Effects of Mg Addition with Natural Aging Time on Two-Step Aging Behavior in Al-Mg-Si Alloys.

Influence of Mg contents with the natural aging (NA) time on the two-step aging behavior in Al-Mg-Si alloys is studied. Hardness is gradually increased during NA in the 3M4S, whereas dramatic increase of hardness after NA for 3.6 ks is confirmed in the 9M4S.