Synthesis of Ti₃SiC₂-based materials by reactive melt infiltration

In this paper, Ti₃SiC₂-based materials were fabricated by reactive melt infiltration (RMI), and the effect of carbon and Al on the formation of Ti₃SiC₂ was discussed. In the infiltration process of Si melt, the existence of carbon in the initial preform is beneficial to the formation of Ti₃SiC₂. Carbon can react with TiSi₂ to form new TiC with more carbon vacancies than the initial TiC, promoting the formation of TiC twins and Ti₃SiC ₂. In the infiltration process of Al-Si alloy, the existence of Al can effectively decrease the twin boundary energy of TiC grains, leading to the formation of TiC twins and nucleation of Ti₃SiC₂. There is a diffusion-competition process existing between Si and Al melts, leading to a higher Si/Al ratio in the final samples than in the Al-Si alloy. A possible formation mechanism was proposed to explain the final products.