们通常说到密度，指的是理论密度，表示结构中不包含气孔。

通过质量除以体积得到。

译文：当提到一种固体材料，尤其是由铜或不锈钢制成的材料时，密度这个词通常会考虑到一个没有气孔率的微观结构，在这个词中，我们指的不是原子结构中的孔洞或空位。

我们通常说到密度，指的是理论密度，表示结构中不包含气孔。

通过质量除以体积得到。

There are two factors influence the density of material. Atomic weight is a major factor in determining the density of the materials. Low-atomic-weight elements have low densities. 影响材料密度的因素有两个。

材料科学与工程导论(双语)复习用.docx

材料科学与工程导论1 Polymerization (聚合作用)is the process by which small molecules (分子) consisting of one unit or a few units are chemically joined to create these giant molecules. Those small molecule units are called _____A) polymers B) monomers (单体) C) oligomers D)elastomerscable.A)For automobile bumper, the best choice of polymer is Natural Rubber.B)For mineral water bottle, the best choice of polymer is Low-Density (密度) Polyethylene (聚乙烯)C)For insulating cable, the best choice of polymer is polystyrene (聚苯乙烯).D)For mineral water bottle^ the best choice of polymer is Polyethylene Terephthalate.3)In general, for a given type of thermoplastic (热塑性塑胶)the tensile (可延展的) strength, creep resistance impact toughness, wear resistance, and melting temperature all increase with _______A) degree of polymerization B)density of branching C)tacticity D) crystallinity4)ABS, composed of acrylonitrile, butadiene, and styrene (苯乙烯)，is one of the most common polymer materials. Styrene and acrylonitrile form a liner copolymer (异量分子聚合物)(SNA) that serves as a matrix. Styrene and butadiene also form a liner copolymer, BS rubber, which acts as the __________ material.D or B?A)fire retardant B) filler C) cross-linking D)plasticizer5)Epoxies (环氧树月旨)are thermosetting polymers formed from molecules containinga tight C-O-C ring. During polymerization, the C-O-C rings are opened and the bonds are rearranged to join the molecules. If epoxy is used as an adhesive (粘齐ll) for a variety of applications, which kind of adhesives does it belong to?A)Chemically Reactive AdhesivesB)Evaporation or Diffusion AdhesivesC)Hot-Melt Adhesives D) Pressure-Sensitive Adhesives6)What area the major advantages associated with plastic compared to ceramics(陶瓷)，glasses, and metallic materials?A)lightweight and corrosion(铁锈,腐蚀卜resistantB)high strength and high-temperature resistantC)high-temperature resistant and insulatingD)high stiffness and corrosion-resistant7)Which one is not a thermoset polymer?A) Polyethylene B) Natural Rubber C) Epoxy D) Phenolic8)Depending on the degree of cross-linking, the polyurethanes behave as thermosetting polymers, thermoplastics (热塑性塑胶)，or elastomers. These polymers find application as fibers, coatings, and foams for furniture, mattress, and insulation. Why polyurethanes are versatile(为什么聚氨酯是通用的)？A) for their polar repeat unit B) for their linear structureC) for their multi-functional monomer D) for their tactictity structure9) Liquid Crystalline(透明的)Polymers are polymers which behave as _____A) liquid B) thermoplastic C) thernoset D) oriented (取向)rods10) The glass temperature (Tg) is typically about ______ t imes the absolute melting temperature (Tm).A) 0.2 to 0.3 B) 0.5 to 0.7 C) 0.8 to 1.0 D) 1.0 to 2.011) Most thermoplastic exhibit a non-Newtonian and visicoelastic behavio 匸 The stressand train are not linearly related for most parts of the stress-strain curve. The viscoelastic behavior means when an external (夕卜部的)force is applied to a B) both elastic and plastic (塑性) C) only plastic D) neither elastic nor plastic12) Compare the tensile strength of LDPE, HDPE, PVE, PP, and arrange them in sequence (顺序)from high strength to low tensile strength•A) LOPE>HDPE>PVE>PP B) LDPE>HDPE>PP>PVCC) PVC>PP>HDPE>LDPE D) PVC>HDPE>PP>LDPE13) Degree of polymerization is usually used to characterize _______A) cross-linking network B) thermosetting polymerC) polymer degradation D) thermoplastic polymer14) Silicones (硅)are important elastomer based on chains composed of silicon and oxygen atoms. The silicone rubbers provide high-temperature resistance, permitting use of the elastomer at temperature as high as ____________ °C. Low molecular weight silicones form liquids and are known as silicon oils.A) 100 B) 150 C) 200 D) 30015) There are a lot of thermoplastic processing methods, typical forming processincludes: extrusion, blow molding, injection molding, thermoforming, calendaring and spinning ・ If we want to produce sping water bottles, which processing way is best choice?A) extrusion 挤ill 成型 B) blow molding 吹塑成型 C) injection molding 注射成型D) thermoforming 热成型16) The recycling of thermoplastics is relatively easy and practiced widely. Many of the everyday plastic products you encounter (bags, soda bottles, yogurt containers, etc.) have numbers stamped on them. For PRT products, the number is 1. For HOPE and LDPE, the numbers are __________ ，respectively. Other plastics are marked number 7,A) 3 and 4 B) 4 and 5 C) 2 and 4 D) 2 and 317) The temperature above which a polymer burns, chars, or decompose. Which team is appropriately used in describing the remperature ・A) Tg B)Td C) Tm D) HDT18) Which forming process is not a best choice for thermosetting polymers.A) Compression molding B)transfer moldingC) reaction injection D) spinning19) Elastomers are thermoplastics or lightly cross-linked thermosets that exhibitthermoplastic _ A) only elasticdeformation occurs.greater than ______ elastic deformation.A) 0.2% B)2% C) 20% D)200°/o20)Thermoplastic elastomers combine feature of both thermoplastics and elastomers. At high temperature, these polymers behave as __________ and are plastically into shapes, at how temperature, they behave as ________A) thermoplastics; elastomers B) thermoplastics; thermosetting polymersC) elastomers; thermoplastic D) elastomers; thermosetting polymers21 Define (a) a thermoplastic, (b) thermosetting plastics, (c) elastomers, and (d) thermoplastic elastomers.Thermoplastics :热后可塑性物质是由一些单体聚合成长链组成，它们代表性的特性是可塑性，延展性。

