A combinatorial study on the influence of elemental composition and heat treatment on the phase composition, microstructure and mechanical properties of Ni-W alloy thin films

Ni-W alloys are promising materials for applications where mechanical stability at relatively high temperature is required Several Ni-W thin film gradients were synthesized by magnetron sputtering spanning the entire binary composition range Microstructure and phase composition were characterized by means of X-ray diffraction and transmission electron microscopy, while the mechanical properties were assessed using nanoindentation As-deposited films exhibit non-equilibrium phases such as amorphous phases in the center of the phase diagram and beta-tungsten in the tungsten-rich regime After annealing, a new X-phase is observed in the center of the phase diagram and non-equilibrium phase compositions are observed for most compositions, such as the presence of alpha-tungsten at a composition of 75% Ni Microstructure and composition were successfully correlated to the mechanical properties (C) 2010 Acta Materialia Inc Published by Elsevier Ltd All rights reserved