Quasi-crystalline materials with a unique combination of hardness, corrosion resistance and low friction coefficient are promising for the creation of wear-resistant coatings. The high-velocity oxygen-flame spraying (HVOF) method is an effective method for applying such coatings. The aim of this work is to study the surface properties of Al–Cu–Fe–B and Al–Co–Cu coatings obtained by the HVOF method.
The coatings were applied to a steel substrate by the HVOF method using Al–Cu–Fe–B and Al–Co–Cu powders. A profilometer was used to evaluate the surface roughness. Microhardness was measured by the Vickers method. Phase composition analysis was performed using X-ray diffraction. Surface wettability was assessed by measuring the contact angle.
This study is devoted to the investigation of quasicrystalline (QC) coatings of Al59Cu25.5Fe12.5B3 and Al65Co18Cu17 deposited by high-velocity oxygen-fuel spraying (HVOF). The coatings were characterized by analyzing their wettability and surface energy.
Polytetrafluoroethylene, bronze and austenitic stainless steel were also studied as comparative samples. The sessile drop method was used to determine the static contact angle, and the Owens-Wendt-Rabel-Koelble model was used to calculate the surface energy.
The obtained data were used to estimate the polar and dispersion components of the total surface energy. The results demonstrated that the QC coatings are characterized by a low level of surface energy comparable to that of polytetrafluoroethylene.
The Al–Cu–Fe–B and Al–Co–Cu coatings obtained by the HVOF method have high hardness and low surface roughness. X-ray phase analysis confirmed the presence of a quasi-crystalline phase in the coating composition. The values of the contact angle indicate the hydrophobic nature of the surface.
The results of the study demonstrate the possibility of obtaining quasicrystalline Al–Cu–Fe–B and Al–Co–Cu coatings by the HVOF method with high performance characteristics. The obtained data can be used to optimize the parameters of coating application and expand the scope of their application.
Author: Thiago A. Souza, David D. S. Silva, Francisco V. E. L. A. Junior, Francisco R. P. Feitosa, Rodini M. Gomes & Bruno A. S. G. Lima
Institute: Postgraduate Program in Mechanical Engineering, Federal University of Paraiba, João Pessoa, 58051-900, Paraiba, Brazil