顶尖淬火开裂成因分析

Analysis on Reason of Center Quenching Cracks

采用宏观检验、微观检验、化学分析、硬度测试、扫描电镜分析等方法，对万能工具磨床用大顶尖产生裂纹的原因进行分析。结果表明，顶尖淬火开裂具有热应力型应力引起大型非淬透件所形成的纵劈和横断的特征，而心部严重的网状碳化物和片状珠光体是顶尖产生开裂的主要原因。

This paper analyzes the reason of universal grinding machine＇s big center crack by using macro- inspection, micro- inspection, chemical- analysis, hardness testing, scanning electron microscopy analysis and other methods. The result shows that the center quenching cracks has the characteristics of longitudinal cracking and cross -sectional cracking in the large non -hardened parts, and the main reason is that there were serious netted carbide and sheeting pearlite.