Effect of Homogeneous Mixing of Sintering Additives by Coprecipitation Method on Mechanical Properties of Pressureless-Sintered <TEX>$Si_3N_4$</TEX>

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J. Korean Ceram. Soc. > Volume 30(4); 1993 > Article

Journal of the Korean Ceramic Society 1993;30(4): 265.

공침법에 의한 소결첨가제의 균일혼합이 $Si_3N_4$ 상압소결체의 기계적 특성에 미치는 영향

김지순

울산대학교 재료공학과

Effect of Homogeneous Mixing of Sintering Additives by Coprecipitation Method on Mechanical Properties of Pressureless-Sintered $Si_3N_4$

ABSTRACT

Effect of mixing homogeneity in powder mixtures of Si3N4 and sintering additive (10mol% YAG) prepared by coprecipitation on the mechanical properties of pressureless-sintered body was investigated. Sintering was performed in a graphtie furnace at 1850℃ for 0.5h under 0.15MPa N2 atmosphere using Si3N4 powder bed. Results from the measurement of Young's modulus, Vickers hardness, 4-point-bending strength, and KIC for the coprecipitation-treated (CP) and the mechanically-mixed specimens(MM) showed that a remarkable improvement in flexural strength and Weibull parameter can be achieved for the CPspecimens: (677±68MPa, 12.0) for CP samples and (539±108MPa, 5.5) for MM. Other properties were almost same irrespective of preparation methods.