Process model to predict yield strength of AA6063 alloy

In the present study, an attempt has been made to examine the appropriateness of the models for predicting yield strength of age hardenable 6063 Al-Mg-Si alloy. Two physical models have been considered: one is classical dislocation-particle interaction model which incorporates both cutting and by-pass mechanisms around spherical shaped precipitates; and the other is based on only dislocation by-pass of the rod shaped precipitates as per modified Orowan equation. The prediction of yield strength using these models has been compared with experimentally generated yield strength data of the selected Al-alloy subjected to different combinations of time and temperature of ageing. The microstructural variations due to ageing have been simulated using the well established thermodynamic and kinetic relationships. Comparison of the experimental and the simulated results assists to conclude that modified Orowan mechanism predicts yield strength better than that by the classical model up to the peak aged conditions. The generated results have been successfully used to develop thermal processing maps that can be considered as a convenient tool for selection of age hardening parameters to achieve any desired level of yield strength for AA6063 alloy.