Tungsten carbide and chromium carbide based hard metal materials were sprayed with modern High Velocity Air-Fuel (HVAF) spray process to produce potential coating systems of the future components of pulp and paper, power and process industry. With the HVAF process novel dense hard metal coatings were produced. The test results showed significant improvements in performance by preventing the corrosive media from reaching the vulnerable substrate material. Furthermore, the abrasive wear rate of the HVAF sprayed coatings was decreased up to 40% compared to the industrial standard.
The increasing competition is pushing the companies to constantly improve their component performance and lifetime. This sets new demands for material solutions especially in harsh wear and corrosion environments that are encountered in e.g. paper machines, boilers and other industrial applications. Thermally sprayed hard metal coatings have established their place in these demanding applications mainly due to the large number of available material compositions and versatile deposition techniques/processes. While the coatings have found their way to numerous components, it has become increasingly important to improve the existing coating systems to stay at the forefront of the product development.
Significant improvements can be achieved by replacing some of the existing coating systems with the new HVAF sprayed hard metal coatings. Also, the improved properties open new possibilities to apply coatings in new components and environments where it has not been possible before.
Petri Vuoristo (TUT), Tarja Laitinen (VTT), Ville Eronen (Valmet Technologies)
TUT, VTT, Aalto, Valmet Technologies, Metso Automation, Telatek Service, Kuopion Konepaja, Virtasen Koneistamo, Abloy, Outotec, Oseir, Kokkola LCC, and TKM TTT Finland