摘要
研究了正火冷却速度对2.25Cr-1Mo钢组织转变与力学性能的影响。通过设置4种正火冷却速度,结合力学性能检测、OM、SEM等显微分析方法进行研究,并通过铁素体含量定量分析论述了2.25Cr-1Mo钢组织与性能的关系。研究结果发现,随着正火冷却速度减慢,组织中铁素体含量增加,强度与冲击吸收能量均逐渐下降。铁素体含量对力学性能影响显著,铁素体含量<36.7%时,力学性能下降幅度较小;铁素体含量>80.1%时,力学性能下降显著。铁素体能影响2.25Cr-1Mo钢抗裂纹扩展能力,大面积铁素体相,一方面降低基体强度,减小裂纹扩展阻力,另一方面在晶界形成粗大网状碳化物,导致强度与冲击韧性明显下降。
Effect of normalizing cooling rate on microstructure transformation and mechanical properties of 2.25Cr-1Mo steel was studied by means of mechanical properties testing,OM and SEM for four different normalizing cooling rate samples.And the relationship between microstructure and properties of 2.25Cr-1Mo steel was discussed with quantitative analysis of ferrite content.The results show that as the normalizing cooling rate decreases,the ferrite content in the structure increases,and the strength and impact absorbed energy gradually decrease.The ferrite content has a significant effect on mechanical properties.When the ferrite content is lower than 36.7%,the mechanical properties decrease slightly.When the ferrite content is more than 80.1%,the mechanical properties decrease significantly.Ferrite has an effect on the crack propagation resistance of 2.25Cr-1Mo steel,and the massive ferrite phase can both reduces the strength of the matrix and the crack propagation resistance.On the other hand,the coarse carbides network formed at grain boundaries results in strength and impact toughness decline significantly.
作者
韩少强
赵吉庆
万润东
杨钢
Han Shaoqiang;Zhao Jiqing;Wan Rundong;Yang Gang(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China;Institute for Special Steel,Center Iron and Steel Research Institute,Beijing 100081,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第12期94-100,共7页
Heat Treatment of Metals
基金
国家重点研发计划(2016YFB0300203)
