Abstract
In this paper, the effect of heat treatment and number of passes on microstructure and mechanical properties of friction stir processed AZ91C magnesium alloy samples were investigated. From six samples of as-cast AZ91C magnesium alloy, three plates were pre-heated at temperature of 375°C for 3 hours, and then were treated at temperature of 415°C for 18 hours and finally were cooled down in air. Three plates were relinquished without heat treatment. 8 mm thick as-cast AZ91C magnesium alloy plates were friction stir processed at constant traverse speed of 40 mm/min and tool rotation speed of 1250 rpm. After process, microstructural characterization of samples was analyzed using optical microscopy and tensile and Vickers hardness tests were performed. It was found that heat treated samples had finer grains, higher hardness, improved tensile strength and elongation relative to non-heat treated ones. As the number of passes increased, higher UTS and TE were achieved due to finer grains and more dissolution of β phase (Mg17Al12). The micro-hardness characteristics and tensile improvement of the friction stir processed samples depend significantly on grain size, removal of voids and porosities and dissolution of β phase in the stir zone.
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Mojtaba Dadashpour received his B.S. Degree in Mechanical Engineering at Tabriz University (2000) and M.Sc. Degree in Mechanical Engineering at Orumiyeh University (2003). He is a Ph.D. student in Mechanical Engineering of Ataturk university. All degrees are in Mechanical Engineering.
Ruhi Yeşildal graduated Aksaray Industrial Vocational High School in 1971. He received his license from Gazi University Technical Education Faculty Department of Mechanical in 1979, Master degree from Department of Mechanical Engineering, Graduate School of Science, Atatürk University in 1993, and his Ph.D. from Atatürk University in 1999.
Amir Mostafapour received his B.S. Degree in Mechanical Engineering from Tabriz University in 1993, his M. Sc. Degree in Mechanical Engineering from University of Amirkabir, Tehran in 1997 and his Ph.D. student in Mechanical Engineering from University of Amikabir, Tehran in 2006. His all degrees are in Mechanical Engineering.
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Dadashpour, M., Yeşildal, R., Mostafapour, A. et al. Effect of heat treatment and number of passes on the microstructure and mechanical properties of friction stir processed AZ91C magnesium alloy. J Mech Sci Technol 30, 667–672 (2016). https://doi.org/10.1007/s12206-016-0121-x
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DOI: https://doi.org/10.1007/s12206-016-0121-x