连接底开裂原因分析及改进措施  

Reason analysis of joint bottom cracking and improvement measures

作　　者：石燕 杨有才 褚小菲 李恩省 王翠英 刘振威 史林 SHI Yan;YANG Youcai;CHU Xiaofei;LI Ensheng;WANG Cuiying;LIU Zhenwei;SHI Lin(Henan North Hongyang Mechanical and Electrical Co.,Ltd.,Western Henan Industrial Group,Nanyang 474678,Henan,China)

机构地区：[1]豫西工业集团河南北方红阳机电有限公司,河南南阳474678

出　　处：《金属加工（热加工）》2024年第8期106-109,共4页MW Metal Forming

摘　　要：对失效连接底金相组织、化学成分、裂纹形态等进行理化检测,分析连接底裂纹产生的原因。结果表明:连接底裂纹为淬火裂纹;连接底中心圆柱部与底部过渡弧R角半径较小是主要原因,致使淬火过程中应力集中导致开裂;原材料中心部位组织疏松和冷却速度较快,进一步促进裂纹萌生;通过增大R角、调整热处理工艺来降低淬火应力,从而避免连接底淬火开裂的产生。Metallographic,chemical composition,crack morphology and other physical and chemical tests were carried out to analyze the causes of cracks in the failed joint bottom.The results show that the joint bottom cracks are quenched cracks;The main reason is the small angle radius of the transition arc R between the center cylinder of the joint bottom and the bottom,which leads to the stress concentration during the quenching process leading to cracking;The central part of the raw material is loose and cooled quickly,which further promotes crack initiation;By increase the R angle,adjust the heat treatment process and control the raw material quality,can reduce the quenching stress to avoid the joint bottom quenching cracking.

关 键 词：连接底 淬火裂纹 应力集中 热处理工艺 

分 类 号：TG156.3[金属学及工艺—热处理]