金属材料布氏硬度试验中测量不确定度的评定

Evaluation of Measuring Uncertainty in Metallic Material Brinell Hardness Test

以45#调质钢硬度试验为例,研究了金属材料布氏硬度试验中测量不确定度的评定。布氏硬度试验测量不确定度的主要来源有试验力误差、压头直径误差、压痕直径测量误差、硬度计示值误差、试样表面质量以及数据修约引起的不确定度。结果表明,合成标准不确定度为1.56H BW,扩展不确定度为3H BW,45#调质钢的测试硬度HBW为(199±3),k=2。

The evaluation of measuring uncertainty in metallic material Brinell hardness test is studied by testing the hardness of the 45 quenched and tempered steel. The main sources that affect measuring uncertainty in the hardness test include the error of the test load, the error of the indenter diameter, the measuring error of the indentation diameter, the error of the hardness testing machine, the surface quality of the sample and the uncertainty of correcting data. The results show that the combined standard uncertainty is 1.56HBW, the expanded uncertainty is 3HBW and the Brinell hardness of the 45 quenched and tempered steel is HBW(199±3),k=2.