Rockwell Hardness Block Ring 0.2kg/block ¬¶60׬¶10×10MM
60-70HRC (ring alloy)
50-55HRC (ring alloy)
40-50HRC (ring alloy)
30-35HRC (ring alloy)
20-30HRC (ring alloy)
60-70HRA (ring alloy)
70-85HRA (ring alloy)
85-95HRB (ring alloy)
60-70HRB (ring alloy)
HR - Rockwell hardness block
Rockwell hardness (HR-) is an index of hardness value determined by the depth of indentation plastic deformation.
Take 0.002 mm as a unit of hardness.
When HB>450 or the sample is too small, the Brinell hardness test cannot be used and the Rockwell hardness measurement is used instead.
It uses a diamond cone with an apex angle of 120° or a steel ball with a diameter of 1.59 and 3.18mm, which is pressed into the surface of the material to be tested under a certain load, and the hardness of the material is obtained from the depth of the indentation.
According to the hardness of the test material, it is expressed in three different scales:
HRA: It is the hardness obtained by using a 60kg load and a diamond cone indenter. It is used for material buckets with extremely high hardness (such as cemented carbide, etc.).
HRB: It is the hardness obtained by using a steel ball hardened with a load of 10OKg and a diameter of 1.59mm, and is used for materials with lower hardness (such as annealed steel, cast iron, etc.).
HRC: It is the hardness obtained by using a 150kg load and a diamond cone indenter, and is used for materials with high hardness (such as quenched steel, etc.).
Rockwell Hardness Block For 20-95 HRC HRA HRB Rockwell Hardness Calibration Standard Block Standard Rockwell Hardness Block Test