Microstructure Formation and Mechanical Property Involving Icosahedral Quasicrystal Phase of Y Rich Mg-Zn-Y Quasicrystal Alloy

The microstructure formation and mechanical property involving icosahedral quasicrystal (I-phase)in the Y-rich Mg-Zn-Y alloy have been studied. The equilibrium formation of I-phase from the Y-richMg-Zn-Y melt is through a peritectic reaction between the Y-rich melt and the primary W-phase,which is discussed in detail. The independent nucleation and coupling growth mechanism betweenthe W-phase and the I-phase, from the melt, are revealed, which is significant for understandingthe peritectic reaction process involving icosahedral quasicrystal in the Mg-Zn-Y alloy. Themechanism of the quasicrystal phase strengthened magnesium alloys is also discussed here.