Coating material

Patent metadata

Field	Value
Publication number	US-2017002444-A1
Application number	US-201415106396-A
Country	US
Kind code	A1
Filing date	Dec 17, 2014
Priority date	Dec 20, 2013
Publication date	Jan 5, 2017
Grant date	—

Abstract

A coating material has Cr-rich regions having a Cr content >95% by mass which form Cr-containing particles. At least some of these particles are present in the form of aggregates or agglomerates, at least some have pores and have in the Cr-rich regions a mean nanohardness HIT 0.005/5/1/5 of ≦4 GPa and/or a mean surface area, measured by BET, >0.05 m 2 /g. The coating material is particularly suitable for cold gas spraying. There is also described a process for the production of a coating, and to a coating produced by the process.

First claim

1 - 28 . (canceled)

29 . A coating material, comprising:
Cr-rich regions having a Cr content >95% by mass, said Cr-rich regions forming Cr-containing particles; and wherein one or more of the following is true: at least some of said Cr-containing particles are present in the form of aggregates or agglomerates; at least some of said Cr-containing particles have pores formed therein; said Cr-rich regions have a mean nanohardness HIT 0.005/5/1/5 of ≦4 GPa; or said Cr-containing particles have a mean surface area >0.05 m2/g, measured by way of Brunauer-Emmett-Teller.

30 . The coating material according to claim 29 , configured in powder form or granulate form.

31 . The coating material according to claim 29 , wherein at least some of said Cr-containing particles have a mean porosity, determined by quantitative image analysis, of >10% by volume.

32 . The coating material according to claim 29 , which comprises a material with a lower yield strength than Cr applied to a surface of said Cr-containing particles, at least in regions thereof.

33 . The coating material according to claim 29 , wherein said Cr-containing particles have a mean particle size or granule size d50, measured by laser diffractometry, of 5 μm<d50<150 μm.

34 . The coating material according to claim 29 , comprising at least one component selected from the group consisting of hard material and lubricant.

35 . The coating material according to claim 29 , the coating material comprising at least one further metal or being a constituent of a powder mixture.

36 . The coating material according to claim 35 , wherein said powder mixture has an MCrAlY alloy composition.

37 . The coating material according to claim 29 , wherein the Cr content is >50% by mass.

38 . A process for producing a coating, the process comprising:
providing a coating material according to claim 29 ; and forming a coating with the coating material.

39 . The process according to claim 38 , which comprises reducing at least one compound from the group consisting of Cr oxide and Cr hydroxide, optionally with an added solid carbon source, while subjecting the at least compound at least temporarily to an action of hydrogen and hydrocarbon.

40 . The process according to claim 38 , which comprises forming the coating by a processes selected from the group consisting of a thermal spraying process, cold gas spraying, and a high-velocity flame spraying process.

41 . The process according to claim 38 , which comprises:
providing a process gas having a pressure of from 10 to 100 bar and a temperature between room temperature and 1400 C; accelerating the process gas in a convergent-divergent nozzle; injecting the coating material into the process gas upstream, in or downstream of the convergent-divergent nozzle; forming an adherent coating upon impact of the coating material on a substrate.

42 . The process according to claim 41 , wherein the process gas is nitrogen or a nitrogen-rich gas.

43 . A coating, comprising:
a Cr content >50% by mass; a mean thickness >20 μm; and a microstructure containing at least partially deformed Cr-containing grains; produced from a coating material according to claim 29 .

44 . The coating according to claim 43 , wherein the deformed Cr-containing grains are cold deformed.

45 . The coating according to claim 43 , wherein at least some of said grains are stretched in a direction parallel to a layer surface of the coating.

46 . The coating according to claim 45 , wherein said grains have a mean aspect ratio >1.3.

47 . The coating according to claim 43 , wherein the at least partially deformed Cr-containing grains have a mean nanohardness HIT 0.005/5/1/5 of >4 GPa.

Assignees

• Plansee Se

Inventors

• Kathrein Martin
• O'Sullivan Michael

Classifications

• B22F1/00

  Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties · CPC title

• B22F1/05

  Metallic powder characterised by the size or surface area of the particles · CPC title

• B22F1/148

  Agglomerating · CPC title

• C22C19/058

  without Mo and W · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title