NICKEL-CHROMIUM NANOLAMINATE COATING HAVING HIGH HARDNESS

• US 20190309430A1
• Filed: 11/14/2018
• Published: 10/10/2019
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Modumetal Incorporated
• Original Assignee: Modumetal Incorporated
• Inventors: Sklar, Glenn
• Granted Patent: US 10,844,504 B2
• Time in Patent Office: Days
• CPC Class Codes: B32B 15/01 all layers being exclusively metallic making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00
• CPC Class Codes: C25D 1/00 Electroforming
• CPC Class Codes: C25D 3/06 from solutions of trivalent chromium
• CPC Class Codes: C25D 3/12 of nickel or cobalt
• CPC Class Codes: C25D 3/20 of iron
• CPC Class Codes: C25D 3/38 of copper
• CPC Class Codes: C25D 3/54 of metals not provided for in groups C25D3/04 - C25D3/50
• CPC Class Codes: C25D 3/562 containing more than 50% by weight of iron or nickel or cobalt
• CPC Class Codes: C25D 5/14 two or more layers being of nickel or chromium, e.g. duplex or triplex layers
• CPC Class Codes: C25D 5/18 Electroplating using modulated, pulsed or reversing current
• CPC Class Codes: C25D 5/34 Pretreatment of metallic surfaces to be electroplated
• CPC Class Codes: C25D 5/36 of iron or steel
• CPC Class Codes: C25D 5/611 Smooth layers
• CPC Class Codes: C25D 5/623 Porosity of the layers
• CPC Class Codes: C25D 5/627 Electroplating characterised by the visual appearance of the layers, e.g. colour, brightness or mat appearance
• CPC Class Codes: C25D 9/04 with inorganic materials

Abstract

The present disclosure describes electrodeposited nanolaminate materials having layers comprised of nickel and/or chromium with high hardness. The uniform appearance, chemical resistance, and high hardness of the nanolaminate NiCr materials described herein render them useful for a variety of purposes including wear (abrasion) resistant barrier coatings for use both in decorative as well as demanding physical, structural and chemical environments.

Claims

1. A process for forming a multilayered coating on a surface of an object by electrodeposition, the process comprising:

(a) providing one or more electrolyte solutions comprising a nickel salt and/or a chromium salt;

(b) providing the object for electrodeposition;

(c) contacting at least a portion of the surface of the object with one of said one or more electrolyte solutions;

(d) passing a first electric current through the object to deposit a first layer comprising a first nickel-chromium alloy comprising greater than about 92% nickel and at least 0.1% chromium, by weight, on the object;

(e) passing a second electric current through the object to deposit a second layer comprising a second nickel-chromium alloy comprising about 14% to about 40% chromium and at least 0.1% nickel, by weight, on the surface; and

(f) repeating steps (d) and (e) two or more times, thereby producing the multilayered coating comprising alternating first layers of the first nickel-chromium alloy and second layers of the second nickel-chromium alloy on at least the portion of the surface of the object.

3. The process of claim 1, wherein at least one of the one or more electrolyte solutions is an aqueous solution comprising one or more complexing agents.

6. The process of claim 1, wherein the first electric current ranges from approximately 10 mA/cm² to approximately 100 mA/cm², and the second electric current ranges from approximately 100 mA/cm² to approximately 500 mA/cm².

8. The process of claim 1, wherein the first electric current is applied to the object in pulses ranging from approximately 0.001 second to approximately 1.00 second, and the second electric current is applied to the object in pulses ranging from approximately 0.001 second to approximately 1.00 seconds.

12. The process of claim 1, wherein the first layer has a thickness ranging from about 25 nanometers to about 75 nanometers, and the second layer has a thickness ranging from about 125 nanometers to about 175 nanometers.

16. The process of claim 1, wherein the first layers comprise at least about 95% nickel, by weight, and the balance of the first layers is chromium.

17. The process of claim 1, wherein the second layers comprise about 14% to about 21% chromium, by weight, and the balance of the second layers is nickel.

20. The process of claim 1, wherein the multilayered coating comprises at least fifty alternating first layers and second layers.

43. The process of claim 1, further comprising separating the object from the multilayered coating.

2. (canceled)

4-5. -5. (canceled)

7. (canceled)

9-11. -11. (canceled)

13-15. -15. (canceled)

18-19. -19. (canceled)

21. (canceled)

22. An object comprising:

a multilayered coating on at least a portion of a surface of a substrate, the multilayered coating comprising a plurality of alternating first layers of a first nickel-chromium alloy comprising greater than about 92% nickel and at least 0.1% chromium, by weight, and second layers of a second nickel-chromium alloy comprising at least 0.1% nickel and about 14% to about 40% chromium, by weight.

23. The object of claim 22 comprising at least 100 alternating first and second layers.

24. The object of claim 22, wherein the first layers have a thickness ranging from about 25 nanometers to about 75 nanometers, and the second layers have a thickness ranging from about 125 nanometers to about 175 nanometers.

30. The object of claim 22, wherein the first layers comprise greater than about 92% nickel, by weight and the balance of the first layers is chromium.

31. The object of claim 22, wherein the second layers comprise about 14% to about-21%, chromium, by weight and the balance of the second layers is nickel.

32. The object of claim 22, wherein the first layers, the second layers, or both comprise at least one element selected independently from the group consisting of carbon, cobalt, copper, iron, indium, manganese, niobium, tungsten, molybdenum, and phosphorus.

35. The object of claim 22, wherein the multilayered coating has a Vickers microhardness as measured by ASTM E384-11e1 of 550-750 without heat treatment.

37. The object or coating of claim 22, wherein the substrate comprises one or more metals or other elements selected from the group consisting of C, Co, Cu, Fe, In, Mn, Nb, W, Mo, and P.

41. The object of claim 22, wherein the multilayered coating has a Vickers microhardness as measured by ASTM E384-11e1 of 550-750 without heat treatment.

44. The object of claim 22, further comprising a nickel strike layer between the surface of the object and the multilayered coating.

25-29. -29. (canceled)

33-34. -34. (canceled)

36. (canceled)

38-40. -40. (canceled)

42. (canceled)

45. A method for forming a multilayered coating on an object, the method comprising:

(a) forming a first layer on a conductive surface of the object by contacting the conductive surface with an electrolyte solution comprising a nickel salt and a chromium salt and passing a first electric current through the object, the first layer comprising a first nickel-chromium alloy comprising greater than about 92% nickel and at least about 0.1% chromium, by weight;

(b) forming a second layer on the first layer by contacting the first layer with the electrolyte solution and passing a second electric current through the object, the second layer comprising a second nickel-chromium alloy comprising at least about 0.1% nickel and about 14% to about 40% chromium, by weight; and

(c) producing the multilayered coating by repeating steps (a) and (b) two or more times, the multilayered coating having at least four layers comprising the first layer and the second layer in an alternating pattern.

46. The method of claim 45, further comprising a strike layer between the conductive surface of the object and the multilayered coating.

47. The method of claim 45, wherein the first layer, the second layer, or both comprise at least one element selected independently from the group consisting of carbon, cobalt, copper, iron, indium, manganese, niobium, tungsten, molybdenum, and phosphorus.