Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (45권4호 155-161)

Effect of CaO and Hot Rolling on the High Temperature Oxidation of Magnesium Alloys

CaO 첨가와 열간압연이 마그네슘 합금의 고온산화에 미치는 영향

;;원성빈;이동복;
Xu, Chunyu;Trung, Trinh Van;Won, Sung-Bin;Lee, Dong-Bok;

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

DOI : 10.5695/JKISE.2012.45.4.155

Abstract

Magnesium alloys of AZ31, AZ31 + (0.5, 1, 1.5)wt.% CaO were cast, hot rolled, and oxidized between 450 and $650^{circ}C$ in atmospheric air. The added CaO enabled to cast the AZ31 alloy in air. It decomposed and precipitated along the grain boundaries of the AZ31 alloy as $Al_2Ca$. The more the amount of CaO was, the more $Al_2Ca$ formed. The oxidation limit was about $450^{circ}C$ for the AZ31 alloy. But, It increased to $650^{circ}C$ in the CaO-added alloys. Hot rolling destroyed the precipitates that formed along the grain boundaries of the AZ31 alloy. During oxidation, MgO oxide scales that incorporated CaO formed at the outer surface of the formed oxide layer.

Keywords

Magnesium alloys;AZ31;CaO;Oxidation;