On the Rockwell Hardness Test of a Thin Metal Sheet : Effect of Anvil

Abstract

Concerning the superficial hardness test of a thin metal sheet, the effects of spot-anvils made of steel or diamond are investigated. As the sheet becomes thinner, the difference between the measured hardness values obtained upon steel anvil and diamond anvil is significant. We can find a limiting ratio between the thickness of specimen and the depth of indentation. When the ratio becomes larger than this value, the effect of anvil is not recognized any more. It is adequate to use the diamond anvil instead of the steel anvil for the stable and reliable hardness test of thin metal sheets.