Mechanical and Microstructural Characterization of Aluminum 6061 Processed by Plane Stress Local Torsion

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Vol. 45; no. 2; pp. 507 - 514
• Main Authors: Shamdani, Amir Hossein, Khoddam, Shahin
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.04.2014; Springer Nature B.V
• Subjects: Aluminum alloys; Characterization and Evaluation of Materials; Chemistry and Materials Science; Finite element method; Grain refinement; Materials Science; Mathematical analysis; Mechanical properties; Metallic Materials; Microstructure; Nanotechnology; Plane stress; Simulation; Stress analysis; Structural Materials; Surfaces and Interfaces; Thin Films; Torsion; Solution Heat Treatment; Ductile Iron; Torsion Test; Equivalent Plastic Strain; Severe Plastic Deformation
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-013-9915-8

The process of plane stress local torsion (PSLT) has been recently proposed as localized severe plastic deformation to enhance the mechanical properties of the fastener holes. The PSLT process can create large shear strains and, consequently, substantial grain refinement in the vicinity of the hole with a gradient in the radial direction. It is of great interest and importance to investigate the effect of the PSLT process on a range of materials commonly used in the industry. An introductory investigation of mechanical and microstructural properties of Al6061 samples processed by the PSLT is performed in this work. The PSLT is simulated using the finite-element method, and the torque twist curves obtained from finite-element simulations are compared with experimental measurements. Microstructural changes and the extent of grain refinement are investigated by means of optical microscopy. It is shown that the PSLT is responsible for a considerable improvement in the mechanical properties within the deformation zone. The microhardness tests were used to measure the degree of enhancement in ultimate and yield strengths of the material processed by the PSLT.