减速机齿轮轴断裂分析

Analysis on Reducer Gear Shaft Breakage

针对减速机齿轮轴发生断裂现象,采用化学成分分析、断口分析、金相检验和力学性能测试对其原因进行了分析。结果表明,裂纹起源于键槽棱边应力集中处,向内疲劳扩展至断裂;棱边形状尖锐,弯曲应力集中较为严重,齿轮轴旋转时出现一定的弯矩载荷,棱边即能萌生裂纹源,引发疲劳断裂。分析结果为避免同类轴再次发生断裂提供了参考。

Aiming at the problem of breakage at reducer gear shaft, the author analyzes the cause from aspects of chemical composition analysis, fracture analysis, metallographic inspection and mechanical properties test. Analysis results show that the crack originates from the stress condensed area at keyway edge where inner fatigue extends until breakage occurs. Due to its sharp shape, the edge is seriously condensed with stress. During gear rotation, certain bending moment load generates and crack source comes into being at the edge which causes fatigue breakage. The analysis results provide reference for avoiding the breakage of the same kind of shaft.