| 摘要 |
The present invention relates to aluminum alloy and a manufacturing method thereof and, more specifically, to aluminum alloy under-modified by adding 0.003 to 0.01 wt% of strontium to aluminum including 6 to 8.5 wt% of silicon, 0.5 to 1.5 wt% of copper, 0.3 to 1.0 wt% of magnesium, inevitable impurities and residual aluminum, and to a method for manufacturing aluminum alloy. The method for manufacturing aluminum alloy comprises the steps of: under-modifying aluminum alloy by adding 0.003 to 0.01 wt% of strontium to aluminum including 6 to 8.5 wt% of silicon, 0.5 to 1.5 wt% of copper, 0.3 to 1.0 wt% of magnesium, inevitable impurities and residual aluminum (step 1); and conducting the solid solution treatment of the under-modified aluminum alloy in step 1 at temperatures of 520 to 540°C (step 2). The aluminum alloy according to the present invention has high strength at room temperature and high temperature by including copper and magnesium and can provide high elongation by adding strontium, which is a Si modifier, at the level of under-modification. Also, copper and magnesium-based intermetallic compounds generated during solidification are decomposed by conducting solid solution treatment and aging treatment at specific temperature and for specific time. Accordingly, solid solution to the matrix of the two alloy elements can be maximized. |
