Acrylamide Polymerization on ceramic Powders(I) : The Process Control of Si2N4 Gelcasting by Polymerization of Acrylamicde

,; ,; ,; ,; ,; ,

J. Korean Ceram. Soc. > Volume 36(2); 1999 > Article

Journal of the Korean Ceramic Society 1999;36(2): 178.

세라믹분체 표면에서 아크릴아마이드 중합(제1보) : 아마이드 고분자중합에 의한 질화규소 겔캐스팅 공정제어

류병환, 김은영¹, 이재도

한국화학연구소 화학소재단
¹충남대학교 공업화학과

Acrylamide Polymerization on ceramic Powders(I) : The Process Control of Si2N4 Gelcasting by Polymerization of Acrylamicde

ABSTRACT

For the process control of silicon nitride gelcasting, the composition effect of acryamide system on the viscosity of slip and mechanical property of gelcast green body were investigated. The slip was prepared by ball milling of silicon nitride suspension prepared with acrylamide monomer and polyelectrolyte dispersant after premixing them by attritor. The slip mixed with initiator was vacuum deaired and cast into molds, and then polymerized. The consolidated green body was obtained by drying the gelated slip. The viscosity measument and the diametral compression test was done to evaluate the rheological behaviro of slip and mechanical property of gelcast body, respectively. Experimental results showed that the high solid loading of silicon nitride slip was obtained up to 46 vol% with a low viscosity. The mechanical property of gelcast body mainly increased with increasing the concentration of monomer. The gelcast body was machinable above the ∼3 MPa of tensile strength. The relative density of pressured-sintered body was 98.5% at 1760$^{circ}C$, 3 h.

Key words: Process control, Gelcasting, Acrylamide, Silicon nitride, Slip, Dispersion