Melting of Ni40Pd40P20 glass

Abstract

Upon reheating, most glassy metal alloys crystallize at a temperature not far removed from the glass temperature Tg and far below the liquidus temperature Tl. We have reported that the alloy Ni40Pd40P20, which exhibits a scaled glass temperature ∼0.68, has been melt quenched, under a flux of dehydrated B2O3, to glass at rates as low as 1°/s. Here we report experiments in which some specimens of this alloy, when similarly fluxed during reheating, have been reheated to temperatures within 50° of Tl and 280° above Tg at rates ∼2.5°/s, and then cooled again to Tg, without crystallization. From this behavior we infer that the steady frequency of homogeneous nucleation of crystals in the alloy is <10−1 cm−3 s−1.