Effects of Pd addition on the glass forming ability and crystallization behavior in the Ni-Zr-Ti alloys

The effect of Pd substitution for Ti on the glass forming ability and crystallization behavior has been studied in Ni57Zr20Ti23-xPdx (x = 0, 3, 5, 7, 10) alloys. Partial substitution of Ti by Pd in Ni57Zr20Ti23-xPdx improves the glass forming ability. With increasing Pd content x, from 0 to 7, DeltaT(x) and T-rg increase from 15 to 43 K and from 0.59 to 0.64, respectively. Crystallization sequence becomes completely different with addition of Pd. The amorphous Ni57Zr20Ti23 alloy crystallizes via precipitation of only cubic Ni(Ti,Zr) phase in the first crystallization step, whereas the amorphous Ni57Zr20Ti16Pd7 alloy crystallizes via simultaneous precipitation of orthorhombic Ni-10(ZrTi)(7) and cubic NiTi phase. Addition of Pd in the Ni57Zr20Ti23 alloy suppresses the formation of the primary cubic Ni(Ti,Zr) phase, leading to the improvement of glass forming ability. (C) 2002 Elsevier Science B.V. All rights reserved.