New Carbide Based Materials for HVOF Spraying

Abstract Standard materials like WC-Co, WC-CoCr, WC-Ni, and Cr3C2- NiCr for HVOF spraying exist in various modifications depending on chemistry, carbide size, and production method. They are widely used for wear, erosion, cavitation, and corrosion protection in many industrial fields. But there are a lot of applications in which the surface is exposed to a combination of different wear mechanisms - e.g. corrosion and erosion or abrasion - and usual state-of-the-art coatings do not fully meet the technical demands regarding lifetime under those combined attacks. New materials therefore are needed. In the present study several modified and completely new carbide based materials are investigated. A series of new cermets differing regarding carbide type, carbide size, and metallic binders are compared. The materials were sprayed with the HVOF system DJ 2600 to show the influence of their different chemistry and morphology on the microstructure and properties of the coating in comparison to standard materials. The experiments comprises microstructural examinations as well as abrasive wear, corrosion, and cavitation tests.