不锈钢拉杆断裂失效分析

Failure analysis on fracture of stainless steel tie rod

  • 摘要: 某试制车型的不锈钢拉杆,在装配完成静置24h后发生了断裂失效,断裂位置在不锈钢拉杆的焊接接头处。通过宏观观察、扫描电镜分析、化学成分分析、金相与硬度检测等方法对不锈钢拉杆的失效原因进行了分析。结果表明:不锈钢拉杆的失效模式为氢脆断裂,拉杆材料中碳含量过高、焊接过程中在焊缝与热影响区出现马氏体组织,是导致氢脆断裂的根本原因。

     

    Abstract: The stainless-steel tie rod of a trial-produced vehicle model fractured after being left stationary for 24 hours after assembly. The fracture occurred at the welded joint of the stainless-steel tie rod. The failure causes of the stainless-steel tie rod were analyzed through methods such as macroscopic observation, scanning electron microscopy analysis, chemical composition analysis, metallographic and hardness testing. The results show that the failure mode of the stainless-steel tie rod is hydrogen-induced cracking. The excessively high carbon content in the tie rod material and the appearance of martensite structure in the weld and heat-affected zone during the welding process are the root causes of the hydrogen-induced cracking.

     

/

返回文章
返回