Effect of microalloying on the formation and stability of the Ti–Zr–Ni icosahedral quasicrystal

Abstract

The influence of small additions of Cu, Ag, Au, Pt, Pb, and Si on the formation and stabilization of Ti–Zr–Ni icosahedral quasicrystal (i-phase) are discussed. Among these elements, only the addition of Ag improved the stability and formability of the i-phase, significantly. A small amount of supercooling and the nucleation and growth of only the i-phase from the liquid during levitation melting experiments signal the presence of well developed extended icosahedral short range order (ISRO) in the liquid. These results are explained in terms of a better atomic size ratio of Ag to Zr to form ISRO.