Y2O3-BN 복합체의 미세구조 및 내플라즈마 특성

Abstract

<TEX>$Y_2O_3$</TEX>-BN 세라믹 복합체를 제작하기 위해서, 분말 입도 <TEX>$3{\sim}10{\mu}m$</TEX>인 <TEX>$Y_2O_3$</TEX> 분말을 분산한 슬러리에 pH 조절제인 NaOH를 첨가하였으며 결합제로는 PVA, 가소제로는 PEG를, BN 분말과 혼합하고, 분무건조(spray drying)공정을 거쳐 <TEX>$Y_2O_3$</TEX> 혼합 분말을 제조하였다. <TEX>${\O}14mm$</TEX> 크기의 <TEX>$Y_2O_3$</TEX>-BN 시편을 성형하고, <TEX>$1550^{\circ}C$</TEX> 및 <TEX>$1600^{\circ}C$</TEX>에서 소결하여 <TEX>$Y_2O_3$</TEX>-BN 복합체를 제작하였다. BN 투입량과 소결온도의 변수에 따른 미세구조, 순도, 꺽임강도, 열팽창계수, 밀도, 체적저항, 내플라즈마 특성을 조사하였다. <TEX>$Y_2O_3$</TEX>-BN ceramic composites were fabricated from the slurries of yttria powder with average particle size of 3~10 <TEX>${\mu}m$</TEX>. The slurry was fabricated by mixing PVA binder, NaOH for Ph control, PEG, BN powder and <TEX>$Y_2O_3$</TEX> powder. The mixed <TEX>$Y_2O_3$</TEX> powders were obtained by spray drying process from the slurry. The <TEX>$Y_2O_3$</TEX>-BN composite specimen was shaped in size of <TEX>${\O}14mm$</TEX> and then sintered at <TEX>$1550^{\circ}C$</TEX> and <TEX>$1600^{\circ}C$</TEX>, respectively. The characteristics, microstructure, purities, densities, bulk resistance, thermal expansion, hardness and plasma resistance of the <TEX>$Y_2O_3$</TEX>-BN composites were investigated with the function of BN contents and sintering temperature.