700MPa低合金高强钢微观组织及强化机制研究  

Study on Microstructure and Strengthening Mechanism of 700 MPa High Strength Low Alloy Steel

作　　者：杨晶晶[1] 张勇福[1] 吴润[1] 唐梦霞[1] 谭佳梅[2] 

机构地区：[1]武汉科技大学钢铁冶金与资源利用省部共建教育部重点实验室,湖北武汉430081 [2]武汉钢铁股份有限公司CSP分厂,湖北武汉430080

出　　处：《热加工工艺》2013年第19期33-35,39,共4页Hot Working Technology

摘　　要：通过对比CSP生产的Q345B低碳钢和700MPa级低合金高强钢,研究了700 MPa级低合金高强钢的强化机理。结果表明:高强钢比Q345B具有更高的抗拉强度和屈服强度。高强钢中细晶强化、固溶强化及位错强化的强化增量分别为69、36、17 MPa。析出强化主要来自于相变时或相变后从铁素体中析出的TiC,其粒子直径小于20 nm。高强钢最终有22.3%[Ti]以TiC的形式从铁素体中析出,带来屈服强度增量为117MPa。因此。Through comparing Q345B low-carbon steel and 700MPa high strength steel produced by compact strip production,the strengthening mechanism of 700MPa high strength steel was studied. The results show that 700 MPa high strength steel has higher tensile strength and yield strength than Q345B. The strength increment from grain refinement, solution and dislocation strengthening of high strength steel is 69, 36, 17MPa, respectively. The size of TiC with less than 20 nm is the main phase of precipitation hardening which precipitate in the ferrite during phase transformation. There is 22.3% [Ti] precipitating from the ferrite in the form of TiC in the high strength steel, which result in an increase of 117 MPa to the yield slrength. Consequently, the grain refinement and precipitation hardening are the dominant factors to increase the yield strength in the steels.

关 键 词：CSP技术 700MPa 级高强钢 析出硬化 强化机制 

分 类 号：TG335[金属学及工艺—金属压力加工]