材料导论中英文讲稿 (20)

Module 2 Point Defects and Crystal ImpuritesThe crystal lattices we have described so far are idealized, simplified lattices. However, solids are never perfect in their microstructure, such an idealized solid does not exist. Crystalline solids all contain large numbers of various defects or imperfections, ranging from variable amounts of impurities to missing or misplaced atoms or ions. What is a crystalline defect? A crystalline defect refers to anything that disrupts the regular crystalline structure of the solid.译文：我们之前讨论过的晶格点阵都是理想化的、简化的点阵。

然而固体的微观结构从不完美，那种完美的固体并不存在。

晶体总是存在大量的、各种各样的缺陷，包括不同含量的杂质，缺失或错位的原子或离子。

什么是晶体缺陷？晶体缺陷是指任何破坏固体晶体结构规则排布的区域。

Many of the materials’ properties are profoundly sensitive to crystal defects; the influence is not always in a bad way. Some imperfections can improve certain properties; others may degrade some properties.Just like Prof. Sir Colin Humphreys, University of Cambridge, said: “Crystals are like people, it is the defects in them which tend to make them interesting!” Defects, even in very small concentrations, can have a dramatic impact on the properties of a material. Defects bring about the Development of Semiconductor industry, Production of High-carbon steel, Toughness Reduction of Ceramics, etc.译文：材料的许多性能都对晶体的缺陷非常敏感，但是这种影响并不总是负面的。

材料导论

1. What is the maximum number of electrons that an M shell may contain?A.18B.32C.82. The nucleus of an atom containsProtonsElectronsNeutronsAll of the aboveBoth A and CHow many atoms or molecules are there in a mole of a substance?6.023E234. What type(s) of electron subshell(s) does an L shell contain?a p f ss and fs and pMatch the electron structure below with the element type it represents.1s22s22p63s23p63d104s1Inert gasHalogenAlkali metalAlkaline earth metalTransition metal6.What is the predominant type of bonding for titanium (Ti)?IonicHydrogenCovalentvan der WaalsMetalli7.Of those elements in the list situated below the periodic table, select the one that is one electron short of having its outer shell of electrons completely filled.INSSrAr c8.Which of the following materials may form crystalline solids?PolymersMetalsCeramicsAll of the above9.Which of the following are the most common coordination numbers for ceramic materials?23 and 64 and 124，6 and 810.Which crystal system(s) listed below has (have) the following relationship for the unit cell edge lengths? a = b ≠ cCubicHexagonalTriclinicMonoclinicRhombohedraOrthorhombicTetragonalBoth C and E11.Which crystal system(s) listed below has (have) the following interaxial angle relationship? α = β = γ = 90°CubicHexagonalTriclinicMonoclinicRhombohedralOrthorhombicBoth A and D12.把a、b、c、d四块金属片浸入稀硫酸中，用导线两两相连组成原电池。

