高温高压下合金碳化物Fe_(3)Mo_(3)C热力学性质的第一性原理计算  

First-principles calculation of thermodynamic properties of alloy carbide Fe_(3)Mo_(3)C at high temperature and pressure

作　　者：郑鹏 侯廷平[1,2,3] 林恒福 李钰[1,2,3] 刘伍明 吴开明 ZHENG Peng;HOU Ting-Ping;LIN Heng-Fu;LI Yu;LIU Wu-Ming;WU Kai-Ming(Hubei Province Key Laboratory of Systems Science in Metallurgical Process,Wuhan 430081,China;State Key Laboratory of Refractories and Metallurgy,Wuhan 430081,China;Collaborative Innovation Center for Advanced Steels,Wuhan University of Science and Technology,Wuhan 430081,China;Institute of Physics Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]冶金工业过程系统科学湖北省重点实验室,武汉430081 [2]湖北省部共建耐火材料与冶金国家重点实验室,武汉430081 [3]武汉科技大学高性能钢铁材料及其应用省部共建协同创新中心,武汉430081 [4]中国科学院物理研究所,北京100190

出　　处：《原子与分子物理学报》2023年第3期102-108,共7页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金面上项目(12174296,61835013);国家重点研发计划(2021YFA1400900,2021YFA0718300,2021YFA1400243);湖北省重点研发计划项目(2021BAA057);2019年度湖北省高等学校优秀中青年科技创新团队(T201903);111计划项目(D18018)。

摘　　要：基于平面波赝势密度泛函理论的第一性原理与准谐德拜模型结合的方法研究了高温高压下合金碳化物Fe_(3)Mo_(3)C的热力学性质.在压强范围为0~40 GPa和温度范围为0~1200 K的条件下,Fe_(3)Mo_(3)C的体积比V/V_(0)、体弹性模量B和德拜温度θ受压强的影响比温度更大.温度一定时,体弹性模量和德拜温度随压强的增大而迅速增大.Fe_(3)Mo_(3)C的热容C_(v)、熵S以及热膨胀系数α受温度的影响较压强更大.压强一定时,材料的热容、熵以及热膨胀系数均随温度升高单调增大,其中,热容和热膨胀系数随温度先快速上升后趋于平缓,最后热容接近于Dulong-Petit极限.The thermodynamic properties of alloy carbide Fe_(3)Mo_(3)C are studied by combining density functional theory with quasi-harmonic Debye model at high temperature and high pressure.The ranges of pressure and temperature belong to 0~40 GPa and 0~1200 K,respectively.The calculated results show that the influences of pressure on volume ratio V/V_(0),bulk elastic modulus B and Debye temperatureθare greater than those of temperature.When the temperature is constant,bulk elastic modulus and Debye temperature increase rapidly with the increase of pressure.Compared with the influences of the pressure on the heat capacity C_(v),entropy S and thermal expansion coefficientα,the temperature provides higher priority.When the pressure remains constant,the three physical parameters(C_(v),S andα)all increase monotonically with temperature increasing.The heat capacity and thermal expansion coefficient increase rapidly with the temperature at first,then tend to be flat,and finally are close to the Dulong-Petit limit.

关 键 词：第一性原理 德拜模型 合金碳化物 热力学性质 

分 类 号：O65[理学—分析化学]