3XX ALUMINUM CASTING ALLOYS, AND METHODS FOR MAKING THE SAME
New 3xx aluminum casting alloys are disclosed. The aluminum casting alloys generally include from 6.5 to 11.0 wt. % Si, from 0.20 to 0.80 wt. % Mg, from 0.05 to 0.50 wt. % Cu, from 0.10 to 0.80 wt. % Mn, from 0.005 to 0.05 wt. % Sr, up to 0.25 wt. % Ti, up to 0.30 wt. % Fe, and up to 0.20 wt. % Zn, the balance being aluminum and impurities.
1 . A method, comprising:
(a) shape casting a 3 xx aluminum casting alloy into a shape cast product, wherein the 3 xx aluminum casting alloy comprises:
6.5-11.0 wt. % Si;
0.20-0.80 wt. % Mg;
0.05-0.50 wt. % Cu;
0.10-0.80 wt. % Mn;
0.005-0.050 wt. % Sr;
up to 0.25 wt. % Ti;
up to 0.30 wt. % Fe; and
up to 0.20 wt. % Zn;
the balance being aluminum (Al) and impurities, wherein the 3 xx aluminum casting alloy includes not greater than 0.10 wt. % of any one impurity, and wherein the 3 xx aluminum casting alloy includes not greater than 0.35 wt. %, in total, of the impurities,
wherein the shape casting step is selected from the group consisting of: high pressure die casting, gravity permanent mold casting, semi-permanent mold casting, squeeze casting, sand mold casting, centrifugal casting, and ablation casting;
(b) optionally machining the shape cast product;
(c) tempering the shape cast product, wherein, due to the tempering, the shape cast product is in a T temper.
2 . The method of claim 1 , wherein the T temper is selected from the group consisting of: T4, T5, T6, and T7 tempers.
3 . The method of claim 1 , wherein the shape cast product is an automotive product.