Effects of Substrate Treated by Dry-Ice Blasting on the Form of CoNiCrAlY Splats

Dry-ice blasting, as an environmental-friendly method, was introduced and used to treat the substrate to be coated. It is commonly admitted that a favorable surface condition tends to suppress the splashing of droplets and to promote the occurrence of disc-shaped splats. In the present paper plasma-sprayed CoNiCrAlY splats were examined on the treated substrate. The temperatures of CoNiCrAlY splats were also measured using an infrared pyrometer system. The results show that dry-ice blasting significantly influences the substrate surface condition and consequently influences the splat morphology. Moreover, there is a critical treatment time of dry-ice blasting in order to obtain regular disk-like splats.