材料导论 (31)

Video 1:What is a polymer ?Today I will introduce what a polymer is.Polymers are everywhere. They are all around us in everyday use.You can easily find them in your surroundings, no matter they are natural or synthetic.For example, the rubber used in tire of car, the plastic used in bottles, eyeglasses and cell phone cases.今天给大家介绍-聚合物这一概念。

聚合物无处不在，我们周围聚合物随处可见。

聚合物可以是天然的，也可以是合成的。

例如：汽车轮胎上用的橡胶，制备饮料瓶、眼镜和手机壳用的塑料等，都是聚合物。

You may know the widely used plastics are polyethylene, Polypropylene, and Polystyrene. Every day, you wear a shirt, jacket or coat.Your clothes are made from fibers, maybe a type of natural fiber, such as silk or cotton fiber, maybe a kind of synthetic fiber, usually a Viscose fiber or Rayon, or polyester fiber.You can check the tags attached in your clothes and find the main ingredients of the fiber for your clothes.We can say that our life is based on polymers.关于聚合物，你肯定知道广泛应用的塑料：聚乙烯, 聚丙烯和聚苯乙烯。

材料导论 (3)

Module 2 Secondary BondsBesides primary bonding, another type of bonding is secondary bonding.Secondary bonding is a physical bonding between atoms and molecules,it is relatively weak, about 4-30 kJ/mol. Secondary bonding can be classified into van der Waals forces and hydrogen bonding.Van der Waals forces are the Interactions of atomic or molecular dipoles. Van der Waals forces exist in molecules such as Covalently bonded molecules, like H2, O2, Hydrochloric acid (HCl); and Inert Gases like Argon (Ar) and Xenon (Xe).译文：除了主价键，另外一种键型是次价键。

次价键是一种原子或分子间的物理键，相对较弱，大于4-30 kJ/mol。

次价键可分为范德华力和氢键。

有缘学习更多驾卫星ｙｇｄ３０７６范德华力是原子或者分子偶极间的相互作用力，范德华力存在于像氢气、氧气、盐酸、惰性气体（氩气、氙气）这些共价键分子之间。

范德华力受到分子量和分子极性影响。

分子量大、极性强的分子，分子间范德华力也就大。

Van der Waals forces can be affected by molecular weight and polarity of molecules. High molecular weight, and high polarity of molecules will lead to higher van der Waals forces.According to whether molecules possess a permanent electric dipole moment, molecules can be classified into nonpolar molecules and polar molecules. When centers of positive charge and negative charge coincide, it is called a Nonpolar molecule, such as H2, O2, N2When both the positive and negative charges are localized within the molecule, that means charges are polarized, we call it polar molecules, like Hydrochloric acid (HCl)、Hydrofluoric acid (HF)、Carbon monoxide (CO )…译文：根据是否产生永久的电偶极矩，分子分为非极性分子和极性分子。

材料科学导论英文阅读

Chapter 1 An Overview第一章概述1.1 Introduction1.1介绍Materials are the matter of the universe. These substances have properties that make them useful in structures, machines, devices, products, and systems. The term properties describe behavior of materials when subjected to some external force or condition. For example, the tensile strength of a metal is a measure of the material's resistance to a pulling force. The Family of Materials consists of four main groups of materials: Metals (e.g., steel), Polymers (e.g., plastics), Ceramics (e.g., porcelain), and Composites (e.g., glass-reinforced plastics). The materials in each group have similar properties and/or structures, as will be described later.材料是宇宙的物质。

这些物质的特性使其有用的结构、机器设备、产品和系统。

这个术语属性描述材料的行为时,受到一些外部力量或状态。

例如,抗拉强度的金属是测量的材料抵抗了拉力。

这个家庭的材料由四个主要群体的材料:金属(如钢)、高分子材料(例如:塑料)、陶瓷(如瓷),复合材料(例如,增强塑料)。

材料导论习题(英文版)

