Abstract:
This paper reports work carried out to determine the influence of the ball indenter geometrical errors on the accuracy of Brinell hardness measurements. Indenters with nominal diameters of 1, 2.5, and 5 mm diameter are tested. Fifteen balls are considered for each nominal diameter. The roundness error of each ball is measured. The diameters of the balls were measured by profile projector and the roundness error was measured by CMM machine. The influence of the ball geometry on the accuracy of hardness is investigated. Six calibrated reference hardness-test blocks are used to perform Brinell hardness test using the 45 selected balls. The results show that the roundness error considerably affects the accuracy of the hardness measurement.