Material combination conditions of the polymer infiltration and pyrolysis-melt infiltration hybrid process to make a dense and uniform matrix of SiC fiber-reinforced SiC matrix composite

In this study we investigated methods of forming matrices of SiC/SiC composite, which have recently attracted considerable attention as high temperature structural materials that can be used in airplane engines etc. We examined ways of balancing the formation of the dense, strong microstructures with the infiltration into fibrous preforms. A process in which a green body was prepared by polymer infiltration and pyrolysis (PIP) processing, using slurry containing a liquid precursor polymer and fine powders, was densified using melt infiltration (MI) processing. Promising combinations of raw materials and their ratios were selected based on past research results. The microstructures and elemental distributions obtained from those materials after the last PIP processing and after the MI processing, as well as the thermal and mechanical properties of the composites, were comparatively evaluated. Thus, favorable conditions of raw material combinations to fabricate a high-performance matrix were determined.