摩托车链轮裂纹原因分析与对策研究

某款125型摩托车大链轮出现多处裂纹，经检查主要是在高频淬火工序后出现。经对生产工艺的跟踪调查、裂纹件形貌分析和对故障零件的？台金分析发现，链轮结构、机加工应力和表面粗糙度等综合作用均是导致高频淬火裂纹的主要原因，据此制定了相关的改进措施，消除机加工应力和提高表面粗糙度可以杜绝或大大减少高频淬火裂纹，经初步验证，满足生产需要。

The Cause of Generating Cracks with Motorcycle Chain Wheels and the Countermeasures

Cracks are found with the big chain wheel of one of 125 type motorcycles. Checks show that the crack occurs after the high-frequency quenching. It is found that after the track-while-investigation, analysis of the shape of the cracked parts and metallurgical study of the faulty components, the composition of the chain wheel structure, machining stress and surface roughness is the main cause of leading to high-frequency cracks. From this relative measures have been taken for eliminating the machining stress and improving the surface roughness to stop or dismiss greatly the high-frequency cracks. Tests show that the measures meet the requirement of production.