倒挡碟簧断裂原因分析  

Analysis on Cause of Reverse Disc Spring Breaking

作　　者：罗慧琪 陈启略 缪海遒 黄秋庆 LUO Huiqi;CHEN Qilue;MIAO Haiqiu;HUANG Qiuqing(Liuzhou Saike Technology Development Co.,Ltd.,Liuzhou 545005,Guangxi China;SAIC-GM-Wuling Automobile Co.,Ltd.,Liuzhou 545007,Guangxi China)

机构地区：[1]柳州赛克科技发展有限公司,广西柳州545005 [2]上汽通用五菱汽车股份有限公司,广西柳州545007

出　　处：《热处理》2022年第4期54-56,共3页Heat Treatment

摘　　要：某公司变速箱空挡试验20万次后其51CrV4钢倒挡碟簧断裂。对断裂的倒挡碟簧进行了宏观检查、表面硬度检测、金相检验、化学成分分析及断口检验。结果表明:断裂倒挡碟簧的表面硬度、显微组织和化学成分均符合要求,具有典型的疲劳断裂特征;冲压模的齿槽处有细微缺口,使倒挡碟簧冲压成形时产生折叠。正是折叠处产生应力集中效应导致倒挡蝶形弹簧疲劳断裂。Reverse disc spring of 51 CrV4 steel for a gear box broke after empty testing 200,000 times in a company. Macro-check, surface hardness measurements, metallographic examination, chemical composition analysis, and fracture testing were carried out for the broken reverse disc spring. The results showed that(a) the broken reverse disc spring displayed surface hardness, microstructure and chemical composition which all conformed with the requirements, and was characteristic of typical fatigue fracture;and(b) the fine notch was found at stamping die gullet, caused the reverse disc spring to form wrinkle during stamping. It was stress concentration effect at the wrinkle that resulted in fatigue fracture of the reverse disc spring.

关 键 词：折叠 疲劳断裂 冲压模具 

分 类 号：TG115[金属学及工艺—物理冶金]