维氏硬度和洛氏硬度分析
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1. speed is fast
2. few personal errors
3. distinguish small hardness differences
4. indentation is small and tested without damage
5. reproducible(可重复的)
Test Steps
Result: a low value of the contact area so the DPH is higher
Rockwell hardness test
The most widely used hardness among the three methods.
Why is it most widely used?
Advantages: 1. provide a continuous scale of hardness* ，5-1500 2. DPH is independent of load.*
Disadvantages: 1. it is slow and need more time 2. require careful surface preparation of specimen 3. greater chance for personal error in the determination of the diagonal length
Where, P= applied load, kg L=average length of diagonals, mm——microscope θ= angle between opposite faces of diamond =136︒
Advantages and Disadvantages
1. Indenter: clean and well seated
2. Specimen: clean and dry, smooth, and free from oxide（氧化物）. flat surface and perpendicular(垂直) to the indenter thickness:at least 10 times the depth of the indentation
each division ——0.002 mm
reversed： small penetration — high hardness number purely arbitrary(non-dimensional)
Introduction of the test device
total 9 scales ——combinations of 3 types of indenters and 3 different loads 3 types of indenters
Result : an overestimate of the diagonal length and DPH is lower
ຫໍສະໝຸດ Baidu
Barreled Indentation
Reason : ridging or piling up of the metal
Objects: cold-worked metals
the diamond indenter, most extended* 60kg softer material 1.6 mm-diameter steel ball ,100kg
the diamond indenter, hardened steel 150kg
Attentions for hardness test
also named diamond-pyramid hardness
Indenter: a square-base diamond pyramid(方锥形金刚石)
Angle: 136︒
the diamond-pyramid hardness number (DPH)
Definition: the load divided by the surface area of the indentation(压痕) Equation:
Use the depth of indentation to express the hardness, the steps are :
1. apply minor load(初始小载荷)——10kg 2. apply major load——60,100,150kg
3. Unload the major load
The end
Thanks for your attention!
Indentation types
There are three kinds of diamond-pyramid indentations:
a) perfect indentation b) pincushion indentation(枕形压痕) c) barreled indentation（桶状压痕）
Perfect Indentation
made with a perfect diamond indenter square but is just ideal.
Pincushion Indentation
Reason: sinking in of the metal
Objects: annealed metals（退火金属）
Purpose of minor load
1. seat the specimen
2. minimize the amount of surface preparation 3. reduce ridging or sinking in
Introduction of a dial gage
contains 100 divisions
Hardness Test
陈政 0144139001 2015.5.14
Two parts:
1. Vickers Hardness Test(维氏硬度) 2. Rockwell hardness test（洛氏硬度）
Vickers Hardness Test
has fairly wide acceptance for research work,5-1500DPH
Brale indenter (120︒) 1.6 mm-diameter steel ball 3.2 mm -diameter steel ball
60 kg 100kg 150kg
3 different loads
Three frequently-used scales*
Scale Type A scale B scale C scale Application object Indenter and major load
3. Indentation spacing: 3 to 5 times the diameter of the indentation. 4. Speed: standardized*, by adjusting the dashpot(缓冲器)
The end
Thanks for your attention!
2. few personal errors
3. distinguish small hardness differences
4. indentation is small and tested without damage
5. reproducible(可重复的)
Test Steps
Result: a low value of the contact area so the DPH is higher
Rockwell hardness test
The most widely used hardness among the three methods.
Why is it most widely used?
Advantages: 1. provide a continuous scale of hardness* ，5-1500 2. DPH is independent of load.*
Disadvantages: 1. it is slow and need more time 2. require careful surface preparation of specimen 3. greater chance for personal error in the determination of the diagonal length
Where, P= applied load, kg L=average length of diagonals, mm——microscope θ= angle between opposite faces of diamond =136︒
Advantages and Disadvantages
1. Indenter: clean and well seated
2. Specimen: clean and dry, smooth, and free from oxide（氧化物）. flat surface and perpendicular(垂直) to the indenter thickness:at least 10 times the depth of the indentation
each division ——0.002 mm
reversed： small penetration — high hardness number purely arbitrary(non-dimensional)
Introduction of the test device
total 9 scales ——combinations of 3 types of indenters and 3 different loads 3 types of indenters
Result : an overestimate of the diagonal length and DPH is lower
ຫໍສະໝຸດ Baidu
Barreled Indentation
Reason : ridging or piling up of the metal
Objects: cold-worked metals
the diamond indenter, most extended* 60kg softer material 1.6 mm-diameter steel ball ,100kg
the diamond indenter, hardened steel 150kg
Attentions for hardness test
also named diamond-pyramid hardness
Indenter: a square-base diamond pyramid(方锥形金刚石)
Angle: 136︒
the diamond-pyramid hardness number (DPH)
Definition: the load divided by the surface area of the indentation(压痕) Equation:
Use the depth of indentation to express the hardness, the steps are :
1. apply minor load(初始小载荷)——10kg 2. apply major load——60,100,150kg
3. Unload the major load
The end
Thanks for your attention!
Indentation types
There are three kinds of diamond-pyramid indentations:
a) perfect indentation b) pincushion indentation(枕形压痕) c) barreled indentation（桶状压痕）
Perfect Indentation
made with a perfect diamond indenter square but is just ideal.
Pincushion Indentation
Reason: sinking in of the metal
Objects: annealed metals（退火金属）
Purpose of minor load
1. seat the specimen
2. minimize the amount of surface preparation 3. reduce ridging or sinking in
Introduction of a dial gage
contains 100 divisions
Hardness Test
陈政 0144139001 2015.5.14
Two parts:
1. Vickers Hardness Test(维氏硬度) 2. Rockwell hardness test（洛氏硬度）
Vickers Hardness Test
has fairly wide acceptance for research work,5-1500DPH
Brale indenter (120︒) 1.6 mm-diameter steel ball 3.2 mm -diameter steel ball
60 kg 100kg 150kg
3 different loads
Three frequently-used scales*
Scale Type A scale B scale C scale Application object Indenter and major load
3. Indentation spacing: 3 to 5 times the diameter of the indentation. 4. Speed: standardized*, by adjusting the dashpot(缓冲器)
The end
Thanks for your attention!