A common rule of thumb for choosing a Rockwell scale is to choose the scale that specifies the biggest load and the largest indenter possible without going beyond permitted operation limits and taking into account circumstances that could affect the test outcome. These circumstances include testing on cylindrical specimens, test impressions that are too close to the specimen’s edge or another impression, and test specimens that are thinner than the required minimum thickness for the depth of indentation.

To achieve accurate loading, the test axis should also be within two degrees of perpendicular. Furthermore, neither the test sample nor the tester should be deflected during the loading application by factors such as dirt under the test specimen or on the elevating screw. The surface finish must be kept spotless, and any decarburization after heat treatment must be eliminated.

For testing on a specific Rockwell scale, sheet metal can be too thin and too brittle to pass without going over the minimum thickness criteria and possibly denting the test anvil. In this situation, a diamond anvil can be utilized to consistently impact the outcome.

NextGen’s Ultrasonic Contact Impedance Hardness Tester – UH200 main line measuring range is HB: 85-650; HV 10-2980 HV; HRC 20-70; HRB: 41-100; HRA: 61-85.6 HS: 34.2-97.3; Mpa: 255-2180N/mm.

Click here to obtain a personalized quote!