NiCoCrAlY- ALLOY, A POWDER, A COATING AND A COMPONENT

Abstract

A Nickel-based alloy includes (in wt %): 25.7%-27.3% Cobalt (Co), 15.0%-16.0% Chromium (Cr), 12.2%-13.2% Aluminum (Al), 0.3%-0.5% Yttrium (Y), 2.5%-3.5% Ruthenium (Ru), 0.4%-0.8% Silicon (Si), 0.4%-0.6% Tantalum (Ta), and 0.4%-0.6% Molybdenum (Mo).

Claims

1. A Nickel-based alloy, and least comprising (in wt %), especially consisting of: Cobalt (Co) 25.7%-27.3% especially 26.5% Chromium (Cr) 15.0%-16.0% especially 15.5% Aluminum (Al) 12.2%-13.2% especially 12.7% Yttrium (Y) 0.3%-0.5% especially 0.4% Ruthenium (Ru) 2.5%-3.5% especially 3.0% optionally Molybdenum (Mo) 0.4%-0.6% especially 0.5% Silicon (Si) 0.4%-0.8% especially 0.6% Tantalum (Ta) 0.4%-0.6% especially 0.5%, optionally Sulfur (S)≤10 ppm.

2. The Alloy according to claim 1, comprising: NiCoCrAlYRu, NiCoCrAlYRuSi, NiCoCrAlYRuMo, NiCoCrAlYRuTa, NiCoCrAlYRuSiTa, NiCoCrAlYRuSiMo, NiCoCrAlYRuTaMo or NiCoCrAlYRuSiTaMo.

3. A Powder, comprising, especially consisting of, an alloy according to claim 1, optionally comprising a binder and/or ceramic particles.

4. A Coating, comprising: a composition of an alloy according to claim 1, especially having a thickness in the range of 30 μm to 800 μm.

5. A Component, comprising: a metallic substrate, especially Nickel-based or Cobalt-based superalloy, a metallic coating with a composition according to claim 1, and optionally a ceramic coating above the substrate and the metallic coating.

Description

DETAILED DESCRIPTION OF INVENTION

[0011] This invention is to solve the problem by using recent research results and upgraded thermodynamic modelling to design an optimized and innovative NiCoCrAlX alloy coatings applied by means of thermal spraying in air, vacuum, or protected atmosphere, physical deposition, and plating on Ni or Co based superalloys.

[0012] X is a combination of minor elements such as Y, Ru, Jr, Si, Hf, Ta and etc. instead of Yttrium (Y) in the current NiCoCrAlY coatings. It means that we will introduce other minor elements to replace part of Yttrium (Y) functions in order to keep Yttrium (Y) content low. Introduction of Ruthenium (Ru) and Iridium (Ir) reduces diffusion rate of Aluminum (Al) and forms diffusion barrier to minimize the interdiffusion between NiCoCrAlX coating and substrates. Ru addition increases mechanical durability of the coatings.

[0013] Moreover, another approach in designing and manufacturing the innovative NiCoCrAlX coatings is reduce S content to ≤10 ppm to further increase coating lifetime. The coating thickness should be in the range of 30-800 μm depending on type of applications and application methods.

[0014] The new NiCoCrAlX coating is Ni-based and possesses the preferred following composition (in wt %): [0015] Ni balanced, [0016] 25.7%-27.3% Cobalt (Co), [0017] 15.0%-16.0% Chromium (Cr), [0018] 12.2%-13.2% Aluminum (Al), [0019] 0.3%-0.5% Yttrium (Y), [0020] 2.5%-3.5% Ruthenium (Ru), [0021] and [0022] optionally [0023] 0.4%-0.8% Silicon (Si), [0024] 0.4%-0.6% Tantalum (Ta), [0025] 0.4%-0.6% Molybdenum (Mo).

[0026] This invention results in NiCoCrAlYRu, NiCoCrAlYRuSi, NiCoCrAlYRuTa, NiCoCrAlYRuMo, NiCoCrAlYRuSiTa, NiCoCrAlYRuSiMo, NiCoCrAlYRuTaMo, NiCoCrAlRuMoSiTa coatings with a higher temperature capacity, longer life, and larger mechanical durability than the NiCoCrAlY coatings available today.

[0027] A powder with this alloy composition can be mixed with a binder and/or refractory metals or ceramics if used as an abrasive coating.

[0028] For turbine application especially a metallic substrate like a nickel or cobalt based superalloy is used on which the inventive coating is applied on.

[0029] The coating is applied especially by the thermal spray and electron beam vapor deposition processes.

[0030] Even SLM, SLS or any AM technique is possible to apply coatings or to produce components of this alloy or used as repair material.

[0031] A layer system therefore at least comprises a metallic substrate, especially a Nickel based superalloy and at least a coating with the inventive alloy and optionally a ceramic layer on top of the metallic bond and oxidation coating.

[0032] The ceramic layer comprises preferably a Zirconia based composition, partly or fully stabilized.