The Effect of Friction Stir Process (FSP) on the Microstructure and Mechanical Properties of Mg-Gd-Ag-Zr Alloy

Abstract:

An Mg-13.0Gd-1.6Ag-0.3Zr (wt.%) alloy casting was subjected to friction stir processing (FSP) at a tool rotation rate of 500 rpm and a traverse speed of 100 mm/min. The effects of FSP on the microstructures in different zones and mechanical properties were investigated. It indicates that FSP can result in significant break-up and dissolution of the coarse eutectic secondary phase‑‑Mg₅Gd-type, and remarkable grain refinement (~2.5 µm) in stirring zone (SZ). Therefore, the mechanical properties of the casting can be significantly improved after FSP, i.e., it exhibits an ultimate tensile strength of 341 MPa and an elongation of 17 %.

• Periodical: Materials Science Forum (Volume 765)
• Pages: 726-730
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.765.726
• Online since: July 2013
• Authors: Fei Yan Zheng, Li Ming Peng, Yu Juan Wu, Xue Wen Li, Yu Zhang, Wen Jiang Ding
• Keywords: Friction Stir Processing (FSP), Grain Refinement, High Strength, Mg Alloy

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