Journal of the American Ceramic Society, Vol.99, No.2, 440-444, 2016
New Approach for Macro Porous RB-SiC Derived from SiC/Novolac-type Phenolic Composite
A novel fabrication route to make macroporous silicon carbide (SiC) has been proposed in this study. The route is composed of the following two steps: the fabrication of porous -SiC/novolac-type phenolic composite using hexamethylenetetramine (HMT) as a curing/blowing agent for the novolac monomer and a conventional reaction-bonded (RB) sintering of the composite. The -SiC/novolac-type phenolic composite was carbonized at 800 degrees C for 2 h in N-2 gas and then reacted with the molten silicon at 1450 degrees C for 30 min under vacuum, resulting in the macroporous RB-SiC with an open porosity of 48% and relatively large pore size of similar to 110 m. The compressive strength of the macroporous RB-SiC was 113 MPa, which is relatively high compared to those reported for macroporous SiC of equivalent porosities and pore sizes.