Influence of Ca addition on valence electron structure of Mg₁₇Al₁₂

来源期刊：中国有色金属学报(英文版)2003年第6期

论文作者：杜温文 孙扬善 闵学刚 薛烽 武登云

文章页码：1274 - 1279

Key words：magnesium alloy; Mg₁₇Al₁₂; calcium; valence electron structure

Abstract: The alloy AZ91 containing calcium was prepared under protection of a mixed gas atmosphere of SF₆(1%, volume fraction) and CO₂. The added calcium mainly dissolves into the Mg₁₇Al₁₂ phase in the alloy and increases its melting point and the thermal stability. The empirical electron theory (EET) of solid and molecules was used to calculate the valence electron structures (VES) of Mg₁₇Al₁₂ phase with different amounts of calcium additions. The theoretical calculations indicate that calcium dissolved in Mg₁₇Al₁₂ phase increases the strengths of atomic bonds that control the thermal stability of Mg₁₇Al₁₂ phase, and also makes the distribution of valence electrons on the dominant bond network as well as in the whole unit cell of Mg₁₇Al₁₂ more uniform, which are consistent with the experimental results.