球墨铸铁零件高频感应淬火后显微组织异常原因分析  

Cause analysis of abnormal microstructure of nodular cast iron parts after high frequency induction quenching

作　　者：王磊[1] 马录 杨波 张凯 宋阳 王晔 Wang Lei;Ma Lu;Yang Bo;Zhang Kai;Song Yang;Wang Ye(Shaanxi Fast Gear Co.,Ltd.,Xi’an Shaanxi 710119,China)

机构地区：[1]陕西法士特齿轮有限责任公司,陕西西安710119

出　　处：《金属热处理》2021年第6期231-235,共5页Heat Treatment of Metals

摘　　要：某球墨铸铁行星架铸造冒口经高频感应淬火后检测发现,高频感应淬火区存在石墨球化率偏低及铁素体含量过多的现象。经过显微组织及试验对比分析发现:高频感应淬火加热部位石墨形态的异常与冒口处球化剂的缺损及冷却速度相对较慢有关;零件铸后高频感应淬火区位置的铁素体含量过多,而铸后正火并未有效改善该现象,导致高频感应淬火后铁素体含量过多。通过优化铸造工艺,按原工艺进行正火及高频感应淬火,最终得到满足技术要求的产品.Low spheroidization rate and excessive ferrite content was detected in the high frequency induction hardening area of a ductile ironplane carrier riser after induction hardening.Through comparative analysis of microstructure and experiments,the results show that the abnormal graphite morphology in high frequency induction hardening area is related to the defect of nodular at the riser and relatively slow cooling rate.The ferrite content in high frequency induction hardening area after casting is too high,and the normalizing after casting does not effectively improve this phenomenon,which leads to the excessive ferrite content.The qualified part can be obtained by optimizing casting process,normalizing after casting and high frequency induction hardening.

关 键 词：高频感应淬火 组织异常 冒口 冷却速度 奥氏体转变 

分 类 号：TG156.31[金属学及工艺—热处理]