Method and apparatus of forming a wrought material having a refined grain structure

A method of forming a wrought material comprising the steps of:

• providing a metal alloy material having a depressed solidus temperature and a low temperature eutectic phase transformation;
• at least substantial melting the metal alloy material;
• molding with high injection speed and short fill time and rapidly solidifying the metal alloy material to form a fine grain precursor having low porosity and fine grains surrounded by eutectic phase, the eutectic phase having fine dendritic arm spacing;
• imparting plastic deformation to the fine grain precursor by a high strain rate deformation strain to reduce the porosity, to avoid blistering and to cause recrystallization without substantial shear banding, thereby forming a fine grain structure wrought form, the step of imparting plastic deformation further including:
• at least one of subdividing or dissolving the eutectic phase;
• and
• precipitating a portion of the eutectic phase in situ;
• imparting at least one thermal treatment to the fine grain structural wrought form to further disperse the eutectic phase 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 form, the precipitated eutectic phase forming nanometer sized dispersoids within at least one of the fine grains and grain boundaries of the thermally treated fine grain structure wrought form.