Exploring Microstructural, Textural, and Mechanical Properties in Bulk-Area Stir Zone Fabrication Through Overlapping Friction Stir Processing with Water Cooling
摘要
In this study, a bulk-area stirring zone (BSZ) was generated within the Al–Mg–Si alloy using friction stir processing with a combination of pin overlapping and water cooling. Detailed examinations were conducted on various aspects, including microstructural evolution, intermetallic behavior, crystallographic texture, and mechanical properties. The bulk-area stir zone (BSZ) microstructure contains an equiaxed fine-grained structure with more fraction of high-angle grain boundaries due to intense plastic straining and dynamic recrystallization. The grain refinement remained consistent across each overlapping pass, typically within the range of 3 to 4 µm. Notably, the BSZ exhibited the formation of A1-{111}(112) texture components with a maximum intensity of 5.4 owing to the material flow caused by the tool’s revoluting nature around the pin. The hardness distribution across the BSZ was found to be uniform and aligned with the grain size values. The combined effects of material softening and intermetallic dissolution in the BSZ led to a substantial enhancement of 127% in ductility.