METHOD AND APPARATUS OF FORMING A WROUGHT MATERIAL HAVING A REFINED GRAIN STRUCTURE

摘要

A method of forming a wrought material having a refined grain structure is provided. The method comprises providing a metal alloy material having a depressed solidus temperature and a low temperature eutectic phase transformation. The metal alloy material is molded and rapidly solidified to form a fine grain precursor that has fine grains surrounded by a eutectic phase with fine dendritic arm spacing. The fine grain precursor is plastic deformed at a high strain rate to cause recrystallization without substantial shear banding to form a fine grain structural wrought form. The wrought form is then thermally treated to precipitate the eutectic phase into nanometer sized dispersoids within the fine grains and grain boundaries and to define a thermally treated fine grain structure wrought form having grains finer than the fine grains and the fine dendritic arm spacing of the fine grain precursor.