A Novel Approach for Rapid Solidification Processing of High Strength PM Aluminum Alloys

Incremental spray casting has been applied to the consolidation of advanced high strength aluminum alloys requiring rapid solidification processing. The conditions for incremental spray casting are described and compared with the spray rolling process as proposed originally by A. R. E. Singer. Microstructures and tensile properties of the aluminum alloys 7075, 7091, and PM64 prepared by incremental spray casting and subsequently rolled and heat treated are presented and compared with their conventionally prepared counterparts.

This process provides a direct route from pre-alloyed melt stock to sheet bar; it is a promising alternative to conventional powder metallurgy methods for producing a dense, rapidly solidified deposit of high strength PM aluminum alloy.

At the present time the process is limited to producing deposit thicknesses of about 1 to 2 cm. Improved methods of extracting heat from the solidifying deposit are required for scaleup to thicker sections.