Solar Atmospheres Solution Ages Aluminum
Solar Atmospheres (Hermitage, Pa.) has solution aged 6061 aluminum from 0 to a T6 condition thanks to the plant’s 12-foot furnace and its advanced quenching capability. Airwolf Helicopters (Middletown, Ohio) manufactures aluminum booms for crop dusting. The 12-foot booms included smaller tubing (1 3/8 inch diameter x .058-inch wall thickness) and larger tubing that ranged from 1 5/8-2 ½ inch diameter x .058-inch wall thickness. Because of the thin wall and long length, water quenching would cause extreme distortion. Solar’s furnaces and advanced quenching capability proved to be the best alternative to attain material specifications while minimizing distortion.
To put the aluminum in solution, Solar uses a nitrogen partial pressure atmosphere in the vacuum furnace and gradually heat treats the aluminum up to 985°F. The material is held at this temperature, and then a 2-bar helium quench is performed. This brought the material to a T4 condition. While still in the furnace, age hardening is done in a nitrogen partial pressure environment. The aluminum is heated to 350°F and held at that temperature for eight hours. The tubing is quenched in nitrogen.