摇臂轴螺纹延迟断裂原因分析及预防措施
Analysis and Prevention Measures of Pitman Shaft Thread Delayed Fracture
马卫东1, 王书艳2, 王新翠2
点击：3566次 下载：0次
作者单位：1. 南京航空航天大学 机电学院, 江苏 南京 210000; 2. 豫北汽车动力转向器有限公司, 河南 新乡 453003
中文关键字：摇臂轴； 延迟断裂； 感应回火
英文关键字：pitman shaft; delayed fracture; induction tempering
中文摘要：通过对转向器摇臂轴的热处理、硬度、受力情况、断口形貌等因素进行分析，认为该部位的断裂是由于零件含氢引起的延迟断裂。断裂部位较高的硬度、零件中的氢含量以及断裂部位的应力集中情况是影响延迟断裂的主要因素。同时，对目前普遍采用的感应回火和局部防渗碳保护工艺的特点进行了分析，认为感应回火能同时有效地降低表面和心部硬度，是预防摇臂轴螺纹延迟断裂的有效方法。
英文摘要：The heat treatmeat process, hardness, applied force and fractographic appearances of the steering gear pitman shaft were analyzed. The crack is considered to be delayed fracture induced by hydrogen. The main factors that influenc the fracture is higher hardness, hydrogen content and stress concentration on the fracture region. In the meantime, the two kinds of processes that reduce hardness on thread:induction tempering and localized anti-carburization are analyzed. It is concluded that induction tempering is an effective way to avoid delayed fracture on pitman shaft thread.