不锈钢螺柱的断裂失效现象及机制探讨  

Fracture Failure Analysis of Stainless Steel Bolt

作　　者：曹洪治[1] 桑玮玮[2] 马峰[1] 陈华辉[1] 

机构地区：[1]中国矿业大学(北京)机电与信息工程学院材料系,北京100083 [2]河南工程学院机械工程系,河南郑州451191

出　　处：《润滑与密封》2011年第8期89-92,共4页Lubrication Engineering

基　　金：中国矿业大学(北京)青年科研基金资助项目

摘　　要：研究常用螺柱的断裂失效现象。采用扫描电子显微镜(SEM)Hitachi S-3400N对螺柱断口形貌进行观察,采用能谱仪(EDX)对第二相夹杂物进行分析;对螺柱进行受力分析,确定扭转断裂所需的应力,发现螺柱在低于其正常切应力状态下发生了扭转断裂失效;通过应力计算、形貌观察分析螺柱的断裂失效过程机制及失效机制。结果表明:存在于螺纹表面上的裂纹是导致螺柱扭转断裂的主要原因,即在长期使用过程中,螺柱表面因疲劳产生微裂纹,在剪切外力作用下,微裂纹扩展,导致螺柱在低于正常应力状态下,发生了断裂失效。断裂过程中,材料发生了剪切、拉伸、摩擦等现象。The fracture failure of the bolt in common use was studied. The patterns of the fracture surface and the second phase impurities were studied with SEM （ Scanning Electron Microscope） and EDX （ Energy Dispersive X-ray Analysis）. The stress resulted in the the fracture of bolt was determined by mechanics analysis, it was found that the fracture failure happened under the normal shear stress. The failure process and mechanism of the boh were analyzed through the morphology observation and stress calculation. The results indicate that the fatigue crack on the bolt surface plays an important effect on the fracture failture. The micro-cracks on the holt surface are genretated from the fatigue during the long-time application. Under the external shear force, the micro-cracks expand and lead to the fracture failure under the given shear stress. Shearing, tension and friction occurr during the faihure process.

关 键 词：材料失效与保护 不锈钢 断裂 疲劳 

分 类 号：TG142[一般工业技术—材料科学与工程]