High compression performance of Cf/SiC-Al composites fabricated by CVI and vacuum pressure infiltration

The strengthening effect of aluminum (Al) alloy as the second phase matrix on Cf/SiC-Al composites was investigated, and microstructures and compression performance of the composites were characterized and tested. The results show that compressive strength and modulus of Cf/SiC-Al composites were 627?21.4 MPa and 98?2.4 GPa, respectively. Compared with Cf/SiC composites prepared by chemical vapor infiltration (CVI) process, the compressive strength increased by 34.8%, and the modulus increased by 8.9%. The introduction of Al alloy by vacuum pressure infiltration process significantly improved the ability of the composites to withstand pressure loads. However, due to the Al alloy filling in the inter-bundle pores inside Cf/SiC composites, the space for the fiber to be deformed by force was limited, and the length of the fiber extraction was shortened.

Automated summary

The study revealed that using aluminum alloy as the second phase matrix can effectively enhance the performance of Cf/SiC-Al composites, resulting in higher compressive strength and modulus for composites prepared by vacuum pressure infiltration process. However, the filling of aluminum alloy limits the space for fiber deformation, affecting the length of fiber extraction.