溶质元素在含Nb海工钢中析出行为的热力学研究  

Study on Thermodynamics for Precipitation Behaviors of Solute Elements in Marine Steels Containing Nb Element

作　　者：李天怡 刘文月 安涛 王超逸 臧岩 任毅 LI Tianyi;LIU Wenyue;AN Tao;WANG Chaoyi;ZANG Yan;REN Yi(State Key Laboratory of Metal Materials for Marine Equipment and Application,Anshan 114009,Liaoning,China;Ansteel Beijing Research Institute Co.,Ltd.,Beijing 102200,China)

机构地区：[1]海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114009 [2]鞍钢集团北京研究院有限公司,北京102200

出　　处：《鞍钢技术》2024年第6期7-16,共10页Angang Technology

摘　　要：采用ThermoCalc软件计算了超高强含Nb海工钢的相转变规律和第二相粒子析出规律,并将计算结果与实验结果进行对比。计算结果表明,在平衡状态下,该材料基体为铁素体相,含有的析出相主要包括Nb(C,N)相(FCC-A1#2)、BN相(BN-B4),富Mo相(HCP-A3#2)、富Cu相(FCC-A1#3)和碳化物相(M23C6-D84)。Nb(C,N)相在1171.5℃开始析出,在800℃时的析出量为0.056%,提高C、Nb元素含量会显著促进Nb(C,N)相的析出;富Mo相在700.4℃开始析出,在400℃时的析出量为0.34%;富Cu相在675.8℃开始析出,在400℃时的析出量为0.88%;碳化物相在647.7℃开始析出,在400℃时的析出量为0.9%。通过与实验结果对比可知,调质态实验钢在室温时组织由回火马氏体(BCC相)组成。在TEM下,仅观察到Nb(C,N)相,未发现BN相、富Mo相、富Cu相和碳化物相。The phase transformation behaviors and precipitation behaviors of the second phase particles of ultra-high strength Nb-containing marine steels were calculated by using the ThermoCalc software,and then the calculated results were compared with the experimental results.The calculated results showed that the matrix of this material was the ferrite phase in the balanced state,while the main precipitated phases included Nb(C,N)(FCC-A1#2),Boron nitrides(BN-B4),Mo-enriched(HCP-A3#2),Copper-enriched(FCC-A1#3)and Carbides(M23C6-D84).Among them,the Nb(C,N)phase began to precipitate at 1171.5℃,whose precipitation amount was 0.056%at 800℃.So if increasing content of both C element and Nb element would significantly promote the precipitation of the Nb(C,N).Secondly,the Mo-enriched phase began to precipitate at 700.4℃,whose precipitation amount was 0.34%at 400℃.Then,the Copper-enriched phase began to precipitate at 675.8℃,whose precipitation amount was 0.88%at 400℃.Lastly,the Carbide phase began to precipitate at 647.7℃,whose precipitation amount was 0.9%at 400℃.Therefore,it could be clear by comparing to the experimental results that the tempered experimental steel was consisted of tempered martensite(BCC phase)at room temperature.Under TEM,only the Nb(C,N)phase was observed,and other phases such as Boron nitride phase,Mo-enriched phase,Copper-enriched phase and Carbide phase were not found.

关 键 词：超高强海工钢 相转变 第二相粒子析出 

分 类 号：TG1[金属学及工艺—金属学] TP391[自动化与计算机技术—计算机应用技术]