Measurement Uncertainty Evaluation of Brinell Hardness Test of a Copper Plate

Brinell hardness test was done according to GB/T 231.1-2009 Metallic Materials-Brinell Hardness Test-Part 1:Test Method, and two methods were used to evaluate the measurement uncertainty of Brinell hardness test of a copper plate. The results show that when evaluated by the method of considering the hardness tester maximum permissible error, the results of Brinell hardness test was as fallow:H=(50.7±3.5) HBW2.5/62.5, k=2. When evaluated by the method of considering the hardness tester system error, the results of Brinell hardness test was as fallow:H=(50.7±2.1) HBW2.5/62.5, k=2. The difference of above two methods originated from the maximum permissible error and the system error of the hardness tester.