Fabrication and Properties of Porous Carbon Preforms for Making Reaction Formed SiC

摘要

This paper describes a proper low cost way to fabricate defect-free porous carbon preforms with interconnect pore structure for making reaction formed SiC (RFSC). Taking charcoal, poplar powder, camphene and polymer dispersant together, making slurries by milling under 55°C for several hours, controlling the content of charcoal and poplar powder, after casting, sublimating and carbonizing, the porous carbon performs with a series density (0.66 g/cm~3-0.78 g/cm~3) and porosity (62.9 vol.%-68.6 vol.%) were prepared; through the Si infiltrating process under a vacuum condition (~5.0 Pa) at 1500°C for about 0.5 hour, the RFSCs with fine mechanic performance were fabricated, one RFSC sample has the density, Weibull modulus, and the max three points flexural strength is 2.91 g/cm~3, 9.5 and 505.0 MPa respectively.