某型号风机在运转过程中,其偏航驱动中的第5级行星架发生开裂。采用宏观观察、化学成分分析、扫描电镜和能谱分析、力学性能测试、硬度测试、金相检验等方法对其断裂原因进行分析。结果表明:行星架的冲击吸收能量低,抗冲击能力差,在发生被动偏航滑移时,其承受了较大的冲击载荷,在应力最大处产生裂纹,裂纹在较短时间内快速扩展,最终导致行星架发生脆性断裂。

During the operation of a certain type of fan, the fifth stage planet carrier in its yaw drive cracked. The fracture reasons were analyzed by means of macroscopic observation, chemical composition analysis, scanning electron microscopy and energy spectrum analysis, mechanical property test, hardness test and metallographic examination. The results show that the impact absorption energy of the planet carrier was low, and the impact resistance was poor. When the passive yaw slip occurred, it beared a large impact load, and cracks were generated at the maximum stress. The cracks expanded rapidly in a short time, which eventually led to brittle fracture of the planet carrier.