Effect of hot rolling and heat treatment on anisotropy properties of Mg alloy LZ71

Subject Areas :

Mostafa Pahlavani ¹ ( School of Automotive Engineering, Iran University of Science and Technology )
Javad Marzbanrad ² ( School of Automotive Engineering, Iran University of Science and Technology )
Abbas Bayati ³ ( School of Mechanical Engineering, Iran University of Science and Technology )

Received: 2018-04-23 Accepted : 2019-08-06 Published : 2019-08-28

Keywords: LZ71, Mg Alloy, Heat treatment, Anisotropy, Hot rolling,

Abstract :

In this paper, a study was carried out on the mechanical and metallurgical properties of magnesium-lithium dual phase alloy. After casting the alloy, the thickness of primary billet is reduced from 10 mm to 2 mm using hot rolling. Then, in order to achieve an isotropic sheet, the rolled part was heat treated at 350 °C. The microstructure of samples were studied using optical microscope to observe the type of grain size variation. In the present survey, anisotropy of hot rolled LZ71 sheet has been studied for the first time. For this purpose, Mechanical properties of all three samples: after casting, after rolling and after heat treatment in three directions of longitudinal and transverse and 45 degrees were completely investigated. Moreover, the anisotropy coefficients of the rolled samples were calculated and evaluated. Results were found that, the alloy had suitable specifications for structural applications before and after heat treatment, but anisotropy was observed in samples without heat treatment. Finally, the failure level for samples after rolling and after heat treatment process was examined to confirm the anisotropy results.

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