摘要
某车辆在一次轮侧碰撞事故中,其转向拉杆在与梯形臂连接的螺纹处发生断裂。通过宏观检查、化学成分分析、显微组织分析、断口扫描电镜分析以及建立其力学模型进行稳定计算并综合分析后认为,该拉杆具有早期缺陷,很大程度上降低了其安全系数。在有缺陷的情况下,横拉杆的稳定极限载荷为24.41kN,承载能力较其正常稳定极限载荷50.23kN下降了51.4%。该转向拉杆在此次事故中受到冲击载荷,在横截面积最小处即连接螺纹处发生失稳,最终断裂失效。
An automotive steering tie rod fractured in a collision accident. Macro examination, chemical composition analysis, microstrueture examination, and fracture surface analysis by SEM were carried out on the fractured steering tie rod. In addition, a mechanical model was established, and the stability analysis calculation was carried out according to the model. The results showed that there were early defects in the steering rod, and as a result, the safety coefficient of the steering rod greatly declined. The ultimate beating capacity of the defective steering rod was 24.41kN, declining by 51.4% , compared with the normal ultimate beating capacity of 50.23kN. In this accident, the defective steering rod was acted on by impact load, and eventually, it fractured at the point under the effect of greatest pressure.
出处
《失效分析与预防》
2008年第4期28-32,共5页
Failure Analysis and Prevention
基金
北京工业大学研究生科技基金项目(Ykj-2007-1689)
关键词
转向拉杆
失效分析
早期缺陷
失稳
steering tie rod
failure analysis
early defects
instability
