Fabrication of the Green Body Consisting of Silicon Carbide Mixed with Carbon Powders Using Gel-casting Method

摘要

PURPOSE: Provided is a preparation method of SiC/C mold by gel casting which is characterized by adding five kinds of additives to SiC/C powder step by step. The resultant SiC/C mold has high forming density and forming strength so that it shows large and complicate shapes. CONSTITUTION: The preparation method for SiC/C mold is as follows: preparing a SiC/C slurry by adding 0.5-1.0wt.% of naphthalene sulfonic formaldehyde condensate(T-N) as a dispersant and water to SiC/C powder composed of 70-90wt.% of SiC and 10-30wt.% of C, and ball-mixing for 1hr.; adding a binder, 12-18wt.% of acrylamide (AM, C2H3CONH2), and cross-linker, 0.5-0.8wt.% of N,N-methylene bisacrylamide (MBAM, (C2H3CONH)2CH2), and ball-mixing for 24hrs.; adding a catalyst, 1.0-6.0mL/L of tertramethylethylenediamine(TEMED), and ball-mixing for 30min.; adding a reaction initiator, 0.2g/L of ammonium persulfate(APS, (NH4)2S2O8), and mixing for 5min.; removing foams; molding and polymerizing; drying.