Rockwell Hardness Testings

In opposite to the other two testing methods (Brinell, Vickers) the hardness is not calculated with the quotient of test load and area of the impression but directly defined with the deepness of penetration into the workpiece.

After a pre-penetration of a conical penetrator, composed of diamond, into the surface of the work piece the actual testing starts. With a higher test load the penetrator is pressed into the work piece for a predetermined time. The remaining depth (tb) that was not reached during the predetermined time, represents the hardness inversely proportional to the depth of penetration:

HRc = 100 – 500 x tb

On HRc-hardness testers the penetration depth and hardness value is displayed immediately after the test.

Advantages and Disadvantages
Immediate displaying of the hardness value - only for hard materials.

Applicable for:
Hardened steels and alloys, hard metals.