55SiCr弹簧钢丝冷卷断裂原因分析

Cause analysis on cold roll fracture of 55SiCr spring steel wire

55SiCr弹簧钢丝在冷卷过程中发生断裂。观察断裂位置的宏观和微观形貌,并对断裂试样进行了化学成分、硬度、晶粒度以及金相组织分析。结果表明:悬架弹簧在冷卷过程中发生断裂,宏观观察断裂起源于弹簧外侧表面,弹簧试样表面存在横向擦伤,钢丝冷卷时产生应力集中是其断裂的主要原因。

55SiCr spring steel wire fractured during cold rolling process.Macroscopic and microscopic morphology of fracture location is observed,and chemical composition,hardness,grain size,and microstructure of fracture sample is analyzed.Results show that suspension spring fractured during cold rolling process.Spring fracture originates from outer surface,and there are transverse scratches on surface of spring sample.The main reason for fracture is stress concentration generated during wire cold rolling.