The stability of Pt nanofilaments in a Au-matrix composite

Abstract

Au-7 at% Pt Deformation-processed Metal Metal Composite (DMMC) was isothermally annealed at various times and temperatures. Avrami and Arrhenius relations were used to evaluate the kinetics of the transformation from the initial metastable nanofilamentary microstructure to the equilibrium homogeneous solid solution condition. Results indicated that the activation energy for this transformation was 167 ± 6 kJ/mol. This activation energy is lower than activation energies reported in the literature for planar interface, single crystal Au-Pt diffusion couple experiments. The effects of chemical potential, surface curvature, and strain effects on the empirical activation energies determined in the DMMC of this study are discussed. These factors are thought to cause the DMMC systems to reach equilibrium faster.