Fatigue Behaviour of Friction Stir Welded AZ31B Magnesium Alloy Joints

Abstract:

Friction stir welding (FSW) is a relatively better joining technique particularly for magnesium and aluminum alloys that are difficult to weld by fusion welding techniques. Fusion welding of these alloys is not preferable due to hot cracking, formation of porosity, etc. However solid state welding techniques, such as, friction sitr welding are found to offer solution to the above problems. Many research papers available in open literature focusing tensile properties, microstructural characteristics, and corrosion behaviour of friction stir welded AZ31B magnesium alloys but fatigue behaviour of these welds are not yet investigated. Hence, in this investigation, an attempt has been made to evaluate fatigue behaviour of friction stir welded rolled plates of AZ31B magnesium alloys.Fatigue experiment was conducted using servo hydraulic controlled fatigue testing machine. Fatigue strength, fatigue notch factor and notch sensitivity factor were evaluated. It is found that the fatigue strength of AZ31B welded joints is 46 MPa at 2x10⁶ cycles which is approximately 34 % lower than that of the base metal fatigue strength.

• Periodical: Applied Mechanics and Materials (Volume 787)
• Pages: 355-360
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.787.355
• Online since: August 2015
• Authors: S. Venkatesan, G.P. Rajamani, V. Balasubramanian, G. Padmanaban
• Keywords: Fatigue, Friction Stir Welding, Magnesium

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