Preparation of Zirconium Carbide Powders from <TEX>$ZrCl_4$</TEX>-Mg-C System

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J. Korean Ceram. Soc. > Volume 28(4); 1991 > Article

Journal of the Korean Ceramic Society 1991;28(4): 315.

$ZrCl_4$-Mg-C 계 반응에 의한 탄화지르코늄(ZrC) 분체의 합성

김원영, 김성현, 장윤식, 박홍채, 오기동

부산대학교 무기재료공학과

Preparation of Zirconium Carbide Powders from $ZrCl_4$-Mg-C System

ABSTRACT

The preparation of zirconium carbide powders by the halogenide process of ZrCl4-C-Mg system (1:1:2, molar ratio) was studied between 300。 and 120$0^{circ}C$ under Ar gas flow (200 mι/min). The formation mechanism and kinetics of zirconium carbide and characteristics of the synthesized powder were examined by TG-DTA, XRD, SEM and PSA. 1) The formation mechanism of zirconium carbide were as follows, above 30$0^{circ}C$ ZrCl4(S)+Mg(s)longrightarrowZrCl2(s)+MgCl2(s) above 40$0^{circ}C$ ZrCl2(S)+Mg(s)longrightarrowZr(s)+MgCl2(s) above 50$0^{circ}C$ Zr(s)+C(s)longrightarrowZrC(s) 2) The apparent activation energy of the reduction-carbonization at temperature of 800$^{circ}$to 100$0^{circ}C$ was 11.9 kcal/mol. 3) The lattice parameter and the crystallite size of ZrC which was produced from the mixture powder of ZrCl4, C and Mg (1:1:2, molar ratio) at 100$0^{circ}C$ for 1 h were 4.700A and 180A, respectively. 4) The powders obtained from the mixture powder of ZrCl4, C and Mg(1:1:2, molar ratio) at 100$0^{circ}C$ for 1 h were agglomerate with the average size of about 13${mu}{textrm}{m}$ in SEM micrograph.