Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (46권2호 80-86)

Effect of CaO Addition on the High-temperature Oxidation of AZ31 Magnesium Alloys

AZ31 마그네슘 합금의 고온산화에 미치는 CaO 첨가 영향

원성빈;이동복;
Won, Sung Bin;Lee, Dong Bok;

성균관대학교 신소재공학과;
School of Advanced Materials Science and Engineering, Sungkyunkwan University;

DOI : 10.5695/JKISE.2013.46.2.080

Abstract

Magnesium alloys of AZ31 containing (0.5, 1, 1.5) wt.% of initially added CaO particles were cast in air, and their oxidation behavior was studied at $450-650^{circ}C$ in air. The initially added CaO particles either decomposed to dissolve in the ${alpha}$-Mg matrix or precipitated as $Al_2Ca$ along the grain boundaries of the matrix during casting. The ignition temperatures were $565.4^{circ}C$ for AZ31, $608.6^{circ}C$ for AZ31+0.5 wt.%CaO, and $689.7^{circ}C$ for AZ31+1 wt.%CaO. No ignition occurred for AZ31+1.5 wt.%CaO up to $700^{circ}C$, displaying good oxidation resistance. The CaO-rich oxide scales that formed on the surface of the AZ31+(0.5, 1, 1.5) wt.%CaO alloys improved the oxidation resistance of AZ31 alloys.

Keywords

Magnesium alloys;AZ31;CaO;Oxidation;