TC6钛合金安装座荧光显示缺陷原因

Fluorescent Indication Defect Causes of TC6 Titanium Alloy Mount

某TC6钛合金安装座在航空发动机上试车后,拆机进行荧光检查,在该安装座圆弧处发现长度约4 mm的线性荧光显示。采用宏观观察、微观分析、金相检验、硬度测试、能谱分析等方法对荧光显示缺陷产生的原因进行了分析。结果表明:该安装座上的荧光显示缺陷为疲劳裂纹。安装座圆弧表面在人工砂轮打磨时完整性被破坏,形成了疲劳裂纹源,在试车过程中裂纹扩展,并与没有完全去除的锻造折叠裂纹相连接,最终形成了缺陷。

After a TC6 titanium alloy mount running on aero-engine,and it was disassembled for fluorescent inspection,a linear fluorescent indication with a length of about 4 mm was found at the arc of the mount.The causes of fluorescent indication defect were analyzed by means of macro observation,micro analysis,metallographic examination,hardness test and energy spectrum analysis.The results show that the fluorescent indication defect on the mount was a fatigue crack.The integrity of the circular arc surface of the mount was destroyed during grinding with artificial wheel grinding,and the fatigue crack source was formed.During the test run,the crack propagated and connected with the forging folding crack which was not completely removed,and finally the defect formed.