扭转弹簧氢脆断裂失效分析  

Failure analysis of hydrogen brittleness fracture of torsion spring

作　　者：胡小华[1] 马林[1] 黄飞波[1] 

机构地区：[1]中国人民解放军驻三○二厂军事代表室,江西南昌330024

出　　处：《金属制品》2009年第1期21-23,26,共4页Metal Products

摘　　要：直径0.6 mm的70#冷拔碳素弹簧钢丝镀镉后,制成中径4.0 mm扭转弹簧,在装配时发生断裂。采用能谱分析(EDS)、金相分析和扫描电镜(SEM)对断口进行了宏观和微观检测及分析。结果表明:弹簧在绕制过程中的残余拉应力以及在镀前接触了含氢介质,致使大量的氢残留并呈弥散分布形态,进而形成沿晶裂纹,在外力作用下,导致弹簧沿晶脆性断裂。The mean coil diameter 4.0 mm torsional springs which were made from diameter 0.6 mm, 70# cold drawn carbon spring steel wire after cadmium plating fractured when assembling. The fracture was macro and micro detected and analyzed by means of EDS, metallographic and SEM. The results show that for the residual stress in the spring on the process of winding and the springs contacting with the media which contains hydrogen before plating, a large amount of hydrogen remains in the springs and appears dispersion distribution patterns, which cause the crack along the grain boundary and cause brittle fracture among grain boundary under applied force.

关 键 词：扭转弹簧 断裂 氢脆 镀镉 残余应力 

分 类 号：TG162.74[金属学及工艺—热处理] TG178[金属学及工艺—金属学]