Rockwell Hardness Tester
Qualified Member | Trained By |
---|---|
Dean Anderson | Danger committee |
Everett Wilson | Danger committee |
Rockwell Hardness
The Rockwell scale is a hardness scale based on indentation hardness of a material. The Rockwell test determines the hardness by measuring the depth of penetration of an indenter under a large load compared to the penetration made by a preload. There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, HRB, HRC, etc., where the last letter is the respective Rockwell scale. When testing metals, indentation hardness correlates linearly with tensile strength. This important relation permits economically important nondestructive testing of bulk metal deliveries with lightweight, even portable equipment, such as hand-held Rockwell hardness testers.
Notes
As of October 2015, the machine shop doesn't have a diamond indenter for the Rockwell C scale -- but we do have spherical indenters for Rockwell B.
Keep the dust cover on. Use calibration discs if you care about your results. Accessories for the tester are in the tan colored cabinet.
Resources
This video shows another machine but it has a good explanation of the test: https://www.youtube.com/watch?v=G2JGNlIvNC4
Source for diamond indentor: http://www.westportcorp.com/dpc1.html