Table III.

Summary of Samples, Coatings, Processing and Experimental Conditions

		CMSX-4			RR3010
		As-Coated	2-pt Bend Tested		As-Coated	2-pt Bend Tested
			Air	Air + Salt		Air	Air + Salt
Pack Aluminide	non-grit blasted	uniform ~ 80 μm thick coating constituted primarily of NiAl intermetallics	thin cracks throughout the coating, stopping at the inter-diffusion zone	thicker cracks throughout the coating, stopping at the inter-diffusion zone	uniform ~ 80 μm thick coating constituted primarily of NiAl intermetallics	thin cracks throughout the coating, stopping at the inter-diffusion zone	thin cracks throughout the coating, stopping slightly beyond the inter-diffusion zone
Vapour Aluminide	non-grit blasted	NiAl coating, ~ 25 μm thick	thin cracks throughout the coating, stopping at the inter-diffusion zone	thickest crack, throughout coating and into the bulk alloy (~ 300 μm). Secondary cracks in the inter-diffusion zone	NiAl coating, ~ 25 μm thick	thick cracks throughout the coating, stopping at the inter-diffusion zone	thick, tortuous cracks throughout the coating, stopping slightly beyond the inter-diffusion zone
	grit blasted	NiAl coating, less uniform interface with embedded grit particles. ~ 25 μm thick	did not crack	one very thin crack, 30 μm deep, did not penetrate the entire coating layer	—	—	—