Cobalt-based PTA coatings, effects of addition of TiC nanoparticles

• Published in: Vacuum 2017-09, Vol.143, p.14-22
• Main Authors: Acevedo-Dávila, J.L., Muñoz-Arroyo, R., Hdz-García, H.M., Martinez-Enriquez, A.I., Alvarez-Vera, M., Hernández-García, F.A.
• Format: Article
• Language: English
• Subjects: Coefficient of friction; Nanoparticles; Nanostructured filler; Nanowhiskers; Stellite
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2017.05.033

The novel filler metals of cobalt-based alloys reinforced with titanium carbide nanoparticles (TiC-NPs) were used for the fabrication of plasma transferred arc hardfacing coatings. The effect of tribological behavior for TiC-NPs addition on two Co-based filler metals (Stellite 6 and Stellite 12), as well as the dilutions, was studied. Mixtures of Co-based filler metals without and with 0.5% and 2% TiC-NPs were deposited onto D2 steel plates. Stellite 12 had an increase in the dilutions (70%) and enthalpies due to a major surface energy and endothermic reactions. The results of DSC (Differential Scanning Calorimeter) in the filler metals with TiC-NPs showed a shell of nanowhiskers on the sintered surface, which were observed and chemically analyzed via SEM (Scanning Electron Microscope) and EDS (Energy Dispersive Spectroscopy). Stellite 6 with 2% TiC-NPs was the most effective in increasing the wear resistance. These outcomes might be of interest for mining industries, where machinery and equipment are exposed to extreme wear conditions. •Decomposition from TiC to Ti ionic reacts with N+ to form TiN.•TiN is found in the interdendritic regions as well as in particles.•Sizes and distribution different of TiN particles are formed in the coating.•The plasma can condensed Ti to form nitrides with environment.•Combined effects of NPs and W-rich compounds increase the wear resistant.