Al–Mg–Si合金押出材の二段時効特性

抄録

The two-step aging behaviors of various Al–Mg–Si alloy extrusions have been studied mainly by tensile testing, differential scanning calorimetric analysis (DSC) and electrical resistance measurements. The natural aging at 5°C, 20°C and 40°C for 86.4 ks has a beneficial effect on the strength after artificial aging of the low Mg₂Si containing alloys. On the other hand, the natural aging has a negative effect on the strength after artificial aging of the high Mg₂Si containing alloys. The β″ peak on the DSC curve shifts to a higher temperature with natural aging for the high Mg₂Si alloy. However, no β″ peak was found for the low Mg₂Si alloy. This suggests that there is no negative effect dominated by β″ phase for the lower Mg₂Si alloys.