镁在Al2O3／Al-Mg-Si复合材料中的作用

The Effects of Magnesium in Al2O3/Al-Mg-Si Composites

摘要:

研究了镁对Al-Mg-Si合金熔体氧化热力学与动力学的作用，以及对Al2O3／Al-Mg-Si复合材料组织与性能的作用。热力学与动力学分析表明：镁促进了Al2O3的形核和长大，Al2O3／Al复合材料的性能改善是由于尖金石（MgAl2O4）的分析所导致的组织细化。但在合金中，镁含量太高或太低都对Al2O3的形核和长大不利。

Abstract:

The effect of magnesium on thermodynamics and kinetics of oxidation of melted Al-Mg-Si alloy, the microstructure and properties of Al2O3/Al-Mg-Si composites were studied in this paper. It has been found that magnesium promotes nucleating and growing of Al2O3 in Al2O3/Al composite by analysis of thermodynamics and kinetics. The properties of Al2O3/Al composite were improved by microstructure refining due to spinel (MgAl2O4) decomposing. But too high or too low content of Mg in the alloy is disadvantageous for Al2O3 nucleating and growth.