一种新型Q-P-T钢的工艺与组织性能  

Processing design and microstructure and mechanical properties of a new type of Q-P-T steel

作　　者：李娜[1,2] 刘国权[1,3] 康人木[1,4] 杨云[1,3] 余慧[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]江苏省南通建工集团股份有限公司,江苏南通226000 [3]北京科技大学新金属材料国家重点实验室,北京100083 [4]四川省川威集团有限公司,四川成都610100

出　　处：《材料热处理学报》2013年第3期118-124,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金项目(51071019);国家高级技术研究发展计划项目(863计划)(2013AA031301)

摘　　要：设计和研究了一种新型高铝(1.8%Al)淬火-碳分配-回火(Q-P-T)高强钢。基于JMatPro 6.0软件和约束条件碳平衡热力学(Constrained Carbon Equilibrium,CCE)模型的模拟计算结果,制定了该钢的热处理工艺,进行了盐浴热处理和力学性能实验,并通过SEM和TEM对实验钢的组织进行了观察与分析。结果表明:Q-P-T实验钢的组织主要由板条马氏体、一定数量的富碳残留奥氏体和弥散分布的碳化物组成,其中马氏体和弥散的碳化物主要提供强化,残留奥氏体则主要起到提高塑性的作用。实验钢经Q-P-T处理后获得了高抗拉强度(1260 MPa)和塑性(18%)的良好匹配且其热处理工艺容易控制,验证了高铝钢采用Q-P-T热处理的可行性。A new type of high aluminum （1.8% A1） Q-P-T high strength steel was designed and studied. Its heat treatment process parameters were designed based on the calculation using both the JMatPro 6.0 software and the CCE （Constrained Carbon Equilibrium） model. Microstructure and mechanical properties of the steel after the Q-P-T treatment were studied by means of SEM, TEM, and tensile test. The results show that the microstructure consists of lath martensite, carbon-enriched residual austenite and dispersed carbides, where the martensite and the dispersed carbides guaranteed the strength, the retained austenite guaranteed the plasticity. The high tensile strength （trb = 1260 MPa） and the high total elongation （δ = 18% ） are obtained by easily controlled Q-P-T process, so that the feasibility of the high aluminium Q-P-T steel is proved.

关 键 词：高铝Q-P-T钢 高强度低合金钢 热处理工艺 强韧化 残留奥氏体 

分 类 号：TG142.14[一般工业技术—材料科学与工程]