Stoichiometric icosahedral phase in the Zn–Mg–Y system

Abstract

Stoichiometric composition and formation process of the icosahedral phase in the Zn–Mg–Y system have been studied. The icosahedral phase exhibit a stoichiometric composition in the vicinity of Zn₆₀Mg₃₀Y₁₀. During cooling, (Zn, Mg)₅Y phase primarily crystallizes from the melt at ∼960 K and then undergoes a peritectic reaction with the residual Mg-enriched melt (∼820 K) to form the icosahedral phase. The melt with a constant composition close to Mg₇Zn₃ is in equilibrium with the (Zn, Mg)₅Y phase above the peritectic temperature in a wide compositional range.