Impact and Tensile testing of A12024 alloy processed by Friction Stir Processing

摘要

Friction stir processing (FSP) is a prominent technique of severe plastic deformation (SPD) that can provide modification and control of microstructure to enhance the mechanical properties of Al alloys, which can be used in aerospace and aircraft applications. The present work focuses on the evaluation of mechanical and impact behavior of Al 2024 alloy processed with FSP using a non-consumable round pin tool. The length of tool pin is considered to be 4.5 mm for performing FSP on Al 2024 plates having 6 mm thickness. The tool feed rate is maintained at 25 mm/min and tool rotational speed is considered as 1200 and 1800 rpm. Mechanical evaluations were conducted by determining microhardness, tensile tests and Izod impact test for different specimens. The maximum hardness is observed to be 155 HB in the nugget zone at the rotational speed of 1200 rpm, which is about 1.5 times of unprocessed specimen. The ultimate tensile strength also exhibits an increase of 20% for specimen processed at 1800 rpm. Fracture morphologies indicate that the dimple size and distribution on fractured surface is affected by the variation of rotational speeds. The impact test indicate that the impact strength increases by 2.5 times of unprocessed specimen at 1800 rpm.