Spray atomized and codeposited Al-Li base metal-matrix composites processing and properties

Spray atomization and codeposition is a solution to problems involved in the manufacturing of metal matrix composites. More efficiently than other processing methods, the proposed technique avoids detrimental chemical reactions at the metal/ceramic interface generated by the high reactivity of liquid metals. Due to shortest possible exposure time of the ceramics to the melt, the process provides optimum integrity of the interface. Thermal stability is ensured, at least for the investigated Al-2024 Li alloys, and mechanical properties are well preserved at 250°C. As spray atomization involves high quenching rates, additional benefits such as microstructural homogeneity, grain refinement and increased solid solubility of dispersoid or precipitate forming elements are expected. Codeposition yields solid deposits (or preforms) that exhibit good tensile properties, after proper densification. The reinforcement particles enhance precipitation kinetics and significantly reduce the time to attain peak-age.