摘要
为实现C-HRA-5含Nb奥氏体耐热钢冶炼过程气相氮合金化精确控制,进行了0.033~0.1 MPa氮气压力和1 793~1 853 K下的气相渗氮实验,建立了含Nb耐热钢的氮溶解度模型和气相渗氮动力学模型。结果表明:通过考虑Cr、Ni与Nb对氮活度相互作用系数,含Nb奥氏体耐热钢的氮溶解度模型计算结果和实测值吻合良好,氮溶解度随冶炼温度升高而减小,随氮气压力增大而增大且符合Sieverts定律。气相-钢液间的渗氮动力学过程主要受界面化学反应速率控制,氮溶解反应速率常数随温度升高而增大,氮气压力则对其无明显影响,C-HRA-5钢的氮溶解反应速率常数可表示为lgk=2.1-7 889/T cm/(%·s)。
To achieve accurate control of nitrogen gas alloying in C-HRA-5 austenitic heat-resistant steel containing Nb during melting process, gas-nitriding experiments were carried out under nitrogen pressure of 0.033-0.1 MPa and 1 793-1 853 K. The nitrogen solubility model and gas-nitriding kinetic model of the heat resistant steel containing Nb were established. The results show that: by applying the interaction coefficients of Cr, Ni and Nb on nitrogen activity, the calculated values of nitrogen solubility model of Nb-containing austenitic heat-resistant steel are in good agreement with the measured values;the nitrogen solubility decreases with the increase of temperature and increases with the increase of nitrogen pressure which conforms to the Sieverts’ law. The nitriding kinetic between gas phase and molten steel is mainly controlled by interfacial chemical reaction rate. The rate constant of nitrogen dissolution reaction increases with the increase of temperature, but the nitrogen pressure had no obvious effect on it. The rate constant of nitrogen dissolution reaction of C-HRA-5 steel can be expressed as lgk=2.1-7 889/T cm/(%·s).
作者
李旭泽
李花兵
杨守星
冯浩
姜周华
徐芳泓
LI Xuze;LI Huabing;YANG Shouxing;FENG Hao;JIANG Zhouhua;XU Fanghong(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China;Technology Center,Shanxi Taiyuan Stainless Steel Co.,Ltd.,Taiyuan 030003,Shanxi,China)
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2021年第8期709-717,共9页
Journal of Iron and Steel Research
基金
山西省科技重大专项资助项目(20181101014)
国家自然科学基金资助项目(U1960203/51774074/52004060)
博士后创新人才支持计划资助项目(BX20200076)。
关键词
奥氏体耐热钢
铌
氮溶解度
渗氮动力学
austenitic heat resistant steel
niobium
nitrogen solubility
gas-nitriding kinetics
