Methods of improving hot working productivity and corrosion resistance in aa7000series aluminum alloys and products therefrom

摘要

Methods of improving the corrosion resistance and hot working productivity of AA7000 series aluminum alloys include, in one mode, the steps of treating a stock material to form a globular microstructure, preferably by a thermal conversion treatment, and subsequently hot working the treated stock material, quenching it and aging it. The globular microstructure permits increasing the hot working rate to attain T6 properties using only a T5 temper practice and without adverse effect on the surface of the hot worked product as a result of the increased hot working rate. Consequently, an acceptable product is made at a significantly lower cost due to the increased hot working rates and fewer processing steps. The method also improves the corrosion resistance, particularly exfoliation corrosion resistance, of the product such that corrosion resistance generally attainable using only a T7 temper practice is achieved using only a T5 temper practice.