Al-Cu合金亚稳相的价电子结构分析

Calculation on Valence Electron Structures of Metastable Phase in Al-Cu Alloy

应用固体电子理论 (EET) ,对Al Cu合金时效析出的若干亚稳相的价电子结构进行计算。结果表明 ,在时效初期 ,θ″相中Cu原子处于第七杂阶 ,比金属Cu的原子杂阶低 ,而最靠近Cu原子的Al原子则处于第五杂阶 ;由θ″相溶解形成相θ′时 ,Al原子处于第四杂阶 ,而Cu原子状态发生较大变化 ,从基体的第九杂阶上升到第十三杂阶 ,使得Cu原子的共价电子数有较大幅度的提高 ,因此形成的θ′亚稳相的最强共价键较θ″亚稳相的要强 1倍 。

Based on to 'Empirical Electron Theory in solid and molecules' (EET), the valence electron structures of some metastable precipitations of Al Cu alloy in aging were calculated. The results show that during the early ageing, Cu atoms in θ″ phase are at ninth hybrid state which is at lower state than that in copper metal, while Al atoms which are nearest close to Cu atoms in θ″ phase are at the fifth hybrid state. When the θ″ phase dissolved and formed the θ′ phase, the Al atom in θ′ phase is at the fourth hybrid state and the state of Cu atom is enhanced from ninth′ up to thirteenth hybrid state which cause the covalence electronic numbers increase greatly in Cu atoms, so the covalence bond in θ′ phase is much stronger than that in θ″ phase. These can be used to explain the thermal stablility of these metastable precipitations in ageing on the valence electron structure levels.