汽车空心齿轮轴台架疲劳断裂原因分析  

Analysis of fatigue failure of automobile hollow gear shaft in bench test

作　　者：金国忠 汪开忠[1] 胡芳忠[1] 杨少朋 杨志强[1] 陈世杰[1] Jin Guozhong;Wang Kaizhong;Hu Fangzhong;Yang Shaopeng;Yang Zhiqiang;Chen Shijie(Maanshan Iron and Steel Co.,Ltd.,Maanshan Anhui 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：《金属热处理》2022年第11期266-270,共5页Heat Treatment of Metals

基　　金：工信部工业强基项目(TC180A3Y1/分包号:14)。

摘　　要：通过光学显微镜、显微硬度计和扫描电镜对一种新型空心齿轮轴台架疲劳断裂行为进行分析。结果表明,空心齿轮轴在过渡弧位置断裂。零件材料的化学成分、奥氏体晶粒度、非金属夹杂物均满足设计要求,但有效渗碳层深度偏设计要求下限。计算结果表明,空心齿轮轴过渡弧半径应大于3.16 mm,较小的过渡弧半径加剧渗碳过程中的“尖角效应”,导致过渡弧处碳化物粗大并引起应力集中,这可能是疲劳寿命较低的原因之一。CAE软件模拟结果表明,过渡弧处存在明显的应力集中现象,表面最大应力超过零件表面的许用应力,这可能是空心齿轮轴失效的另一个原因。零件表面最大应力随空心尺寸的增加而增加,最大空心尺寸应小于?17.1 mm。The fatigue failure behavior of new type hollow gear shaft in bench test was analyzed by means of optical microscope,microhardness tester and scanning electron microscope.The results show that the transition arc position is the failure position of the hollow gear shaft.The chemical composition of part material,austenite grain size and non-metallic inclusions all meet the design requirements,while the effective carburized layer depth just approaches the lower limit of the design requirements.The calculation results show that the radius of the transition arc of the hollow gear shaft should be greater than 3.16 mm,and during the carburizing the smaller transition arc radius is prone to the"sharp angle effect",resulting in coarse carbides and stress concentration,which may be one of the reasons for the low fatigue life.The simulation results of CAE software show that there is obvious stress concentration at the transition arc,and the maximum stress on the surface exceeds allowable stress of the part,which may be another reason for failure of the hollow gear shaft.The maximum stress on surface of the part increases with the increase of hollow size.The maximum size of the hollow should be less than?17.1 mm.

关 键 词：空心齿轮轴 渗碳 尖角效应 软件模拟 

分 类 号：TG156[金属学及工艺—热处理]