Coatings for turbine parts
A method and a turbine part having a coating with a matrix layer that includes a high temperature resistant hydrophobic polysiloxane filler, wherein the coating has superior mechanical strength and temperature resistance.
1. A method for coating a part for an axially rotating machine with an erosion resilient coating, the method comprising:
providing a part of an axially rotating machine;
coating the part with a coating comprising a metal matrix having an embedded polysiloxane filler distributed throughout a thickness of the metal matrix; and
stoving the part with the coating employing a controlled process to tailor at least one of a temperature resistance and hydrophobic property of the polysiloxane filler, the controlled process employing a temperature that varies and is selected based at least in part on a required end use of the coating, a specific composition and form of the polysiloxane filler, and a presence of any catalytic substances; wherein the controlled process employs a temperature selected such that controlled partial pyrolysis results in successive replacement of carbon containing end groups with oxygen to form SiO2, yielding an increase in the ceramic (SiO2) to organic ratio of the polysiloxane filler to affect temperature resistance and hydrophobicity.
2. The method of claim 1 wherein the method of coating includes electrolytic nickel plating and/or electroless chemical coating.
3. The method of claim 1 wherein the method of coating comprises electrolytic nickel plating.
4. The method of claim 1 wherein the method of coating comprises electroless chemical coating.
5. The method of claim 1 wherein the coating the part with the coating results in a coating comprising an outer layer and an inner layer, the inner layer configured to be between the axially rotating machine part and the outer layer.
6. The method of claim 5 wherein the outer layer has the metal matrix comprising the polysiloxane filler distributed throughout an entire thickness of the outer layer.
7. The method of claim 6 wherein prior to coating the part with a coating comprising a metal matrix having an embedded polysiloxane filler, coating the part with a corrosion resistant layer that does not have any of the polysiloxane filler such that the polysiloxane filler is only within the outer layer of the coating.
8. The method of claim 7 wherein the controlled process further including ensuring that the polysiloxane filler undergoes controlled partial pyrolysis such that the polysiloxane filler includes polymeric hydrophobic filler particles operative to withstand temperatures exceeding 400° C.
9. The method of claim 1 wherein the controlled process further including ensuring that the polysiloxane filler undergoes controlled partial pyrolysis such that the polysiloxane filler includes polymeric hydrophobic filler particles operative to withstand temperatures exceeding 400° C.
10. The method of claim 1 wherein the metal matrix comprises Nickel or alloys thereof.
11. The method of claim 1 wherein the polysiloxane filler has a form of particles.
12. The method of claim 11 wherein the particles have a size distribution as measured by laser diffraction of d10=0.37 micrometers, D50=1.07 micrometers and D90=2.31 micrometers.
13. The method of claim 11 further including distributing the particles homogenously throughout a thickness of the coating.
14. The method of claim 1 wherein the polysiloxane filler comprises between 5 volume % to 50 volume % of the coating.
15. The method of claim 1 wherein the polysiloxane filler comprises between 25 volume % to 45 volume % of the coating.
16. The method of claim 1 wherein the polysiloxane filler comprises between 35 volume % to 45 volume % of the coating.
17. The method of claim 1 wherein the polysiloxane filler includes hydrophobic filler particles, wherein the filler particles are at least one of fibrous, flakes, platelet shaped, and spherical shaped.
18. A method for coating a part for an axially rotating machine with an erosion resilient coating, the method comprising:
providing a part of an axially rotating machine;
coating the part with a coating comprising a metal matrix having an embedded polysiloxane filler distributed throughout a thickness of the metal matrix; and
stoving the part with the coating employing a controlled process to tailor a temperature resistance and hydrophobic property of the polysiloxane filler, the controlled process employing a temperature that varies and is selected based at least in part on a required end use of the coating, a specific composition and form of the polysiloxane filler, and a presence of any catalytic substances; wherein the controlled process employs a temperature selected such that controlled partial pyrolysis results in successive replacement of carbon containing end groups with oxygen to form SiO2, yielding an increase in the ceramic (SiO2) to organic ratio of the polysiloxane filler to affect temperature resistance and hydrophobicity.