1) …… toughness, wear resistance, and melting temperature all increase with ________.A) Degree of polymerizationB) Density of branchingC) TacticityD) Crystallinity2) Choose the type of polymer material you might select for the following applications: an automobile bumper, a mineral water bottle, and an insulation cable.A) For automobile bumper, the best choice of polymer is Natural Rubber.B) For mineral water bottle, the best choice of polymer is Low-Density Polyethylene.C) For insulation cable, the best choice of polymer is Polystyrene.D) For mineral water bottle, the best choice of polymer is Polyethylene Terephthalate.3) Polymerization is the process by which small molecules consisting of one unit or a few unitsare chemically joined to create these giant molecules. Those small molecule units are called _______.A) PolymersB) MonomersC) OligomersD) Elastomers4) Epoxies are thermosetting polymers formed from molecules containing a tight C-O-C ring.During polymerization, the C-O-C rings are opened and the bonds are rearranged to join the molecules. If epoxy is used as an adhesive for a variety of applications, which kind of adhesives does it belong to?A) Chemically Reactive AdhesivesB) Evaporation or Diffusion AdhesivesC) Hot-Melt AdhesivesD) Pressure-Sensitive Adhesives5) Which one is not a thermosetpolymer?A) PolyethyleneB) Natural RubberC) EpoxyD) Phenolic6) Most thermoplastics exhibit a non-Newtonian and viscoelastic behavior. The stress and strainare not linearly related for most parts of the stress-strain curve. The viscoelastic behavior means when an external force applied to a thermoplastic, ________.A) Only elasticB) Both elastic and plasticC) Only plasticD) Neither elastic nor plastic7) Compare the tensile strength of LDPE, HDPE, PVC, PP, and arrange them in sequence fromhigh strength to low tensile strength.A) LDPE>HDPE>PVC>PPB) LDPE>HDPE>PP>PVCC) PVC>PP>HDPE>LDPED) PVC>HDPE>PP>LDPE8) There are a lot of thermoplastic processing methods; typical forming processes includeextrusion, blow molding, injection molding, calendaring, and spinning. If we want to produce spring water bottles, which processing way is best choice？A) ExtrusionB) Blow moldingC) Injection moldingD) Thermoforming9) The recycling of thermoplastics is relatively easy and practiced widely. Many of the everydayplastic products you encounter (bags, soda bottles, yogurt containers, etc.) have numbers stamped on them. For PET products, the number is 1. For HDPE and LDPE, the numbers are ________, respectively. Other plastic are marked number 7.A) 3 and 4B) 4 and 5C) 2 and 4D) 2 and 310) The temperature above which a polymer burns, chars, or decomposes. Which term isappropriately used in describing the temperature?A) T gB) T dC) T mD) HDT11) If a unit cell has axes a=b=c and all angle between axes equal 90°, which crystal system itbelong to?A) CubicB) TetragonalC) OrthorhombicD) Hexagonal12) If a unit cell has axes a≠b≠c and all angles between axes equal 90°, the volume of the unitcell is ________A) a3B) a2cC) abcD) 0.866a2c。

材料导论中英文讲稿 (39)

Module 4 (Metallic Materials金属材料)Video7 Corroison of metals and its prevention金属的腐蚀与防护Hello everyone! Today, let’s talk about corrosion of metals and its prevention.译文：大家好！今天，我们来谈谈金属的腐蚀和防护。

Without any protection, most metals will oxidize (or corrode). Metallic corrosion causes serious economical loss. The newest data show that, the estimated cost of corrosion in China is about 3.34% of GDP every year.译文：在没有任何保护的状态下，多数金属会发生氧化（或者腐蚀）。

金属腐蚀可造成严重的经济损失。

最新的数据显示，中国每年由于腐蚀造成的经济损失估计约占GDP的3.34%。

Corrosion is a natural process, which converts a refined metal to a more chemically stable form, such as its oxide, hydroxide, or sulfide. It is the gradual destruction of metals by chemical or electrochemical reaction with their environment. Remove the environment, and corrosion will stop. Corrosion engineering is the field dedicated to controlling and stopping corrosion.译文：腐蚀是一个自然的过程，它使经过冶炼后得到的金属转变为更具化学稳定性的形式，比如金属的氧化物、氢氧化物或者硫化物。

材料导论 (10)

Module 2 Area DefectsThe third type of defects is called area defects. Area defects are two-dimension defects, and they are boundaries that normally separate regions of the materials,these regions have different crystal structures and or orientations. External surfaces, grain boundaries, phase boundaries are all examples of area defectsOne of the most obvious boundaries is the external surface. Surface atoms are different from those deep in the crystals. Internal atom is fully surrounded by neighboring atoms, however, surface atoms have missing bonds, so, they are in higher energy states than internal atoms. When a solid is used as a catalyst, the catalytic activity depends very much on the surface area per unit mass of the sample.表面是一种面缺陷，表面配位不饱和，其能量高于晶粒内部，对表面化学活性有很大影响。

例如固体催化剂的催化活性就与其表面积有关。

译文：第三种缺陷称为面缺陷。

材料导论中英文讲稿 (18)

