杠杆断裂原因分析

Reason Analysis for Lever Crack

对杠杆断裂样品进行分析,结果表明:气体渗氮时产生的氢在杠杆薄弱环节聚集,形成沿晶微裂纹,使用过程中在该区域产生应力集中现象,最终导致杠杆短期断裂失效。此外,杠杆不合理的外形设计也对断裂起到促进作用。通过提高回火温度,及时使氢充分逸出,并改进杠杆的外形设计,消除氢脆。

Through the analysis of specimen for the cracked lever, the results show that hydrogen is aggregated in the weak area of lever during gas nitriding to cause the formation of microerack along the crystal, and the stress concentration is occurred in the area during using, which results in short-term fracture of lever. In addition, the illogical figure design of lever also contributes to the fracture. Hydrogen embrittlement is eliminated by increasing the tempering temperature, making hydrogen overflow fully in time, and improving the figure design of lever.