Erosion and corrosion resistant protective coating for turbomachinery methods of making the same and applications thereof

摘要

A wear resistant coating protects against corrosion and erosion of the thin metal protective sheath on turbomachinery applications. The coating has a metal layer overlaid by a ceramic layer. Multiple metal and ceramic layers can make up the coating with the layers varying in thickness allowing the layers nearer the substrate to remain more malleable to bend with the sheath and those layers nearer the top of the coating to be more brittle and resistant to wear. A cold spray metallic layer applied to the substrate provides a lightweight, flexible layer beneath the corrosion and erosion resistant protective multilayer coating.

主权项

1. An erosion and corrosion resistant protective coating for turbomachinery applications, the coating comprising:
at least two multilayer coating segments, a bottom segment applied to a surface of a conductive metal substrate and a top segment overlaying the bottom segment, each of the at least two multilayer coating segments having a combined thickness of at least about 40 μm to 300 μm, the at least two multilayer coating segments comprising a plurality of bilayers, the bilayers each comprising a metal layer overlayed by a ceramic layer, wherein metal content of the coating segment decreases from an area proximate the substrate to an area distal the substrate and hardness and elastic modulus of the coating segment increase from an area proximate the substrate to an area distal the substrate: wherein the surface of the conductive metal substrate is subject to a predeposition treatment by at least wet blasting, dry blasting, or powder spray to provide the surface with texture; wherein, hardness of the bottom segment is from about 0.3 GPa to about 25 GPa, and hardness of the top segment is from about 25 GPa to about 80 GPa; wherein, roughness of the erosion and corrosion resistant coating is Ra<1 μm; wherein, the erosion and corrosion resistant coating has a dome-like structure and dome width is from about 1 μm to about 20 μm; and wherein the metal layer and ceramic layer are blended into one another by concurrent condensation with ion bombardment from at least two metal-gaseous filtered cathodic arc plasma beams overlapped by a filtering focusing magnetic field, the deposition rate from about 3 μm/hr to about 30 μm/hr.