Hardness relationship between eNM3A10 and conventional hardness scales

Abstract

Small ball rebound hardness eNM3A10 is a next-generation rebound hardness test with features not existing in conventional rebound hardness tests: reduced mass effect of hardness and satisfying the similarity rule of hardness (Minimum thickness of steel specimen is around 5 mm). Regarding features other than these two, because this new test method will be used mainly to evaluate the hardness of metallic specimens, it would be necessary to clarify the relationship between the eNM3A10 hardness value (coefficient of restitution e) and the hardness values of the conventional hardness tests, such as Rockwell, Vickers, Brinell and Shore, by the type of tested material. To achieve that, we tested the hardness of standardized hardness blocks made of steel and copper alloy as well as aluminum alloy specimens by the eNM and conventional hardness test methods to compare their hardness values. The relationship of hardness values between eNM3A10 and the conventional scales was found to be fairly correlative.

Keywords

• Hardness
• Rebound hardness
• eNM
• Hardness conversion