Module 2 Unit Cells and Space LatticesIn 2.3 section -the Structure of Crystalline Solids, you are going to learn what are unit cell and space lattice, the seven crystal systems, and the significance of allotropy and polymorphism.The study of crystalline structure is called Crystallography. How can these ordered structures be portrayed? Firstly, we need an axis system; secondly, atoms, ions, molecules can be considered as solid spheres of varying sizes; thirdly, these components’ spatial arrangement can be represented by points at various distances from each other in space.How can we see these crystalline structures? There are many ways. One method is x-ray diffraction.This Figure shows the X-ray diffraction for a single crystal of magnesium. Magnesium has a hexagonal close-packed crystal structure. The diffraction spot pattern in this Figure reflects the hexagonal type symmetry of the magnesium single crystal.译文：在2.3节晶体结构中，你将学习晶胞和空间点阵、七种晶系以及同素异构和多晶态的重要性。

材料导论 (22)

Video 11. Thermal conductivityHere comes the third propertiy of thermal properties, which is thermal conductivity. First is definition. Thermal conductivity refers to the ability of a material to transmit heat. You may ask how a material can transmit heat? It is basically relative to its structure. I will show you the mechanism of thermal conductivity. Heat transport through material based on two mechanisms. It either transfers through the movement of free electrons, or the movement of phonons. Concept of free electron is familiar by people.Metallic materials have electrons can move from one place to the other freely. If you heat a metal, electrons will move through and transmit heat. But for other materials like ceramics or polymers, they don’t have free electrons. Movement of heat has to through something called phonons.译文：这里讲第三种热学性质，热传导。

材料导论（38）

材料导论（38）Video 8: Thermoplastics and ThermosetsToday, we will talk about thermoplastics and thermosets.Thermoplastics, also called thermoplastic polymers. Here, thermo- means heat, plastic means moldable, or workable.As the name suggests, under the action of heat and pressure, thermoplastics become soft gradually and finally flow like liquid. Upon cooling, the polymers become hard and take or adopt the shape of the mold, form a shape like that of the mold or container. Usually, Thermoplastics can withstand several of these heating and cooling cycles without suffering any structural breakdown. The shape of a product can be changed, that is, the product can be remolded. This behavior is similar to that of candle wax. Because of this property, we can easily recycle or reuse the waste or discarded plastic bags or bottles. Usually, thermoplastics are formed by addition polymerization. Examples of common thermoplastic polymers include polyethylene, polystyrene, and nylon.今天讲热塑性和热固性聚合物。

