Microstructure Evolution and Mechanical Properties of AZ61 Mg Alloy Processed by Two-Pass Friction Stir Processing

Abstract:

Friction stir processing (FSP) has been considered as a promising technique for grain refinement. In this study, two-pass FSP was conducted under water to enhance the cooling rate during processing, and a fine-grained AZ61 magnesium alloy was prepared through this method. Compared with one-pass FSP, the microstructure of two-pass FSP alloy is more homogeneous and finer, with an average grain size of 1.8 μm. Both the tensile strength and ductility of the two-pass FSP sample are improved due to grain refinement. A tensile elongation of 31.8% was achieved in the two-pass FSP sample. The microstructure evolution mechanism during the processing was discussed based on the microstructure examination.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 272-277
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.272
• Online since: June 2017
• Authors: Xi Cai Luo, Da Tong Zhang*, Wen Zhang, Cheng Qiu
• Keywords: AZ61 Magnesium Alloys, Friction Stir Processing, Mechanical Properties, Microstructure

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