Tribological and Oxidative Behavior of Thermally Sprayed NiCrBSi Coatings

The behavior of NiCrBSi coatings deposited by three different spraying techniques was studied: flame spray with a subsequent flame treatment (FS + Flame), flame spray with post-laser treatment (FS + Laser) and laser cladding (LC). The coating responses under wear and oxidation conditions were analyzed. Although the microstructure of the coatings deposited by the three different techniques showed similar phases and precipitates, some changes in the size and distribution of these constituents were observed. The pin on disk configuration was used to determine the friction coefficients and wear rates. LC coatings showed the highest wear resistance, with plastic deformation being the main wear mechanism identified for all of the coatings analyzed. Tests under aggressive environments were also performed to determine the oxidation kinetics.