在对82MnA钢连铸坯进行常规金相检验时发现,其显微组织中有沿晶界分布的白色相, 采用直读光谱仪、光学显微镜、显微硬度计、扫描电镜及X射线能谱仪等仪器对这种白色相进行了测试和分析。结果表明: 82MnA钢连铸坯中的白色相为磷含量较高的磷化物Fe3P, 其硬度较高, 大多沿晶分布, 具有明显的边界和液态随意凝固特征, 危害性较大。

A kind of white phase distributing along grain boundary were found in the microstructure of 82MnA steel billet when regular metallographic examination. Instruments such as direct-reading spectrometer, optical microscope, micro-hardness tester, scanning electron microscope and X-ray energy spectrometer were used to analyze the white phase. The results show that the white phase in 82MnA steel billet was phosphide Fe3P with high phosphorus content and high hardness. Most of the phosphide Fe3P distributed along the grain boundary and had obvious boundary and liquid optional solidification characteristic, and it was harmful to the steel.