Microstructure and Texture Evolution of 0.6 mm Ultra-Thin-Walled Tubes of Magnesium Alloys Fabricated by Multi-Pass Variable Wall Thickness Extrusion (VWTE)

Abstract:

AZ80+0.4%Ce alloy ultra-thin-walled tube with a wall thickness of 0.6 mm was fabricated by multi-pass variable wall thickness extrusion (VWTE) at 693 K. Microsturcture and texture evolution were investigated. The results indicate that the average grain size decreases from ~47 μm of extruded alloy to ~8.9 μm after 5 passes VWTE. The total area reduction of Mg alloy tube is 91 %. Homogeneity of microstructure is improved obviously and the morphology of Mg₁₇Al₁₂ phases in coarse grains and fine DRXed grains exhibit lamellar and granular shapes, respectively. In addition to the microstructure evolution, the VWTEed tubes showed a strong texture of (0001) planes, and the intensity decreased with deformation increasing to 4 passes. After 5p-VWTE, a strong texture characterized by (0001) pole tilting 20 degrees rotated from extrusion direction (ED) towards normal direction (ND).

• Periodical: Materials Science Forum (Volume 993)
• Pages: 427-433
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.427
• Online since: May 2020
• Authors: Zhao Ming Yan, Zhen Dong Lian, Min Fang*, Zhi Min Zhang, Jia Xuan Zhu, Guan Shi Zhang, Long Zhang
• Keywords: Microstructure, Texture, Ultra-Thin-Walled Tubes, VWTE

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