R. Srinivasan, Wright State University, Dayton, OH; P. Chaudhury, General Dynamics-Ordnance and Tactical Systems, Garland, TX
Severe plastic deformation (SPD) to large strains can lead to considerable refinement of the grain size of a metal. The ultrafine gain material thus produced exhibits superplastic like behavior, leading to the potential for high hot formability. In this study, fine-grained aluminum alloy 6061 with square cross-sections of 50 mm (2 inches) and 100 mm (4 inches) was produced by severe plastic deformation. The microstructure was characterized using optical and transmission electron microscopy. Enhanced hot forgeability was then demonstrated by hot forging studies in an industrial environment. Both SPD processed material and conventional forging stock material were used to produce several forgings. Results indicate that the SPD processed material offers higher yield at lower billet temperatures. Heat treatment studies indicate that T6 properties can be achieved at significantly shorter aging times than conventionally processed material. The implications of the decreased material usage and the lower billet temperatures on energy and cost savings will be discussed.
Summary: This paper discusses the first use of severe plastic deformation (SPD) processed AA-6061 as forging stock to make several parts in an industrial setting. Results show this material can be processed at lower billet temperatures, and have higher material yield. Both these factors can contribute to energy and cost savings.