Pressure-induced polyamorphism in Nd60Fe30Al10 and Ce70Al10Cu20 metallic glasses by high-energy X-ray diffraction and electrical resistance measurements

Abstract

ABSTRACTIn situ high-energy X-ray diffraction of Nd60Fe30Al10 and Ce70Al10Cu20 metallic glasses is carried out under high pressure. During compression, Ce70Al10Cu20 and Nd60Fe30Al10 exhibit a polyamorphic transition from low-density state below 2.0 and 10.0 GPa, to high-density state above 8.4 and 21.1 GPa, respectively. The intermediate hysteresis regions are the mixture of both phases. Electrical resistance measurements under high pressure show that Ce70Al10Cu20 display a discontinuous change in pressure dependence curve of resistivity at around 1.7 GPa. The addition of Fe atom gives a significant standoff of phase transition pressure in Nd60Fe30Al10. The results in this work suggest that the solute element and microstructure of lanthanide solvent aggregates have implications on the polyamorphic transition in metallic glasses.