Grain Refinement and Dispersion Precipitation of I-Phase in Mg-Zn-Y Alloy Processed by ECAP

Abstract:

Equal channel angular pressing (ECAP) has been conducted on as-extruded Mg-Zn-Y alloy containing quasicrystal phase at a temperature of 523 K. The optical images indicate that after 8 ECAP passes through route BA, the grain size of the extruded alloy is decreased sharply; and the coarse eutectic icosahedral quasicrystal phases (I- phases) are broken and dispersed in the alloy; and the distributions of Zn and Y elements become more homogeneous. These can be attributed to the shear effect during the ECAP processing. TEM micrographs show the grain refinement, the evolution of broken and dispersed I- phases and dispersion precipitation of nano I-phases during 1- ,4- and 8- pass ECAPed Mg-Zn-Y alloy. And the mechanism of grain refinement is also discussed.

• Periodical: Materials Science Forum (Volumes 667-669)
• Pages: 593-598
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.667-669.593
• Online since: December 2010
• Authors: Guang Hui Min, Hong Wei Cui, Qing Liang Lu, Pan Gao, Hua Shun Yu
• Keywords: Equal-Channel Angular Pressing (ECAP), Grain Refinement, Icosahedral Quasicrystal Phase, Mg-Zn-Y Alloy

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