摘要
某液压系统进行地面开车试验约2 h时发现钛合金直角接头喷油现象,后更换另一件直角接头继续工作约3 h,在同样位置也发生开裂喷油现象。通过断口宏微观观察、能谱分析、金相检查和硬度测试,确定了直角接头的开裂性质和原因。结果表明:直角接头开裂性质为疲劳开裂;开裂原因主要与接头承受了较大应力和源区存在较厚的富氧α层有关;建议在彻底去除富氧α层的前提下,适当增加结构的设计裕度。
Titanium alloy right-angle joints in a hydraulic pressure system cracked during testing.In order to find out the cracking mode and cause,macro and micro observation on the fracture surface,energy spectrum analysis,metallurgical structure examination and hardness testing were carried out.The results show that the cracking mode is fatigue crack.The cracking is mainly related to the greater stress and the thicker oxygen-rich α layer.It is proposed that the oxygen-rich α layer be cleared and the structural margin be enlarged.
出处
《失效分析与预防》
2011年第3期178-181,198,共5页
Failure Analysis and Prevention
关键词
钛合金
直角接头
富氧α层
疲劳开裂
titanium alloy
right-angle joint
oxygen-rich α layer
fatigue cracking
