Evolution of Elastic Properties of Cold Sprayed Metal Coatings at Elevated Temperatures

Abstract

Resonant ultrasound spectroscopy was applied to analyze the temperature evolution of shear modulus of thick aluminum, nickel, copper and titanium coatings prepared by cold spraying in the temperature range 20 • C→560 • C→20 • C. The results show that the thermal cycle leads to a significant increase in the shear modulus of nickel, while for copper, titanium and aluminum the shear modulus remains nearly unchanged or exhibits a weak increase only. Evolution of the internal friction parameter shows a significant decrease after the thermal cycle, being the most pronounced for nickel again. The decrease of the internal friction observed in the studied coatings indicates grain coarsening and consequent lower influence of grain boundary sliding.