Improved Corrosion and Wear Resistance Characteristics of Thin, High Performance WC-CoCr Coatings Using Ultra Fine Powders

A method is described for increasing the density, as well as corrosion and wear resistance properties, of WC-CoCr coatings by using ultra fine powders and a Temperature Controlled HVOF process. These coatings are applied to ground surfaces eliminating the need for blasting and thereby the detrimental effects of blast particles embedded in the substrate.  Axial Fatigue test results, Bend tests results, Pin-on-Disk test results and salt spray test results are presented and compared with standard HVOF techniques. The results indicate that similar corrosion and wear properties can be achieved with thinner coatings.

Furthermore results will be presented from tests with Multi-Layer thin coatings. Thin, high performance WC-CoCr coatings are sealed with a Diamond Like Carbon (DLC) layer deposited in a PA CVD process. The resulting Multi-Layer thin coatings display improved corrosion resistance as well as reduced friction and wear properties.