Uncertainty analysis of measured hardness values of Brinell,Vickers and Rockwell hardness test

The mathematical expressions of Brinell hardness test,Vickers hardness test and Rockwell hardness test were provided firstly.This mathematical expression fit in with the source of hardness values uncertainty evaluation that were annexed in national standard test method.Then the combined uncertainty and its components were fully analyzed,and the uncertainty relational expression between hardness values and indentation metering equipment was induced,which was applied to Brinell hardness testers and Vickers hardness testers,in order that the uncertainty evaluation method of the measured hardness values was understood and used by inspecters.