High Temperature and High Pressure Phase Diagram Modelling Based on CALPHAD

Author of the article:WANG Puziyu 1 , HUANG Yongxing 1 , GAO Xingyu 2 , CHONG Xiaoyu 3 , SONG Haifeng 2

Author's Workplace：1. Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China; 2. Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China; 3. National and Local Joint Engineering Laboratory for Advanced Solidification Forming and Equipment for Metals, Kunming University of Science and Technology, Kunming 650000, China

Key Words： thermodynamics; CALPHAD; temperature-pressure phase diagram; molar volume

Abstract：High temperature and high pressure phase diagrams have a very important position and application value in
physical chemistry, mineralogy, earth science and material science under extreme conditions. Calculation of phase diagram
(CALPHAD) method is the main method to establish temperature-pressure thermodynamic phase diagram and
thermodynamic database, which can calculate the phase balance of the material system, the phase fraction and phase
composition of the component phase and thermodynamic properties, to a certain extent solving the difficulty of establishing
a high temperature and high pressure phase diagram in a single experiment. This paper introduces the current high
temperature and high pressure phase diagram modelling method based on CALPHAD in detail, and summarizes the current
problems and future research directions, laying a foundation for material design and performance evaluation under extreme
conditions.