Calculation and Analysis of Valence Electron Structures of the Precipitated Phases in Al-Cu Alloy

Abstract:

According to the empirical electron theory of solids and molecules, the valence electron structures of GP zone, θ″, θ′ and θ phases in Al-Cu alloys are calculated out. The results show that the number of covalent electron pairs on the strongest bond A of GP zone is greater than that of of the  matrix, i.e., the obstruction of in GP zone for dislocation movement is stronger than that of in the  matrix. Only based on the bond strength of composition atoms, it can be found, , , and  phases have strengthening effects for Al-Cu alloys. The strengthening effect of  is the strongest, and  is weaker, and  is the weakest. Compared with, the bond strength of  and  is weaker than that of . From the value of nA, it is easy to reconstruct the bonds of GP zone, , and , but is difficult to reconstruct the bonds of .

• Periodical: Advanced Materials Research (Volumes 79-82)
• Pages: 1177-1180
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.79-82.1177
• Online since: August 2009
• Authors: Wei Dong Liu, Hua Qu
• Keywords: Al-Cu Alloys, Precipitation, Valence Electron Structure (VES)

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