42CrMoA钢法兰输出轴断裂原因  

Fracture reason of 42CrMoA steel flange output shaft

作　　者：宫秀勉 林孟华 贾六林 GONG Xiumian;LIN Menghua;JIA Liulin(Shanghai TÜV Rheinland Co.,Ltd.,Shanghai 200072,China)

机构地区：[1]莱茵技术(上海)有限公司,上海200072

出　　处：《理化检验(物理分册)》2025年第3期54-58,共5页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某42CrMoA钢法兰输出轴在投入使用后很快断裂。采用宏观观察、化学成分分析、扫描电镜及能谱分析、金相检验等方法分析了输出轴断裂的原因。结果表明:坯料在锻造前期因加热温度过高发生组织过烧是输出轴断裂的主要原因;过烧后,晶界结合力变弱,材料形变能力不足,在截面形变较大的位置形成微裂纹,应力集中和力学性能不符合要求导致裂纹快速扩展,最终该法兰输出轴发生脆性断裂。A 42CrMoA steel flange output shaft fractured quickly after being put into use.The causes of the fracture of the output shaft were analyzed by means of macroscopic observation,chemical composition analysis,scanning electron microscopy and energy spectrum analysis,metallographic examination and so on.The results show that the overburning of the structure due to the high heating temperature in the early stage of forging was the main reason for the fracture of the output shaft.After overburning,the grain boundary bonding force became weak,the material deformation ability was insufficient,and microcracks were formed at the position where the cross-section deformation was large.The stress concentration and mechanical properties did not meet the requirements,resulting in rapid crack propagation.Finally,the flange output shaft brittle fracture occurred.

关 键 词：42CRMOA钢 法兰输出轴 过烧 脱碳 脆性断裂 形变 

分 类 号：TB31[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]