摘要
本文通过热疲劳试验,复膜电子金相、扫描断口分析等方法研究了热处理对3Cr2W8V钢热疲劳性能的影响。结果表明:不同热处理状态的钢在热疲劳过程中均有循环软化效应;热疲劳抗力主要受钢的强度及热循环稳定性所控制;热疲劳断口兼有疲劳损伤和氧化腐蚀特征;热疲劳裂纹以沿晶楔入为源,按穿晶——沿晶混合方式扩展。
The effects of heat treatment regime on the thermal stress fatigue properties of 3Cr2w8v steel are investigated by thermal fatigue test,replicas electron metallograph and scanning fracture microanalysis. It showsthat there is the cycle soften effect during thermal fatigue processes ofthe steel in different heat treating conditions. Thermal fatigue resistanceis primarily dependent on the strength and thermal cycle stability of thesteel, while thermal fatigue fracture is characterized by both fatiguedamage and oxidational corrosion, and the thermal fatigue crack is initiatedin an intercrystalline wedge mode and propagated predominantly in themixed transgranular-intercrystalline mode,
