（Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China）
For the research of surface damage and protection in marine, aeronautics, nuclear and other major projects, accurate phase diagram and phase transition information is the key to the efficient and reliable development of high-performance coating materials. However, coatings preparation is generally a non-equilibrium phase formation process, while their service in harsh environments results in dynamic phase transformation. Therefore, the traditional CALPHAD (CALculation of PHAse Diagrams) approach based on thermodynamic equilibrium is no longer suitable for the design of coating materials. In this work, the research progress of coating phase diagram, phase transition and its application in design of coating materials were summarized, with emphasis on the key roles of coupled CALPHAD, first-principles calculations and high-throughput experimental methods. From three aspects (materials preparation, dynamic service and database guided material development) and with typical unary, binary, ternary and multicomponent material systems as examples, the applications of metastable phase formation modeling, phase transformation simulation and phase diagram databases in the research and development of coating materials were introduced. Finally, the challenges of phase diagram, phase transformation and materials design for coatings served in harsh environments were proposed.