重型汽车变速箱六档齿轮断裂失效分析

Fracture Failure Analysis of the Six-speed Gear on Heavy-duty Gearbox

利用断口宏观形貌观察、化学成分分析、显微组织分析和力学性能测试等方法,对重型变速箱六档齿轮断裂失效原因进行分析。结果表明该变速箱齿轮失效的主要原因是齿轮工作服役条件恶劣,轮齿表面碳浓度偏低造成齿轮抗接触疲劳强度不足,以及超负荷脉动冲击载荷等。最后提出了措施建议。

The reason of fracture failure of six-speed gear on heavy-duty gearbox was analyzed by fracture macro-morphology observation, chemical composition analysis, microstructure analysis, and mechanical property test etc. The result showed that the main reasons of the failure was the service conditions of gear so bad and the lower carbon concentration in gear surface which resulted in the gear anti-contact fatigue strength inadequate, and overload pulsating impact load to cause failure. We proposed finally prevention recommendations.