Effects of Cooling Rate on Quasicrystal Microstructures of Mg-Zn-Y Alloys
Mg72.5Zn26Y1.5 quasicrystal alloys were investigated under different solidification conditions. The specimens of Mg-Zn-Y alloys with cooling rates from 13.2K/s to 69.8K/s were gathered by a designed multi-channel temperature acquiring system and then the microstructures and phase evolution of the alloys were analyzed. The results show that the precipitation temperature of icosahedral quasicrystal phase (I-phase) increased with cooling rate increased from 13.2 K/s to 69.8K/s. The microstructure was mainly made up of α-Mg, I-phase and Mg7Zn3 phase. Meanwhile, the quasi-crystalline morphology was significantly different in the experiments. It changed from five (six) petals to the big pentagon with the decreased cooling rate.
Guojun Zhang and Jessica Xu
Y. M. Wang et al., "Effects of Cooling Rate on Quasicrystal Microstructures of Mg-Zn-Y Alloys", Advanced Materials Research, Vols. 160-162, pp. 901-905, 2011