材料导论第八章

材料导论第⼋章Module 8For 8-1 to 8-5A. biomaterialB. biocompatibilityC.biofunctionalityD. in vitro testingE. in vivo testing8-1 Any substance or combination of substances synthetic or natural origin, which can be used for any period of time, as a whole or as a part of a system which treats, augments, or replaces any tissue, organ, or function of the body.A biomaterial8-2 The ability of a material to perform with an appropriate host response in a specific application.B biocompatibility8-3 The ability to accomplish the predetermined functions of the medical device in a living organism.C.biofunctionality8-4 A term refers to that biomaterials are evaluated for biofunctionality and biocompatibility in a test tube or in a controlled artificial environment.Din vitro testing8-5 A term refers to that the biofunctional and biocompatible experimentation of biomaterials in done in or on the living tissue of a whole living organism.E in vivo testing8-7 What are the major groups of biomaterials?Metallic biomaterials,ceramic biomaterials,polymeric biomaterials,composite biomaterials8-12 How are biomaterials classified according to the biocompatibility assessment of a biomaterial?In vitro testing of biomaterialsIn vivo testing of biomaterials8-65 Polymers possess labile functional groups accessible to biological or nonbiological mechanisms of degradation. Biodegradable polymers (P414)8-66 The destruction and assimilation of organic polymers by living organisms and their enzymes, particularly fungi and bacteria.Biodegradation (P 414)8-67 A physical phenomenon upon which the release of degradable products leads to the mass losses of the polymer matrices.Erosion (P 414)8-68 The erosion occurs under the circumstance when the rate of bond cleavage is remarkably lower than the rate of water penetration, and the backbone cleavage of the polymer occurs uniformly throughout the interior of the device.Bulk eroding8-69 The erosion occurs under the circumstance when the rate of bond cleavage is remarkably higher than the rate of water penetration, and only the polymer at/near the surface is degraded.Surface eroding8-85 What are the chemical repeating units for alginate? Which repeating unit in the alginate is favorable for the formation of firm gels?β-D-mannuronic (M), α-L-guluronic acid (G) joined by 1,4-glycosidic linkage (P406)A high proportion of guluronic acid (a low M/G ration) in the polymer gives an alginate that forms firm gels8-99 How does erosion differ from degradation?The term “degradation” specifically refers to bond cleavage, whereas “erosion” refers to depletion of material.补充：1、What are the advantages of biopolymers over synthetic polymers?Biopolymers can be degraded by enzymes and therefore they are biodegradable, which provides an additional advantage over the use of non-biodegradable synthetic polymers.2、What are the differences between surface erosion and bulk erosion?Surface eroding polymers undergo erosion at constant velocity at any time during erosion. The erosion occurs under the circumstance when the rate of bond cleavage is remarkably higher than the rate of water penetration, and only the polymerat/near the surface is degraded.Bulk eroding polymers have no constant erosion velocity, and usually do not erode for long periods of time after which erosion sets in spontaneously. The erosion occurs under the circumstance when the rate of bond cleavage is remarkably lower than the rate of water penetration, and the backbone cleavage of the polymer occurs uniformly throughout the interior of the device.3、What are the compositions and sources of the common naturally occuring biopolymers cellulose, starch,alginate, chitin and collagen?Cellolose纤维素(P399)Starch 淀粉(P400)is a homopolysachride whose monomer is a-D-glucose. Most of these glucose monomers are linked by hemiacetal bonds, called glucosidic linkages ora-1-4linkages,a few are linked between the hydroxyls on carbons by a-1-6linkages Alginate 藻朊酸盐(P406)exist in brown algae(seaweed and kelp)Chitin 甲壳素(P402)is one of the most abundant polysaccharides found in nature .it is found naturally in the shell of crustaceans such as crabs and shrimps, insect exoskeletons, fungal cell walls,microfauna and planktonCollagen 胶原(P410)is widely distributed in skin bones teeth tendons eyes and most other tissues and organs and is involved in various cells in terms of their functional expression.4、What is the classification of biomaterials three generations of?1. Off-the-shelf materials with a common feature of biological “inertness”.2. Exhibit clinically relevant controlled chemical breakdown and resorption in the physiological environment.3. Are being designed to simulate specific cellular responses at molecular level.⼀、补充教材：Module55-1，Understand the classification of polymers based on the types of monomers.5-5，5-6，5-8，5-9，5-11，5-13，5-17，5-21，5-24 (part I)，5-26，5-28，5-37，5-40，5-44 (carbon blacks )，5-45，5-46，5-49，5-52，5-54，新补充：1. Typical rubbers and plastics and their corresponding abbreviations.2. Define the terms of caulks and geosynthetics?3. What are the advantages of polymers over ceramics?4. The processing methods for thermosetting plasticsModule77-1，7-5，7-6，7-8，7-12，7-13，7-14，7-16，7-17，7-18，7-19，7-26，7-27，7-28，7-30，7-32，7-34, 7-35, 7-37，7-38，7-39, 7-45, 7-47，7-51, 7-52，7-53, 7-57，7-59，7-66最新补充：1. How is the orientation of fiber related to fiber loading and processing methods of composites?2. The abbreviations and the Chinese names of the common composites, prepregs and molding methods of composites.3. Understand the terms of laminate and the particulate composites.4. What is the processing method for the composite parts with round or oval inner surfaces?5. Compare the strength of the same materials in fiber and bulk forms.6. The relation of composite processing to the application of heat and pressure.Module88-1，8-2，8-3，8-4，8-5，8-7, 8-12，8-65，8-66，8-67，8-68，8-69，8-85，8-99最新补充：1. What are the advantages of biopolymers over synthetic polymer?2. What are the differences between surface erosion and bulk erosion?3. What are the compositions and sources of the common naturally occurring biopolymers such as cellulose, starch, alginate, chitin and collagen?4. What is the classification of biomaterials three generations of?⼆、教材（已学部分）1. Glossary of each Module2. Self-assessment of each Module。

材料导论中英文讲稿 (29)

Video 7. CreepNow, Let’s study creep. If you learn creep, you will know there are some similarities between creep and fatigue in their measuring methods. When we measure fatigue property, we apply cyclic loadings. But when we measure creep, we apply a loading to a sample permanently or for a long time. The similarities are that the materials all encounter deformations.译文：我们学习儒变。

