WEB Phase Content Prediction in Multi-element Polymer-derived Ceramics
In this study, nickel, molybdenum, zirconium, and cobalt were added into amorphous SiOC systems. Different ceramic phases formed from various transition metals and the SiOC matrix. CoSix/SiOC, MoCx/SiOC, and Ni/SiOC ceramic composites were obtained at 1100°C, whereas ZrOx/SiOC was formed upon pyrolysis at 1400°C. Four different types of models were established based on their phase regions (SiC-SiO2-C-CoSix, SiC-SiO2-C-MoCx, SiC-SiO2-C-ZrOx, and SiC-SiO2- C-Ni) in order to analyze the fundamental processes such as driving force for crystallization and phase fractions at different pyrolysis temperatures for the multi-element polymer derived ceramics, based on the Gibbs free energy minimization method. Thermodynamic calculation further revealed the energetics with respect to 3D quaternary phase diagram and provided guidance to the synthesis of metal-containing PDCs with desired phase contents upon ceramization of the metal-modified polymer precursors.