Solid Stir Extrusion: Innovating friction stir technology for continuous extrusion process

Solid Stir Extrusion (SSE) is an innovative friction-stir technology based process developed to obtain an extrudate of the preferred shape. As a solid-state manufacturing process, SSE embodies several benefits such as lower power consumption, continuity over a greater time frame, wide material range applicability, and flexibility to large-scale customization. This study demonstrates the feasibility of the SSE process using Al 6061-T6 as a feedstock material. Process outcomes like force and torque are correlated with comprehensive microstructural and mechanical characterization. The extrudate possessed a fine equiaxed grain structure (∼10–15 µm) with improved ductility as compared to the base material (∼100 µm). Post-process heat treatment additionally improved the mechanical properties of the extruded material. DSC analysis elucidates the effects of heat treatment. A conceptual model is proposed to correlate process parameters to process outcomes.