|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Effective Dispersion of Stable Quasicrystals in ZW82 and ZA63 Alloys for Strengthening
||Karel Tesar, Hidetoshi Somekawa, Alok Singh
|On-Site Speaker (Planned)
Magnesium alloys reinforced with quasicrystalline icosahedral (i-) phase have been reported to show very high strength combined with good ductility due to very fine grain size and moderate texture on extrusion. Here we show that on processing by extrusion in two steps, ZW82 (Mg-3Zn-0.5Y in at%) and ZA63 (Mg-2.3Zn-2.8Al in at%) alloys show a uniform distribution of i-phase particles, resulting in homogeneous microstructure such as uniform grain size. Phase (particle) distribution, grain structure, microtexture and related parameters were determined. Mechanical behavior was evaluated by tensile and compression tests. Finer particle distribution resulted from breakage and refinement of the existing particles, resulting in full recrystallization reported in ZW82 for the first time. Consequently, a tension-compression yield symmetry was achieved even with a relatively large grain size of about 5 micron. Precipitation of stable i-phase was discovered in ZW82 alloy. I-phase precipitates exerted a strong pinning effect on grain boundaries.
||Magnesium, Process Technology, Phase Transformations