客车桥独立悬架的失效分析与改进

Failure Analysis and Improvement of Independent Suspension of Bus Bridge

随着汽车工业的发展,人们对于汽车驾乘舒适性的要求越来越高,汽车底盘的断开式独立悬架结构设计应运而生。文章通过对某客车桥开发阶段疲劳试验后的独立悬架双A型支撑壁的失效分析,发现支撑壁疲劳源处4-7mm的大铸造夹渣是导致其失效的主要原因,同时,C、Al元素含量偏高,基体铸造缩松较多、设计硬度偏高、应力较大均加速了支撑壁的疲劳失效进程。最终,通过调整支撑壁化学成分、铸造时增加陶瓷过滤块挡渣、控制浇注温度减少缩松、降低硬度提高韧性、结构优化降低应力等措施,支撑壁寿命满足要求。

With the development of automobile industry,people’s demand for car ride comfort is getting higher and higher,and the design of the disconnected independent suspension structure of the automobile chassis has emerged.In this paper,through the failure analysis of the independent suspension double A-type support arm after the fatigue test of a bus bridge development stage,it is found that the large casting slag of 4-7mm at the source of fatigue of the support arm is the main cause of its failure,while the C and Al elements are high in content,the design is high hardness.The stress is high and the fatigue failure process of the support arm is accelerated.Finally,the life of the support arm meets the requirements by adjusting the chemical composition of the support arm,increasing the ceramic filter block slag during casting,controlling the pouring temperature to reduce the shrinking,reducing hardness to improve toughness,and optimizing the structure to reduce stress.