学习儒变，你将知道儒变和疲劳的测试方法比较类似。

当测量疲劳性能时，我们加以周期性力。

当测量儒变性能时，我们施加恒定的外力，并保持足够长的时间。

相同的是：材料都发生了形变。

Let us study creep(蠕变). The creep property of material tells (you) deformation (of a material) happens when a material is underwent a constant loading for considerably long time. First I give you definition of creep. It is a slow process of plastic deformation that takes place when a material is subjected to a constant condition of loading (stress) below its normal yield strength. So based on this definition, you will know that. Firstly, creep happens at a very long period of time. Secondly, the loading is constantly applied to the material. Finally, the loading should be lower than the yield strength because otherwise, the material will deform in a very short time.译文：让我们学习儒变。

材料科学与工程基础英文版试题

材料科学与工程基础”考试试题–英文原版教材班（注：第1、2、3题为必做题；第4、5、6、7题为选择题，必须二选一。

共100分）1. Glossary (2 points for each)1) crystal structure: The arrangement of the atoms in a materialinto a repeatable lattice.2) basis (or motif): A group of atoms associated with a lattice.3) packing fractor: The fraction of space in a unit cell occupiedby atoms.4) slip system: The combination of the slip plane and the slipdirection.5) critical size: The minimum size that must be formed by atomsclustering together in the liquid before the solid particle is stable and begins to grow.6) homogeneous nucleation: Formation of a critically sized solidfrom the liquid by the clustering together of a large number of atoms at a high undercooling (without an external interface).7) coherent precipitate:A precipitate whose crystal structure andatomic arrangement have a continuous relationship with matrix from which precipitate is formed.8) precipitation hardening: A strengthening mechanism thatrelies on a sequence of solid state phase transformations in a dispersion of ultrafine precipitates of a 2nd phase. This is same as age hardening. It is a form of dispersion strengthening.9) diffusion coefficient: A temperature-dependent coefficientrelated to the rate at which atom, ion, or other species diffusion.The DC depends on temperature, the composition and microstructure of the host material and also concentration of the diffusion species.10) uphill diffusion: A diffusion process in which species movefrom regions of lower concentration to that of higher concentration.2. Determine the indices for the planes in the cubic unit cell shown in Figure 1. (5 points)Fig. 1Solution : A(-364), B(-340), C(346). 3. Determine the crystal structure for the following: (a) a metal with a 0 = 4.9489 Å, r = 1.75 Å and one atom per lattice point; (b) a metal with a 0 = 0.42906 nm, r = 0.1858 nm and one atom per lattice point. (10 points) Solution : (a)fcc; (b) bcc. 4-1. What is the characteristic of brinell hardness test, rockwell hardness test and V ickers hardness test? What are the effects of strain rate and temperature on the mechanical properties of metallic materials? (15 points) 4-2. What are the effects of cold-work on metallic materials? How to eliminate those effects? And what is micro-mechanism for the eliminating cold-work effects? (15 points) 5-1. Based on the Pb-Sn-Bi ternary diagram as shown in Fig. 2, try to (1)Show the vertical section of 40wt.%Sn; (5 points) (2) Describe the solidification process of the alloy 2# with very low cooling speed (including phase and microstructure changes); (5 points) (3)Plot the isothermal section at 150o C. (5 points)5-2. A 1mm sheet of FCC iron is used to contain N 2 in a heated exchanger at 1200o C. The concentration of N at one surface is 0.04 atomic percent and the concentration at the second surface is 0.005 atomic percent. At 1000 oC, if same N concentration is demanded atFig. 2the second surface and the flux of N becomes to half of that at 1200o C, then what is the thickness of sheet? (15 points)6-1. Supposed that a certain liquid metal is undercooled until homogeneous nucleation occurs. (15 points)(1)How to calculate the critical radius of the nucleus required?Please give the deduction process.(2)For the Metal Ni, the Freezing Temperature is 1453︒C, the LatentHeat of Fusion is 2756 J/cm3, and the Solid-liquid Interfacial Energy is 255⨯10-7J/cm2. Please calculate the critical radius at 1353︒C. (Assume that the liquid Ni is not solidified.)6-2. Fig.3 is a portion of the Mg-Al phase diagram. (15 points) (1)If the solidification is too rapid, please describe the solidificationprocess of Mg-10wt%Al alloy.(2)Please describe the equilibrium solidification process ofMg-20wt%Al alloy, and calculate the amount of each phase at 300︒C.Fig. 37-1. Figure 4 shows us the Al-Cu binary diagram and some microstructures found in a cooling process for an Al-4%Cu alloy. Please answer following questions according to this figure. (20 points)Fig. 4 (1)What are precipitate, matrix and microconstituent? Please point them out in the in the figure and explain. (2)Why is need-like precipitate not good for dispersion strengthening? The typical microstructure shown in the figure is good or not? why? (3)Please tell us how to obtain the ideal microstructure shown in this figure. (4)Can dispersion strengthened materials be used at high temperature? Please give the reasons (comparing with cold working strengthening) 7-2. Please answer following questions according to the time-temperature-transformation (TTT) diagram as shown in Fig. 5. (20 points) (1)What steel is this TTT diagram for? And what means P, B, and M in the figure? (2)Why dose the TTT diagram exhibits a ‘C’ shape? (3)Point out what microconstituent will be obtained after austenite is cooled according to the curves I, II, III and IV . (4)What is microstructural difference between the curve I and the curve II? (5)How to obtain the steel with the structure of (a) P+B (b) P +M+A (residual) (c) P+B+M+A (residual) (d) F ull tempered martensite If you can, please draw the relative cooling curve or the flow chart of heat treatment.Fig. 5 III III IV。

