Influence of plasma spray parameters on mechanical properties of yttria stabilized zirconia coatings. I: Four point bend test

Yttria (8 wt.%) stabilized zirconia (YSZ) with a NiCrAlY bond coat was atmo sphere plasma sprayed on mild steel substrates. The bond coat thickness (10 0-250 mu m), YSZ coating thickness (300-500 mu m), stand off distance (80-1 00 mm), and substrate temperature (273-393 K) were changed in a four by 17 experimental design matrix to investigate the influence of each spray param eter on the mechanical properties of coatings. Coatings were tested using a four point bend test arrangement. Coatings sprayed with thinner bond coat on a cold substrate exhibited higher yield strength and stiffness under ben ding. Change in the stand off distance and the top coat thickness did not s tatistically influence either yield strength or stiffness of the coatings. (C) 2000 Elsevier Science S.A. All rights reserved.