Detonation Spraying of Metal Carbides Composites
Detonation spraying is used for the binary fuel spraying, C2H2/C3H8/O2 of WC/Co and Cr3C2/NiCr powder. The particles-in-flight temperature and velocity are calculated and optimized. Spraying distance is varied from 50 to 400 mm and substrate inclination relatively spraying direction is varied up to 60o. Coating properties: microstructure, microhardness, porosity, wear resistance are measured and it is found that binary fuel detonation spraying provides high coating quality. For example, for the WC/Co (88/12 wt%) coatings: porosity is less than 0.7%; microhardness is about 1500 HV300; ASTM G65 abrasion wear is 1.17 mm3/1000 rev when using a corundum powder as an abradant. For the Cr3C2/NiCr (75/25 wt%) coatings porosity is less than 1.7%, microhardness is about 800 HV300, and abrasion wear is 2.7 mm3/1000 rev. It is found that the coating performance does not decrease strongly with the substrate inclination up to 30o. The industrial applications include machinery, aircraft, petrol, gas turbines domains, etc.