Determine the Brinell hardness of steel at different depth,analysis the depth of determination how to affect hardness,and certify than depth of decarburization is the reason of noreliability of the hardness by metallograph.

• 通过对中厚板不同厚度处布氏硬度的测量 ,分析测量深度对硬度的影响 ,并通过金相分析进一步证实表面脱碳层的存在是造成硬度值不稳定的原因。