MarBN钢中MX和M23C6析出的热力学研究  

Thermodynamic study on precipitation of MX and MC in MarBN steel

作　　者：孙烨 杨文晟 郭汉杰[1,2] 郭靖 段生朝[1,2] SUN Ye;YANG Wensheng;GUO Hanjie;GUO Jing;DUAN Shengchao(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials,Beijing 100083,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]高端金属材料特殊熔融与制备北京市重点实验室,北京100083

出　　处：《钢铁研究学报》2021年第7期619-626,共8页Journal of Iron and Steel Research

基　　金：四川省科技计划资助项目(18SYXHZ0069)。

摘　　要：通过扫描电子显微镜观察了MarBN钢M_(23)C_(6)的分布情况;分析了MarBN钢中MX、M_(23)C_(6)主要的形核位置;计算了MarBN钢中V、Nb和Cr的碳化物和氮化物在不同温度下的实际溶度积及平衡溶度积,由此得出MarBN钢在液相、固相前沿、固相中的析出规律,并与一些学者的实验结果对比验证。结果表明:在固相中,碳氮化物的析出顺序为NbN、NbC、VN、VC、Cr_(23)C_(6),析出温度依次为1 522、1 472、1 377、1 122、1 021.7 K。另外,从热力学的角度阐明了不同正火温度下MX、M_(23)C_(6)的溶解程度;解释了学者实验观察到的"翅膀"状MX的形成过程。这为控制MarBN钢热处理过程及预测第二相析出行为提供了有效的理论依据。The distribution of M_(23)C_(6) in MarBN steel was observed by a scanning electron microscopy(SEM). The main nucleation positions of MX and M_(23)C_(6) in the steel were analyzed. The actual solubility product and equilibrium solubility product of carbides and nitrides of V, Nb, and Cr in MarBN steel at different temperatures were calculated. The precipitation rules of MarBN steel in the liquid phase, solid-liquid front, and solid-phase were obtained and compared with the experimental results of some scholars. The results show that the precipitation sequence is as follows, NbN, NbC, VN, VC, and Cr_(23)C_(6), and the precipitation temperatures are 1 522, 1 472, 1 377, 1 122, 1 021.7 K, respectively. Besides, the dissolution degree of MX and M_(23)C_(6) at different normalizing temperatures was clarified from the thermodynamic point of view, and the formation process of "wing-like" MX observed by scholars is explained. This provides an effective theoretical basis for controlling the heat treatment process and predicting the precipitation behavior of the second phase in MarBN steel.

关 键 词：MarBN钢 碳氮化物析出 热力学计算 

分 类 号：TG11.4[金属学及工艺—物理冶金]