某轻型卡车后桥主动齿轮螺纹轴断裂原因分析  

Fracture Analysis of Threaded Shaft of Driving Gear of Rear Axle of A Light Truck

作　　者：胡义华[1] 程露 黄志超 HU Yihua;CHENG Lu;HUANG Zhichao(Jiangxi Jiangling Chassis Co.,Ltd.,Fuzhou 344000,China;Key Laboratory for Conveyance and Equipment of the Ministry of Education,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]江西江铃底盘股份有限公司,江西抚州344000 [2]华东交通大学载运工具与装备教育部重点实验室,江西南昌330013

出　　处：《热加工工艺》2020年第20期156-160,共5页Hot Working Technology

基　　金：江西省重点研发计划项目(20192BBEL50013,20181BBE50011)。

摘　　要：针对某轻型卡车行驶时出现后桥主动齿轮螺纹轴断裂的早期故障进行了原因分析并提出改进措施。首先,宏观观察了断口失效形式,后对螺纹部分和花键部分进行了金相分析,接着对螺纹部分进行层深及硬度分析和化学分析,最后采用扫描电镜对断裂部位进行了微观组织分析,并且在韧窝区和沿晶区进行了能谱对比,发现各区元素并无明显差异。基于上述分析,最终找出齿轮螺纹轴断裂的原因是主动齿轮螺纹部位高频退火工艺设计不合理。根据失效原因,提出了改进齿轮螺纹轴热处理的方案及实施措施。The cause analysis and improvement measures of the early failure of the screw shaft of the rear axle active gear when a light truck was driving were carried out. First, the fracture failure forms were observed macroscopically, and then metallographic analysis was carried out on the thread part and spline part. Then the depth and hardness of the thread were analyzed and the chemical analysis was carried out. Finally, the fracture position was analyzed by SEM. In the dimple region and the intergranular region, the energy spectra were compared, and no significant difference was found among the elements in each region. Based on the above analysis, it is found that the reason for the fracture of gear thread shaft is that the design of high frequency annealing process in the thread part of active gear is unreasonable. According to the cause of failure, the scheme and implementation measures of improving heat treatment of gear thread shaft are put forward.

关 键 词：主动齿轮 螺纹轴 断裂 高频退火 硬度区 

分 类 号：TG111.91[金属学及工艺—物理冶金]