Method of producing superplastic alloys and superplastic alloys produced by the method

A method for producing a superplastic aluminum alloy, said method comprising:

• providing an alloy for processing, said alloy being a 6013/6111 alloy;
• solution heat treating said alloy;
• cooling the alloy to form a supersaturated solid solution;
• plastically deforming said alloy in a first deformation step sufficiently to form a high-energy defect structure, thereby forming nucleation sites useful for the subsequent nucleation of precipitates;
• aging said alloy, thereby forming precipitates at said nucleation sites;
• plastically deforming said alloy in a second deformation step to provide sufficient strain energy in said alloy to ensure recrystallization;
• and
• statically recrystallizing said alloy.

A superplastic 6xxx aluminum alloy having a maximum strain rate sensitivity of at least about 0.5 and exhibiting a maximum elongation of at least about 350%, and being produced according to a process comprising:

• providing an alloy for processing, said alloy comprising a matrix phase and at least two alloying elements, at least one of said alloying elements being, or being capable of forming, a dispersoid phase substantially insoluble in said matrix phase;
• solution heat-treating said alloy;
• cooling the alloy to form a supersaturated solid solution;
• plastically deforming said alloy in a first deformation step sufficiently to form a high-energy defect structure, thereby forming nucleation sites useful for the subsequent nucleation of precipitates;
• aging said alloy, thereby forming precipitates at said nucleation sites;
• and
• plastically deforming said alloy in a second deformation step, and statically recrystallizing said alloy, through a particle-stimulated nucleation process.