摘要
研究了T-250马氏体时效钢在高温缓冷条件下的冲击性能,对不同缓冷终止温度下试验钢的宏观和微观断口形貌进行观察分析,用扫描电镜观察晶界上的析出物并进行XRD物相分析。结果表明,T-250马氏体时效钢的冲击性能随缓冷终止温度的降低而下降,950℃为热脆敏感温度,此时冲击吸收功迅速下降;试验钢冲击断口的宏观和微观形貌变化规律一致,晶界析出物为Ti(C,N),随缓冷终止温度的降低在晶界上聚集,从而导致试验钢的热脆性。
Impact property of T-250 maraging steel was investigated when cooled slowly from high temperature to different final temperatures. The macro and micro fracture morphologies of the samples were observed and analyzed, and the precipitates along the grain boundary were observed by SEM and verified by XRD. The results show that the impact energy reduces with the final slow cooling temperature decreasing, and the sensitive brittle temperature of the testing steel is 950 ℃, at which the impact energy goes down severely. The macro and micro fracture morphologies have the same variation, and the precipitated phase along the grain boundary is Ti（ C, N） which gathers along the grain boundary as the final slow cooling temperature decreasing, which leads to the hot brittleness.
出处
《金属热处理》
CAS
CSCD
北大核心
2015年第2期44-48,共5页
Heat Treatment of Metals
关键词
高温缓冷
热脆
断口形貌
晶界
析出物
slow cooling from high temperature
hot brittleness
fracture morphology
grain boundary
precipitates
