异型螺纹接销断裂分析及热处理工艺改进  

Fracture Analysis and Heat Treatment Process Improvement of Abnormal Thread Joint Pin

作　　者：廖杭州[1] 夏金财[1] 王斌杰 朱纪广 LIAO Hang-zhou;XIA Jin-cai;WANG Bin-jie;ZHU Ji-guang(Hangzhou Donghua Chain Group Co.,Ltd.,Hangzhou Zhejiang 311102,China)

机构地区：[1]杭州东华链条集团有限公司,浙江杭州311102

出　　处：《热处理技术与装备》2020年第5期51-54,共4页Heat Treatment Technology and Equipment

摘　　要：通过对链条螺纹接销进行宏观和微观形貌、金相组织观察、材质检验以及扭力测试,分析了螺纹接销断裂的性质和原因。结果表明,螺纹接销断裂故障为螺纹R角处疲劳断裂,螺纹R角存在增碳,导致硬度偏高;同时台阶与螺纹过渡处设计缺陷形成应力集中,在螺母的扭力载荷及链条交变载荷共同作用下螺纹R角表面产生裂纹并扩展导致螺纹接销断裂,最终导致链条失效断裂。Through the macro and micro morphology,microstructure observation,material inspection and torsion test,the properties and reasons of the fracture in the threaded joint pin were analyzed.The results show that the fracture failure of threaded joint pin is the fatigue fracture at the R angle of the thread.The R angle of carburization leads to the high hardness.At the same time,the design defects at the transition be-tween the step and the thread forms stress concentration.Under the joint action of the torque load of the nut and the alternating load of the chain,the surface of the R angle of the thread produces cracks and ex-pands,which leads to the fracture of the threaded joint pin,and finally the chain failure and fractures.

关 键 词：链条 螺纹接销 断裂 疲劳 

分 类 号：TG115.21[金属学及工艺—物理冶金]