Effect of sintering on mechanical properties of cold sprayed thermal barrier coatings

Abstract

In this study, thermal barrier coatings were deposited on nickel-based super-alloy with CoNiCrAlY bond and yttria partially stabilised zirconia top coats, using cold gas dynamic spraying and atmospheric plasma spraying techniques, respectively. High temperature oxidation behaviour and sintering effect on the mechanical properties of the coatings were studied. The main objective of this work is to explain the alteration in coating structure depending on temperature, and the mechanisms that lead to alterations in mechanical properties such as Young's modulus and hardness. Structural examination after oxidation revealed a decrease in porosity content and crack healing on ceramic top coatings resulting from sintering effect.