固溶处理对轻质高强钢组织和力学性能的影响  

Effect of Solution Treatment on Microstructure and Mechanical Properties of Light-Weight High-Strength Steel

作　　者：霍永涛 戴伟 何燕霖[1] 李麟[1] HUO Yongtao;DAI Wei;HE Yanlin;LI Lin(School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China)

机构地区：[1]上海大学材料科学与工程学院,上海200444

出　　处：《上海金属》2022年第4期69-75,共7页Shanghai Metals

摘　　要：采用扫描电子显微镜、X射线衍射仪、透射电子显微镜等对经650~1050℃固溶处理的18Mn-7Al-0.6C(质量分数/%)轻质高强钢的微观组织进行了研究,并结合室温拉伸试验对试验钢的力学性能及瞬时应变硬化指数随真应变的变化进行了分析。结果表明:试验钢的显微组织由奥氏体和δ-铁素体组成,经650℃固溶处理后,由于两相组织变形特点存在较大差异,钢的断后伸长率较低。随着固溶温度的升高,热力学稳定的奥氏体逐渐取代了δ-铁素体,其层错能为55~60 mJ/m2。试验钢在孪晶诱发塑性和位错平面滑移效应的共同作用下可以获得较好的力学性能。Microstructure of 18Mn-7Al-0.6C(mass fraction/%)light-weight high-strength steel after solution treatment at temperatures ranging from 650 to 1050℃was investigated by using scanning electron microscope,X-ray diffractometer,and transmission electron microscope.Combined with tensile tests at room temperature,the mechanical properties of the experimental steel and the change of instantaneous strain hardening index with true strain were analyzed.The results showed that the microstructure of the experimental steel was composed of austenite andδ-ferrite,after solution treatment at 650℃,the elongation was low due to the great difference in the deformation characteristics of the two phases.As the solution temperature increased,δ-ferrite was gradually replaced by the thermodynamically stable austenite,and its stacking fault energy was from 55 to 60 mJ/m2.The experimental steel could obtain good mechanical properties by the action of both twinning-induced plasticity and dislocation plane slip.

关 键 词：轻质高强钢 Δ-铁素体 奥氏体 形变孪晶 力学性能 

分 类 号：TG142.7[一般工业技术—材料科学与工程]