HVOF COATINGS
The admittedly good characteristics of coatings obtained by traditional spray techniques (wire metallisation, plasma spraying and flame-proofing) cannot always fully meet particularly demanding functional requirements due to limitations in anchorage, corrosion between particles or excessive porosity. These limitations, which strongly condition extreme wear and corrosion applications under even heavy loads or fluid pressures, are greatly reduced by using the HVOF technique.
The density due to a high cohesion value of the structure makes HVOF coatings very resistant to abrasive and erosive wear. Tungsten Carbide coatings, due to their exceptional hardness characteristics and high carbide content compared to the matrix, offer the possibility of numerous applications, which are not always satisfactory with other techniques.
The material on which the coating is made is not deformed because the temperature is contained within 150°C. There are no structural changes.
HVOF coatings are applicable in thicknesses ranging from a few hundredths to a few tenths (0.3 - 0.5).
The finish varies according to the requirements of the part, from a Ra. 4 - 5 rough, to Ra. 0.05 lapping.
