The Reactive Element Effect

Abstract Rationalizing the reactive element effect operative in alumina- and chromia-forming alloys upon oxidation under oxidizing hot gas atmospheres, referring to investigations on zirconium oxide-coated test samples for turbine alloys. This retrospective study uses results of cyclic furnace lifetime tests conducted at 1100 °C ZrO 2 -coated Ni-base with Y? or Y+ Hf-doped bond coats correlates them parabolic rate constant binary NiAl doped Y, Zr, Hf. Parallel higher temperatures allow respective processes during lifetimes be assigned cation-dominated anion-dominated transport processes. The correlations document close interrelationship between refractory content (Mo, Re, Ta, W) substrate alloy total two elements Y Zr mixed zone scale, representing a Me 3+ iso-valence value individual relative parameters pct EBPVD thermal barrier coating systems associated