Effect of Extrusion Temperature on Microstructure and Mechanical Properties of 7A36 Aluminum Alloy

Abstract:

The microstructure, texture distribution, tensile property and fracture toughness of 7A36 aluminum alloy profile were investigated by optical microscopy (OM), scanning electron microscopy (SEM), electron back scattered diffraction (EBSD), tensile and toughness tests, respectively. The results show that when extrusion temperature increased from 410 °C to 430 °C, the second phase grew and the intensity of aging state alloy increased. With the extrusion temperature increased, the fracture toughness and elongation increased firstly and the decreased. The fracture toughness K_IC can reach to 46.47 MPa·m^1/2 at 420 °C. The extruded and final state of the 7A36 profile was dominated by the textured texture (Brass, S, and Copper), accompanied by a small amount of recrystallized type texture (Cube and Goss). As the extrusion temperature increased, the hard deformation texture increased, resulting in an increase in strength. The increase of extrusion temperature led to the increase of dynamic recrystallization fraction. The dynamic recrystallization fraction of the extruded state was 2.26 % when extrusion temperature was 430 °C. The change in K_IC performance is the combined result of re-crystallization, second phase and texture.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 108-115
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.108
• Online since: May 2020
• Authors: Ze Yu Zhou, Xiang Xiao, Kang Du, Cheng Liu*, Dan Lv, Xin Yu Lv
• Keywords: 7A36 Aluminum Alloy Profile, Extrusion Temperature, Tensile Property, Texture Distribution

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