Influence of Friction Stir Welding Parameters on the Mechanical Properties of EN AW-7075 Weld Joints

Abstract:

The paper deals with the friction stir welding (FSW) of the high strength EN AW 7075-T651 aluminium alloy with the aim to analyze the influence of welding parameters on the mechanical properties of Al-weld joints. FSW represents relatively novel solid-state technology of material joining which can be successfully applied for welding of several metallic alloys including the high-strength aluminium alloys that are hard to weld by conventional fusion welding processes. In cooperation with VÚZ - PI SR Bratislava, nine experimental weld joints of samples with dimensions of 300 × 150 × 10 mm were prepared using the welding machine of the FSW-LM-060 type and different parameters of welding – the welding speed from 60 to 120 mm/min and the tool rotation rate from 600 to 1000 rpm in clockwise direction. The quality of weld joints was evaluated by static tensile tests and micro-hardness measurements. According to obtained results of tensile testing, the average values of ultimate strength of weld joints are by 32.2 % lower comparing with the ultimate strength of the base material. On the other hand, the ductility increased by 7.2 %. The highest micro-hardness of weld joints at the level of 129 HV was measured in thermo-mechanically affected zone on the retreating side.

• Periodical: Applied Mechanics and Materials (Volume 835)
• Pages: 210-215
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.835.210
• Online since: May 2016
• Authors: Máté Nagy, Mária Behúlová*
• Keywords: FSW, High Strength Al Alloy, Mechanical Property, Welding Parameters

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