Numerical Modeling of Microstructure of Heat Affected Zone in Friction Stir Welded AA7075

Volume 1, Issue 1, October 2016     |     PP. 20-30      |     PDF (651 K)    |     Pub. Date: October 17, 2016
DOI:    490 Downloads     7918 Views  

Author(s)

A. Abdollah-zadeh, Tarbiat Modares University, Department of Materials Engineering, P.O. Box: 14115-143, Tehran, Iran
A. Mehri, Tarbiat Modares University, Department of Materials Engineering, P.O. Box: 14115-143, Tehran, Iran
S. Entesari, Tarbiat Modares University, Department of Materials Engineering, P.O. Box: 14115-143, Tehran, Iran
H. Assadi, Tarbiat Modares University, Department of Materials Engineering, P.O. Box: 14115-143, Tehran, Iran

Abstract
There is interest in the study and control of heat affected zone (HAZ) of the weld junctions, which is often regarded as the weakest point of the joints. In the present work, experimental and numerical analyses are used to characterize extension and microstructure of HAZ in friction stir welding (FSW) of 7075 Al alloy (AA) sheets. The thermal history was recorded by inserting thermocouples near the HAZ. These measurements were combined with a numerical modeling to predict thermal histories of various welding conditions. Moreover, the grain growth behavior of the base metal, including the growth kinetic constant, was determined through a series of isothermal annealing at different temperatures followed by grain size measurements. In this way, the grain structure of the HAZ could be linked to the welding conditions. A good agreement between the predicted and observed values was obtained over a wide range of conditions.

Keywords
AA7075; HAZ; Numerical modeling; Thermal cycle, FSW

Cite this paper
A. Abdollah-zadeh, A. Mehri, S. Entesari, H. Assadi, Numerical Modeling of Microstructure of Heat Affected Zone in Friction Stir Welded AA7075 , SCIREA Journal of Materials. Volume 1, Issue 1, October 2016 | PP. 20-30.

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