Effect of Severe Plastic Deformation Involving Ecap of Aluminum 2024 Alloy Beryl Composites on the Mechanical Properties

Abstract

The adoption of Aluminum Metal Matrix composites has gained popularity and widespread application in view of their light weight and superior mechanical strength compared to the un-reinforced alloy system. Much improved characteristics have been derived based on the adoption of secondary processes such as rolling, forming, drawing and plastic deformation. In this context, the preparation of Al2024 alloy, containing Beryl particles as reinforcement is envisaged for getting better properties in terms of strength and hardness for structural use in aerospace industry. Further enhancement in properties to strengthen the alloy may be possible by subjecting it to severe plastic deformation, especially Equal Channel Angular Pressing (ECAP) process. The present work focuses on developing Al 2024 alloy composites containing Beryl particles at 6 wt.%, through stir cast method. This is followed by ECAP process carried out in the annealed condition. This facility has been designed and developed in house. Following this, the mechanical properties, involving tensile strength, % elongation & hardness have been evaluated for the ECAP processed Al2024 Beryl samples and the values thus obtained are compared with those derived on samples without Beryl additions. The microstructures of the samples, for key stages of the work, have been recorded. Further, the fracture morphology of ECAP processed samples have been examined and analyzed using SEM/EDAX and correlated with the tensile strength data. The ECAP with pass II processed samples have shown higher tensile strength and hardness as well as good grain refinement in the matrix compared to annealed Al alloy sample.