| Nanophased WC–12Co Thermal Spray Coatings for Wear Resistant Applications | ||
| Mr. Nikolaos Petsas1, George Papapanos1, Prof. Jean-Pierre Celis2, Prof. Paolo Matteazzi3, Prof. Angeliki Moutsatsou4 and Dr. Michalis Vardavoulias1, 1PyroGenesis S.A., Technological Park of Lavrio, Lavrio, 19500, Greece, 2Katholieke Universiteit Leuven, Kasteelpark Arenberg 44, Leuven, B-3001, Belgium, 3CSGI, Via G. Bortolan 42, Vascon di Carbonera (TV), 31050, Italy, 4National Technical University of Athens, 9 Iroon Polytechniou, Athens, 15773, Greece The purpose of the present study is to investigate the influence of critical HVOF spray parameters on mechanical properties of WC–12Co coatings, using nanophased powder as feedstock material. For this reason, the Taguchi design of experiments method was used for the development and optimization of process parameters and coating properties. An L9 table was used for the evaluation of the effect of spray distance, oxygen/fuel ratio, gun traverse speed and feed rate on coating microhardness, adhesion strength, porosity and deposition efficiency – thickness. Results show clearly that each parameter affects in a different way and percentage each property. Furthermore, the comparison of XRD diagrams with a respective conventional coating indicates that the nanostructure of the initial powder is maintained in the coating, whereas in the conventional one the formation of W2C phase is evident. Finally, fretting tests show similar behavior in terms of friction coefficient, but a significant improvement regarding wear resistance in the case of the nanophased coating. | ||