30-08-2017, 01:13 PM
CoNiCrAlY coatings sprayed with vacuum plasma are modified by cathodic vacuum arc cathodic deposition. The micro-structure and the oxidation resistance of the coatings are investigated. The parabolic law was obeyed for aluminised coatings after oxidation at 1100 ° C for 100 h. Its parabolic kinetic constant is 0.080 mg / cm 3 h, which is lower than that of the powder coatings. The continuous and dense scale of Al2O3 is formed earlier due to the increase in Al concentration, and the spinels hardly exist. The oxidation resistance is obviously improved after the cathodic vacuum arch cathodic deposition.