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

• Published in: Materials science forum Vol. 898; pp. 272 - 277
• Main Authors: Luo, Xi Cai, Zhang, Wen, Qiu, Cheng, Zhang, Da Tong
• Format: Journal Article
• Language: English
• Published: Pfaffikon Trans Tech Publications Ltd 19.06.2017
• Subjects: Alloys; Cooling rate; Ductility; Elongation; Evolution; Friction; Grain refinement; Grain size; Magnesium base alloys; Mechanical properties; Microstructure; Tensile strength; Friction Stir Processing; Mechanical Properties; Microstructure; AZ61 Magnesium Alloys
• ISSN: 0255-5476; 1662-9752; 1662-9752
• DOI: 10.4028/www.scientific.net/MSF.898.272

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.