Coated metal strip

• US 5,491,035 A
• Filed: 11/30/1994
• Issued: 02/13/1996
• Est. Priority Date: 03/27/1992
• Status: Expired due to Term

• Current Assignee: Revere Copper Products, Inc.
• Original Assignee: The Louis Berkman Company
• Inventors: Zamanzadeh, Mehrooz, Carey, Jay F. II
• Primary Examiner(s): Zimmerman, John
• Application Number:
  US08/347,261
• Time in Patent Office: 440 Days
• Field of Search: 426/648, 426/659, 426/679, 426/685, 426/646, 426/647, 426/658, 426/939
• US Class Current: 428/647
• CPC Class Codes: B32B 15/18 comprising iron or steel B32B15/011, B32B15/012 and B32B15/013 take precedence
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: C22C 13/00 Alloys based on tin
• CPC Class Codes: C22C 18/00 Alloys based on zinc
• CPC Class Codes: C23C 2/00 Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
• CPC Class Codes: C23C 2/02 Pretreatment of the material to be coated, e.g. for coating on selected surface areas C23C2/30 takes precedence
• CPC Class Codes: C23C 2/06 Zinc or cadmium or alloys based thereon
• CPC Class Codes: C23C 2/08 Tin or alloys based thereon
• CPC Class Codes: C23C 2/26 After-treatment C23C2/14 takes precedence
• CPC Class Codes: C23C 28/025 with at least one zinc-based layer
• CPC Class Codes: C25D 3/60 containing more than 50% by weight of tin
• CPC Class Codes: C25D 5/10 Electroplating with more than one layer of the same or of different metals for bearings C25D7/10
• CPC Class Codes: Y10S 428/939 Molten or fused coating
• CPC Class Codes: Y10T 428/12715 Next to Group IB metal-base component
• CPC Class Codes: Y10T 428/12722 Next to Group VIII metal-base component
• CPC Class Codes: Y10T 428/12792 Zn-base component
• CPC Class Codes: Y10T 428/12799 Next to Fe-base component [e.g., galvanized]
• CPC Class Codes: Y10T 428/12979 Containing more than 10% nonferrous elements [e.g., high alloy, stainless]

Abstract

A corrosion-resistant architectural material which is essentially lead free and is not highly reflective. The coating on the material is a two-phase metallic coating comprised of zinc and tin. The tin-zinc coating may also include aluminum, antimony, bismuth, copper, magnesium, nickel and/or titanium to improve the coating process and/or improve the properties of the tin-zinc coating.

Claims

1. A coated metal strip including a base metal strip selected from the group consisting of carbon steel, stainless steel and copper, said base metal strip having parallel surfaces both of which are coated in a continuous, hot-dip process by continuously passing the continuous base metal strip through a bath of molten tin-zinc alloy at an essentially constant speed to deposit onto said base strip an impervious low reflecting, corrosive-resistant, two-phase layer of said tin-zinc alloy, said two-phase tin-zinc layer comprising tin, at least about 20 weight percent zinc and an effective amount of a metal stabilizer selected from the group consisting of copper, antimony, bismuth and mixtures thereof, said two-phase tin-zinc layer having a tin plus a zinc content at least 75 weight percent of said layer.

2. A coated metal strip as defined in claim 1, wherein said coating comprises:

space="preserve" listing-type="tabular">______________________________________ Tin [20-93] 20-80 Zinc [7-80] 20-80 Magnesium 0.0-5.0 Nickel 0.0-5.0 Copper 0.0-5.0 Titanium 0.0-1.0 Aluminum 0.0-5.0 Antimony 0.0-5.5 Bismuth 0.0-1.5. ______________________________________

3. A coated metal strip as defined in claim 2, wherein said tin-zinc coating comprises:

space="preserve" listing-type="tabular">______________________________________ Tin [20-93] 20-80 Zinc [7-80] 20-80 Magnesium ≦