材料导论中英文讲稿 (30)

Video 8. HardnessHardness. If I ask you what is the hardest material around the world? What is your answer? I believe most people will say ‘diamond’. Why you think diamond is hard? Because you can use diamond to scratch other material without any damage.Here comes the definition of hardness. It is a measure of a material’s resistance to penetration抗穿刺(local plastic deformation) or scratching抗划伤. 硬度就是衡量一个材料抗穿刺、抗划伤的能力。

Also, hard material has good resistance to wire or abrasion. 越坚硬的材料耐磨性也越强。

So, that is the reason why you use diamond to make cutting tools. 一些刀具或钻头往往用钻石类坚硬的材料制备。

译文：硬度。

如果我问你们什么是世界上最硬的材料？你会怎么回答？我相信大多数人会说：“钻石”。

为什么你们认为钻石最坚硬？因为你们可以用钻石划伤其他材料，而自身不受损坏。

硬度的定义是：硬度是衡量材料对穿刺或划伤的抵抗能力。

越坚硬的材料耐磨性越强，因此一些道具或钻头往往用钻石这种坚硬材料制备。

Here comes a measuring method to hardness. How can you quantitatively measure hardness? 你怎么来测量硬度呢？Based on the definition, we know hardness means the resistance to penetration or scratching. Therefore, the measuring methods are also corresponding to these two types of properties. You can either measure the degree of penetration, using some specifically selected indenters. There are four different measurements for hardness, where are called brinell hardness, Vickers hardness, Rockwell hardness and knoop hardness. You can also measure the resistance of scratching which is called Mohs hardness and most people are familiar with that (measuring method). There is another measuring method that is called rebounding method. It is called Scleroscope test.译文：这里给出一个测量硬度的方法。

材料概论(双语)智慧树知到课后章节答案2023年下东华理工大学

材料概论（双语）智慧树知到课后章节答案2023年下东华理工大学东华理工大学第一章测试1.结构材料和功能材料是依据材料组成来划分的。

答案:错2.Metals in general have high electrical conductivity, high thermal conductivity,and high density.答案:对3.金属材料中不含非金属元素。

答案:错4.铜是黑色金属。

答案:错5.锌是有色金属。

答案:对6.以下哪种是黑色金属？答案:铁第二章测试1.哪种原料为陶瓷体提供玻璃相？答案:长石2.哪种原料为陶瓷体提升白度？答案:石英3.陶瓷瓶的制作一般采用注浆成型。

答案:对4.干燥的方法主要排除坯体中的哪类水？答案:自由水5.Glass is a non-crystalline product of fusion which has been cooled to a rigidcondition.答案:对6.水泥生产用回转窑的高端是进料口，低端是燃料进口。

答案:对7.下列哪个不是硅酸盐水泥的化学组成？答案:氧化钠8.下列哪些是硅酸盐水泥的矿物组成？答案:铝酸三钙;硅酸三钙;硅酸二钙第三章测试1.高碳钢的碳含量在百分之零点六到百分之一点四之间。

是一类硬度最大、强度最高、延性最差的碳钢。

答案:对2.哪种元素是不锈钢不锈的原因？答案:铬3.黄铜的主要合金元素是什么？答案:锌4.青铜的主要合金元素是什么？答案:锡5.黄铜的强度比青铜要高。

答案:错6.相的状态可以是固体、液体，或者是气体。

可以是一类纯物质或包含几种组成的溶液。

答案:对7.相图是用以描述一个材料系统在不同温度、压力和组成下存在什么相的图形表示。

答案:对8.二元匀晶合金体系的两种成分在固液两态下能完全互溶。

答案:对9.共析钢的碳含量是多少？答案:0.8%10.Substitutional solid solution是指间隙固溶体。