공학
한국표면공학회지 (44권4호 125-130)
Oxidation of Hot Pressed Cr2AlC Compounds at 900-1200℃ for Up to 50 Hours in Air
열간 압축법으로 제조된 Cr2AlC 화합물의 900-1200℃, 50시간 동안의 대기중 산화
이동복;
Lee, Dong-Bok;
성균관대학교 신소재공학과;
School of Advanced Materials Science & Engineering, Sungkyunkwan University;
DOI : 10.5695/JKISE.2011.44.4.125
Abstract
$Cr_2AlC$ compounds were synthesized by hot pressing, and oxidized between 900 and $1200^{circ}C$ in air for up to 50 hours. They oxidized to a thin $Al_2O_3$ layer containing a small amount of $Cr_2O_3$with the liberation of carbon as CO or $CO_2$ gases. The consumption of Al to form the $Al_2O_3$ layer led to the depletion of Al and enrichment of Cr just below the $Al_2O_3$ layer, resulting in the formation of an underlying $Cr_7C_3$ layer. As the oxidation temperature and time increased, the $Cr_7C_3$ oxide layer and the underlying $Cr_7C_3$ layer thickened. The oxidation resistance of $Cr_2AlC$ was generally good due to the formation of the $Al_2O_3$ barrier layer.
Keywords
Chromium;Aluminum;Carbon;Carbide;Oxidation;