对比了美标和国标中关于维氏硬度试验压痕对角线的判定规则,国标中规定两条对角线之差不应超过平均值的5%,美标中规定如果一条对角线长度的一半大于另一条对角线长度一半的5%,则试样表面可能没有与压头轴线垂直,而NADCAP的审核指导建议则规定一条对角线长度的一半不应超过该条对角线另一半长度的5%。在试验结果的验证过程中,分别对比了上述3种方式对压痕对角线判定的差别,以为维氏硬度测试人员对压痕对角线的判定工作提供参考。

The determination rules of indentation diagonal in Vickers hardness test in American standard and national standard were compared. The national standard stipulated that the difference between the two diagonals should not exceed 5% of the average value. The American standard stipulated that, if half of the length of one diagonal was greater than 5% of half of the length of the other diagonal, the surface of the sample could not be perpendicular to the axis of the indenter, while NADCAP’s audit guidance recommended that half of the length of one diagonal should not exceed 5% of other half of the length of the diagonal. In the verification process of the test results, the differences in the determination of the indentation diagonal by the above three methods were compared respectively, so as to provide reference for the Vickers hardness testers to determine the indentation diagonal.