In this work, the effect of Sc and Mm(misch metal) on the high temperature behavior of Al-Mg alloys was observed. Hardness was increased due to appearance of fine Al₃Sc precipitates. The elongation of Al-Mg-Sc alloy at high temperature was higher th...
In this work, the effect of Sc and Mm(misch metal) on the high temperature behavior of Al-Mg alloys was observed. Hardness was increased due to appearance of fine Al₃Sc precipitates. The elongation of Al-Mg-Sc alloy at high temperature was higher than that of Al-Mg-Sc-Mm alloy because Al-Mg-Sc alloy has finer grain sizes than Al-Mg-Sc-Mm alloy. The strain rate sensitivity factor, m of AI-Mg-Sc and ACMg-Sc-Mm alloys at 475℃ and 1x10^(-2)s^(-1) were 0.33 and 0.46, respectively. The activation energies of AI-Mg-Sc and Al-Mg-Sc-Mm alloys for superplastic deformation were 133KJ/㏖ and 103KJ/㏖, respectively. The elongation of Al-Mg-Sc alloy at high temperature was decreased by the addition of Mm, but the strength at high temperatures and low strain rate was improved.