某型飞机主起落架活塞杆裂纹分析

Analysis of Cracks on Piston Rod of Main Landing Gear of Certain Aircraft

主起落架供飞机起飞、着陆、滑跑、停放使用,主起落架的活塞杆在压缩时承受油液的压力和冲击力,在使用过程中会出现活塞杆裂纹而失效的情况。文中对活塞杆裂纹进行失效分析。分析结果表明,活塞杆失效是氢脆导致的,镀铬或镀铬后的除氢处理工艺控制不当是造成氢脆的主要原因。该产品活塞杆采用300M钢材质,对氢脆比较敏感,因此在产品加工的过程中应对除氢工艺进行严格控制,以避免氢脆现象的发生。

The main landing gear is used for take-off,landing,rolling,and parking.The piston rod of the main landing gear is subjected to the pressure and impact force of the oil during compression,and the piston rod will crack and fail during use.This paper analyzes the failure of piston rod cracks.The analysis results show that the failure of the piston rod is caused by hydrogen embrittlement,and the main reason for hydrogen embrittlement is improper control of the removing hydrogen process after chrome-plating.The piston rod of this product is made of 300M steel,which is sensitive to hydrogen embrittlement.The hydrogen removal process is strictly controlled in the process of product processing to avoid the occurrence of hydrogen embrittlement.