Influence of quenching rate on microstructure and dimensional stability of Al-Cu-Mg-Si alloy

With the development of precision instrument in space industry fields, increasing attention has been devoted to improve the dimensional stability of structural materials. In this study, the influence of quenching rate on microstructure, residual stress and dimensional stability of Al-Cu-Mg-Si alloy was studied. The results showed that boil water quenching resulted in very low residual stress but unsatisfactory mechanical properties. In contrast, low residual stress and good mechanical property were achieved by quenching the sample into 80 degrees C water. Residual stress has a significant influence on the thermal dimensional stability. The thermal dimensional stability of sample quenched in 80 degrees C water is better than that of sample quenched in 20 degrees C water due to lower residual stress in 80 degrees C water-quenched sample.