Al₃Fe价电子结构及其对Al-Fe合金性能的影响

来源期刊：有色金属2011年第1期

论文作者：陈超 刘伟东 王鑫鑫

文章页码：1 - 4

关键词：金属材料； Al₃Fe； 价电子结构； 力学性能

Key words：metal material； Al₃Fe； valence electron structure； mechanical property

摘    要：基于EET理论计算并分析Al₃Fe的价电子结构与合金第二相强化、高温稳定性、范性的关系。结果表明,Al₃Fe最强共价键(n₁^Al₃Fe=1.0834)键合强度远大于γ-Mg₁₇Al₁₂(n₁^{γ-Mg₁₇Al₁₂}=0.3455)和Mg₂Si(n₁^Mg₂Si=0.3241)的键合强度,有利于合金强度的提高。Al₃Fe的成键能力F_v^Al₃Fe(729.87)远大于γ-Mg₁₇Al₁₂(F_v^{γ-Mg₁₇Al₁₂}=44.22)和Mg₂Si(F_v^Mg₂Si=42.76)的成键能力,有利于合金稳定性的增强。Al₃Fe的晶格电子密度ρ₁^Al₃Fe(8.6357%)小于α-Al(ρ₁^α-Al=15.6808)与Mg2Si(ρ₁^Mg₂Si=21.6478)的晶格电子密度,Al₃Fe晶胞中强、弱键分布n_α不均,不利于合金的范性。

Abstract: Based on the empirical electron theory of solids and molecules (EET),the valence electron structure of Al₃Fe phase in heat-resisting Al-Fe alloys is calculated,and the relations of the valence electron structure to the alloy second-phase strengthen,high temperature stability,toughness and ductility are systematically expressed.Calculation results indicate that the valence electron pairs on the strongest bond of Al₃Fe(n₁^Al₃Fe=1.0834) is far greater than the strongest bond of γ-Mg₁₇Al₁₂(n₁^{γ-Mg₁₇Al₁₂}=0.3455) and Mg₂Si(n₁^Mg₂Si=0.3241) which are mostly strengthen phase in traditional heat-resisting aluminum alloys,therefore Al₃Fe enormously enhanced the alloy strength.Comparing the bond-forming ability F_v ^Al₃Fe of Al₃Fe(F_v^Al₃Fe=729.87146) with the Fv value of γ-Mg₁₇Al₁₂(F_v^{γ-Mg₁₇Al₁₂}=44.22)and Mg₂Si(F_v^Mg₂Si=42.7649),it can be found that Al₃Fe is of benefit to improves the high temperature performance of Al-Fe alloys.The lattice electron density of Al₃Fe(ρ₁^Al₃Fe=8.6357%) is smaller than that of α-Al(ρ₁^α-Al=15.6808%) and Mg₂Si(ρ₁^Mg₂Si=21.6478%),and the space distribution of covalent electron pairs nα on the bonds in Al₃Fe is not uniform,these are not of benefit to improves plasticity of Al-Fe alloys.