Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Comparison between two surface preparations of WC-10Co-4Cr and their effect on erosion wear resistance
Submission Author:
Denis Marcel Pires Nagasima , SP , Brazil
Co-Authors:
Roberto Souza, Denis Marcel Pires Nagasima
Presenter: Denis Marcel Pires Nagasima
doi://10.26678/ABCM.COBEM2017.COB17-2628
Abstract
Tungsten carbide WC-10Co-4Cr is used in many hydro power generation components such as Francis, Pelton and Kaplan runners to improve surface properties and increase erosion wear resistance. The HVOF process is well known for coating manufacturing and, in addition to many benefits, is associated with failures that can happen during the process, such as cracks and coating detachment. In case of failures during application, the removal of all coating and reapplication is stablished as a good practice, because no coating shop can guarantee the coating quality in a repair. Considering these points, this work aims to understand the limitations of coating repair that uses two different kinds of surface preparation. The first one was the surface sandblasting with aluminum oxide and the second one was electrochemical partial removal of coating. Both preparations were followed by coating deposition and comparison in a slurry erosion test rig. Results indicate that surface roughness increase seems to be one of the key factors for repair improvement.
Keywords
coating, Erosion, HVOF, Tungsten Carbide, thermal spraying