0.4 Nickel ≦

1.0 Copper ≦

2.7 Aluminum ≦

0.5 Titanium ≦

0.15 Antimony ≦

5.5 Bismuth ≦

1.7. ______________________________________

4. A coated metal strip as defined in claim 3, wherein said tin-zinc coating comprises:

space="preserve" listing-type="tabular">______________________________________ Tin [20-93] 20-80 Zinc [7-80] 20-80 Magnesium ≦

0.4 Nickel ≦

0.7 Copper ≦

1.0 Aluminum ≦

0.3 Titanium ≦

0.15 Antimony ≦

1.0 Bismuth ≦

1.7. ______________________________________

5. A coated metal strip as defined in claim 1, wherein the thickness of said tin-zinc coating is at least 0.0003 inch.

6. A coated metal strip as defined in claim 1, wherein the lead content of said tin-zinc coating is not more than 0.01 weight percent.

7. A coated metal strip as defined in claim 1, wherein a nickel layer is applied to said metal material prior to applying said tin-zinc coating.

8. A coated metal strip as defined in claim 1, wherein said tin-zinc coating includes magnesium.

9. A coated metal strip as defined in claim 8, wherein said tin-zinc coating includes aluminum.

10. A coated metal strip defined in claim 8, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

11. A coated metal strip as defined in claim 10, wherein said tin-zinc coating includes aluminum.

12. A coated metal strip as defined in claim 1, wherein said metal strip is a metal selected from the group consisting of carbon steel, stainless steel and copper.

13. A coated metal strip as defined in claim 1, wherein the content of said metallic stabilizer in said tin-zinc coating is at least 0.05 weight percent.

14. A coated metal strip as defined in claim 13, wherein the content of said bismuth in said tin-zinc coating is less than about 1.7 weight percent.

15. A coated metal strip as defined in claim 14, wherein the antimony content of said tin-zinc coating is less than about 5.5 weight percent.

16. A coated metal strip as defined in claim 13, wherein the antimony content of said tin-zinc coating is less than about 5.5 weight percent.

17. A coated metal strip as defined in claim 16, wherein said antimony content of said tin-zinc coating is about 1.0 weight percent.

18. A coated metal strip as defined in claim 1, wherein said tin-zinc coating includes titanium.

19. A coated metal strip as defined in claim 18, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

20. A coated metal strip as defined in claim 19, wherein said titanium content of said tin-zinc coating is 0.01 to about 0.15 weight percent.

21. A coated metal strip as defined in claim 18, wherein said tin-zinc coating includes aluminum.

22. A coated metal strip as defined in claim 1, wherein said tin-zinc coating includes aluminum.

23. A coated metal strip as defined in claim 22, wherein the aluminum content of said tin-zinc coating is at least 0.01 weight percent.

24. A coated metal strip as defined in claim 23, wherein said aluminum content of said tin-zinc coating is less than about 0.5 weight percent.

25. A coated metal strip as defined in claim 24, wherein said aluminum content of said tin-zinc coating is about 0.3 weight percent.

26. A coated metal strip including a base metal strip with parallel surfaces both of which are coated in a continuous, hot-dip process by continuously passing the continuous base metal strip through a bath of molten tin-zinc alloy at an essentially constant speed to deposit onto said base strip an impervious low reflecting, corrosive-resistant, two-phase layer of said tin-zinc alloy, said two-phase tin-zinc layer comprising tin, at least 20 weight percent zinc and a metal additive including a metal selected from the group consisting of magnesium, copper, titanium, antimony, bismuth and mixtures thereof, said two-phase tin-zinc layer having a tin plus a zinc content at least 75 weight percent of said layer, and said nickel content of said tin-zinc coating is at least 0.3 weight percent.

27. A coated metal strip as defined in claim 26, wherein said nickel content of said tin-zinc coating is 0.3-0.9 weight percent.

