Microstructure and ablation behavior of Zr-Ti-Si-C multiphase coating fabricated by solid solution and in-situ reaction

The Zr-Ti-Si-C solid solution coatings were fabricated by solid solution and in-situ reaction methods, and effects of TiC on the microstructure and phase evolution, and ablation behavior of Zr-Ti-Si-C solid solution coatings were investigated. Results show that TiC was reacted with zirconium or silicon compounds to generate even-distributed ternary ZrxTi1−xC and quaternary (TixZr1−x)3SiC2 solid solution. The solid solution structure decreases the active oxidation of Si source, and reduces the depletion and evaporation of SiO2, forming a strengthened ZrO2-ZrTiO4-TiO2-SiO2 oxides layer with low oxygen diffusion coefficient, thereby enhancing the ablative property of the Zr-Ti-Si-C solid solution coatings. •The (TixZr1−x)3SiC2 phase is generated by solid solution and in-situ reaction to reinforce the UHTC coating.•The solid solution structure can densify and homogenize phases distribution of coating.•The (TixZr1−x)3SiC2 reduces the active oxidation of Si source comparing to SiC.•A strengthened ZrO2-ZrTiO4-TiO2-SiO2 layer contributes to the excellent ablation resistance of coating.•The added TiC plays a positive joint function on the long-term anti-ablation property of coating.