A Study on Dispersion and Sintering of $Si_3$$N_4$ Powder

$Si_3$$N_4$ 분말의 분산과 소결에 관한 연구

The objective of this study is to investigate the effect of dispersion of silicon nitride powder with 5wt% $A1_2$$O_3$ and 5wt% $Y_2$$O_3$ on the microstructure of a sintered body. $Si_3$$N_4$ powder was dispered in a distilled water with varing pH.Zeta potential was measured and the dispersion states were directly observed by SEM. Green bodies were obtained by slip-casting and fired at $1750^{\circ}C$ for 1 hr. Microstructures of fired specimens were observed by SEM. The result were that the specimen prepared from the dispersions with pH 5 and 10 showed the best densification.

$Si_3$$N_4$$-5^w$/$oA1_2$$O_3$$-5^w$/$oY_2$$O_3$ 분말의 분산이 소성후 미세구조에 미치는 영향을 조사하였다. 분산은 pH를 변화시켜 가면서 행하였고, 분산상태를 직접 전자 현미경으로 관찰 하였다. 각시편을 $1750^{\circ}C$에서 1시간 소성하여 치밀도를 조사하였으며 그결과 pH5, pH10에서 분산시킨 분말이 가장 치밀하게 소결되었다.