The Wilson/Yamamoto test blocks are manufactured from a high purity alloy steel and feature guaranteed uniformities as low as 0.2 HRC. Available in Rockwell "C" hardness levels from HRC 25 to HRC 62, they are calibrated according to ASTM E-18 methods. The blocks measure 64 mm dia. x 15 mm thick. In addition to Rockwell "C", they are also available in a full range of hardnesses within the commonly used Rockwell scale.
Hardness Test Blocks
November 10, 2000