Analysis of Ageing Precipitation Behavior of an Aluminum Alloy

Abstract:

The characterization of Al-Cu-Mg-Ag alloy with high Cu:Mg in the process of one-step ageing at the different temperatures has been studied by hardness, electrical conductivity test combining with transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results show that one endothermic and three exothermic reactions are involved in the curve of DSC experiment for a sample quenched from 520°C. Four samples were aged at the different temperatures greater or less than the peak temperatures of the four reactions. Hardness and electrical conductivity change slowly with ageing time at the low temperature and change fast at the high temperature. GP zones at {100} ɑ planes are the main precipitates in the microstructure of the sample aged at 80°C. Ω and θ phases dominant the microstructure of the samples aged at 170°C, 230°C and 280°C. In addition, the size of precipitates increases fast when the sample aged at higher temperatures.

• Periodical: Applied Mechanics and Materials (Volumes 488-489)
• Pages: 243-247
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.488-489.243
• Online since: January 2014
• Authors: Hong Xing Liu*, Jian Bo Zhang, Qi Ming Liang, Hai Jun Hu
• Keywords: Mechanical Analysis, Optimal Design, Soccer Robot

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