Gelcasting of SiC using epoxy resin as gel former

Epoxy resin was used as gel former in SiC gelcasting. A hardener as cross-linker causes a nucleophilic addition reaction of epoxy resin instead of free radical reaction of the acrylamide-based gel former system to avoid oxygen and mould materials (plastic and rubber) inhibition. The gelling behavior of premix solution and slurry was investigated by the change of elastic modulus (G') changing during gelling. Data show 3.4 wt% hardener in 15 wt% epoxy resin solution to be the optimized content to obtain gel with high-G'. Both the polymerization process and the gelation process depend greatly on temperature, which is beneficial for mixing and casting. Green bodies fabricated with epoxy resin show that rubber do not inhibit in the process. (C) 2008 Elsevier Ltd and Techna Group S.r.l. All rights reserved.