28. A coated metal strip as defined in claim 27, wherein said nickel content of said tin-zinc coating is about 0.7 weight percent.

29. A coated metal strip as defined in claim 26, wherein said tin-zinc coating includes copper.

30. A coated metal strip as defined in claim 29, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

31. A coated metal strip as defined in claim 30, wherein said tin-zinc coating includes aluminum.

32. A coated metal strip as defined in claim 26, wherein said tin-zinc coating includes magnesium.

33. A coated metal strip as defined in claim 32, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

34. A coated metal strip as defined in claim 33, wherein said tin-zinc coating includes aluminum.

35. A coated metal strip as defined in claim 26, wherein said lead content of said tin-zinc coating is not more than 0.01 weight percent.

36. A coated metal strip as defined in claim 35, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

37. A coated metal strip as defined in claim 36, wherein said tin-zinc coating includes aluminum.

38. A coated metal strip as defined in claim 26, wherein said tin-zinc coating includes a metallic stabilizer selected from the group consisting of antimony and bismuth.

39. A coated metal strip as defined in claim 38, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

40. A coated metal strip as defined in claim 39, wherein said tin-zinc coating includes aluminum.

41. A coated metal strip as defined in claim 26, wherein said tin-zinc coating includes titanium.

42. A coated metal strip as defined in claim 41, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

43. A coated metal strip as defined in claim 41, wherein said tin-zinc coating includes aluminum.

44. A coated metal strip as defined in claim 26, wherein said tin-zinc coating includes aluminum.

45. A coated metal strip including a base metal strip with parallel surfaces both of which are coated in a continuous, hot-dip process by continuously passing the continuous base metal strip through a bath of molten tin-zinc alloy at an essentially constant speed to deposit onto said base strip an impervious low reflecting, corrosive-resistant, two-phase layer of said tin-zinc alloy, said two-phase tin-zinc layer comprising tin, zinc and a metal additive including a metal selected from the group consisting of magnesium, copper, titanium, antimony, bismuth and mixtures thereof, said two-phase tin-zinc layer having a tin plus a zinc content at least 75 weight percent of said layer and said copper content of said tin-zinc coating is at least 0.1 weight percent.

46. A coated metal strip as defined in claim 45, wherein said copper content of said tin-zinc coating is 0.1-2.7 weight percent.

47. A coated metal strip as defined in claim 46, wherein said copper content of said tin-zinc coating is about 1.0 weight percent.

48. A coated metal strip as defined in claim 45, wherein said tin-zinc coating includes magnesium.

49. A coated metal strip as defined in claim 48, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

50. A coated metal strip as defined in claim 49, wherein said tin-zinc coating includes aluminum.

51. A coated metal strip as defined in claim 45, wherein said tin-zinc coating includes a metallic stabilizer selected from the group consisting of antimony and bismuth.

52. A coated metal strip as defined in claim 51, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

53. A coated metal strip as defined in claim 52, wherein said tin-zinc coating includes aluminum.

54. A coated metal strip as defined in claim 45, wherein said tin-zinc coating includes titanium.

55. A coated metal strip as defined in claim 54, wherein said tin-zinc coating includes 0.1-1.0 weight percent titanium.

56. A coated metal strip as defined in claim 54, wherein said tin-zinc coating includes aluminum.

57. A coated metal strip as defined in claim 45, wherein said tin-zinc coating includes aluminum.

58. A metal strip coated in a continuous, hot-dip process having a coating with a low reflecting, corrosive-resistant, two-phase tin-zinc metallic coating, said coating comprising tin and zinc wherein the tin plus zinc content is at least 75 weight percent of said coating, said tin-zinc coating including at least one metal selected from the group consisting of magnesium, nickel, copper, titanium, aluminum, antimony, bismuth, and mixtures thereof, wherein the magnesium content of said tin-zinc coating is at least 0.01 weight percent.

