Nanostructurization of Magnesium Alloy via Friction Stir Lap Processing

Abstract:

Friction stir processing (FSP) in a lap configuration of a metal sheet and an alloy plate has been examined to produce surface alloy layer with nanostructures. The 1-pass friction stir lap processing (FSLP) over 0.5 mm-thick Cu sheet on an AZ91 substrate produced multilayer structure with nanograins and/or nanoprecipitates in each layer, but the structure distributed only partially in the stir zone (SZ). Through the 3-pass FSLP along the same line, the multilayer structure has disappeared and the fine structure with precipitates in size ranging from several 100 nanometer to 3 micrometer has yielded among the entire SZ. 2-dimensional microhardness mapping have shown that the standard deviation of microhardness values in the SZ has decreased by half from 1-pass to 3 pass FSLP. Homogeneous microstructure involving nanostructures has been successfully produced via multi-pass FSLP.

• Periodical: Materials Science Forum (Volumes 838-839)
• Pages: 332-337
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.838-839.332
• Online since: January 2016
• Authors: Yoshihisa Kimoto*, Toru Nagaoka, Hiroyuki Watanabe, Masao Fukusumi, Yoshiaki Morisada, Hidetoshi Fujii
• Keywords: Friction Stir Processing, Mg-Cu Alloy, Multilayer, Nanoprecipitate, Ultra-Fine Grained Alloy

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