Microstructure and mechanical properties of friction stir welded 6082-T6 aluminium alloy

Abstract

Aluminium alloy 6082-T6 is vital in the fabrication of light weight structures requiring high strength-to-weight ratio and good corrosion resistance. In this work, investigation is carried out at three different heat energy inputs termed as hot weld (HW), cold weld (CW) and weld at optimum condition (WOC). Heat energy in friction stir welding depends on spindle speed and weld speed. The characteristic study of tensile strength, micro-hardness and metallographic structure at different weld conditions were carried out. Higher heat input, ie. HW, shows fine and harmonised grains, but softening occurred across the weld. Lower heat input, ie. CW, shows better mechanical properties compared with HW, but prone to brittle fracture. The WOC compromises the CW as well as HW and provides better results.

Keywords:

• Friction stir welding
• aluminium alloy 6082-T6
• heat energy
• mechanical property
• microstructure

Additional information

Notes on contributors

S Gopi

S Gopi received his BE degree in Production Engineering from Madras University, Chennai, India, in 2001, and ME degree in Engineering Design from Anna University, Chennai, India, in 2007. He is currently an Assistant Professor at the Department of Production Engineering, Government College of Technology, Coimbatore, India. He is a budding research scholar in the area welding, especially friction stir welding. He has published papers in different journals and conferences at national and international levels. His current work covers welding techniques, element design and analysis, operation research, optimisation techniques, and industrial automation.

K Manonmani

K Manonmani received her BE degree in Mechanical Engineering, ME degree in Engineering Design and PhD from Bharathiar University, India, in 1989, 1998 and 2007, respectively. She is currently an Associate Professor at the Department of Mechanical Engineering, Government College of Technology, Coimbatore, India. She has over 25 publications in different journals and conferences. Her current research includes welding techniques, especially high energy welding processes, as well as modelling of welding processes, vibration engineering, non-traditional optimisation and finite element analysis.