高强度弹簧早期疲劳断裂分析  

Analysis on Early Fatigue Fracture of High-strength Spring

作　　者：龚梦强 汪开忠[1] 尹德福 胡芳忠[1] 金国忠 李爽[1] GONG Mengqiang;WANG Kaizhong;YIN Defu;HU Fangzhong;JIN Guozhong;LI Shuang(Technology Center Maanshan Iron and Steel Co.,Ltd.,Anhui Maanshan 243000,China)

机构地区：[1]马鞍山钢铁股份有限公司,安徽马鞍山243000

出　　处：《失效分析与预防》2025年第1期79-82,共4页Failure Analysis and Prevention

基　　金：安徽省科技重大专项(201903a05020051)。

摘　　要：进口弹簧钢在疲劳寿命检验过程中发生断裂。利用扫描电镜、光学显微镜等手段对断裂试样的宏观缺陷、断口形貌、金相组织等进行系统检测,确定弹簧断裂类型及原因。结果表明:断口部位存在疲劳裂纹,裂纹处有Cu残留;经生产过程分析,在线卷到棒料加工过程中由于存在剥皮螺旋纹,剥皮棒料在进入矫直机时发生高速旋转,粘接二辊矫导套的Cu合金,导致Cu嵌入至银亮棒表面,在银亮棒感应加热时发生沿晶扩散。鉴于Cu熔点较低,建议相关备件材料采用其他材质替代,以避免造成表面质量恶化。Imported spring steel broke during the fatigue life test.Scanning electron microscopy,optical microscope and other means were used to systematically detect the macroscopic defects,fracture morphology and metallographic structure of the fracture samples,and determine the type and cause of spring fracture.The results show that there are fatigue cracks at the fracture site,and there is copper residue at the crack.According to the analysis of the production process,due to the existence of peeling spiral pattern in the processing process of wire coil to bar,in the straightening link,the stripping bar material rotates at high speed when it enters the straightening machine,and the copper alloy of the two-roller orthodox sleeve is bonded to the surface of the silver bright rod after the straightening process,and the silver bright rod is diffusion along the grain when it is inductively heated.Considering the low melting point of copper,it is recommended that machining plants replace copper related spare materials with other materials to avoid surface quality deterioration.

关 键 词：弹簧钢 疲劳断裂 剥皮 沿晶 

分 类 号：TG115.21[金属学及工艺—物理冶金] TG157[金属学及工艺—金属学]