59. A coated metal strip as defined in claim 58, wherein said magnesium content of said tin-zinc coating is 0.01-1.0 weight percent.

60. A coated metal strip as defined in claim 58, wherein said tin-zinc coating includes a metallic stabilizer selected from the group consisting of antimony and bismuth.

61. A coated metal strip as defined in claim 58, wherein said tin-zinc coating includes titanium.

62. A coated metal strip as defined in claim 61, wherein said tin-zinc coating includes 0.01-1.0 weight percent titanium.

63. A coated metal strip as defined in claim 58, wherein said tin-zinc coating includes aluminum.

64. A metal strip coated in a continuous, hot-dip process having a coating with a low reflecting, corrosive-resistant, two-phase tin-zinc metallic coating, said coating comprising tin and zinc wherein the tin plus zinc content is at least 75 weight percent of said coating, said tin-zinc coating including at least one metal selected from the group consisting of magnesium, nickel, copper, titanium, aluminum, antimony, bismuth and mixtures thereof, wherein said magnesium content of said tin-zinc coating is 0.01 to about 0.4 weight percent.

65. A coated metal strip formed of a given metal, said metal strip having a thickness of less than about 0.10 inch and exposed surfaces supplied from a coil of said metal strip and coated with a highly corrosive-resistant, two-phase tin-zinc alloy by continuously passing said continuous metal strip through a molten bath of said tin-zinc coating alloy to deposit an impervious layer of said tin-zinc coating alloy having a thickness in the range of 0.0003 to 0.050 inch onto the exposed surfaces of said moving strip by a continuous hot dip procedure to produce an intermetallic interface comprising an interface multi-phase alloy constituting a heat created mixture of said given metal and said coating alloy, said interface alloy bonding said impervious layer to said exposed surfaces, said tin-zinc coating alloy including at least about 20 percent by weight tin and at least about 20 weight percent zinc wherein said tin content plus the zinc content exceeds 75 percent by weight of said coating alloy, said coating alloy also including a metal agent selected from the group consisting of an effective amount of metallic stabilizer selected from the group consisting of antimony, bismuth, copper and mixtures thereof;

an effective amount of corrosion resistant additive selected from the group consisting of copper, magnesium, nickel and mixtures thereof.

66. A coated metal strip as defined in claim 65, wherein said given metal is ferrous.

67. A coated metal strip as defined in claim 65, wherein said given metal is stainless steel including chromium in said given metal.

68. A coated metal strip as defined in claim 65, wherein said given metal is copper.

69. A coated metal strip as defined in claim 65, wherein base metal is an alloy of iron with an alloying metal selected from the group consisting of chromium, nickel, carbon, molybdenum, silicon, manganese, titanium, boron, copper, aluminum and mixtures thereof.

70. A coated metal strip as defined in claim 65, wherein said coating alloy includes at least 0.1-5.0 percent by weight of copper.

71. A coated metal strip as defined in claim 65, wherein said coating alloy includes at least 0.01-5.0 percent by weight of aluminum.

72. A coated strip as defined in claim 71, wherein said two-phase coating alloy includes copper.

73. A coated strip as defined in claim 71, wherein said two-phase coating alloy includes magnesium.

74. A coated strip as defined in claim 71, wherein said two-phase coating alloy includes nickel.

75. A coated metal strip as defined in claim 65, wherein said coating alloy includes at least 0.3-5.0 percent by weight of nickel.

76. A coated metal strip as defined in claim 65, wherein said coating alloy includes 0.01-5.0 percent by weight titanium.

77. A coated metal strip as defined in claim 65, wherein said coating alloy includes at least 0.05 percent by weight of a metallic stabilizer.

78. A coated strip as in claim 65, wherein said continuously passing said continuous metal strip through a molten bath of said tin-zinc alloy has an operation line speed of less than 150 feet/minute.

79. A coated metal strip formed of a given metal, said metal strip having a thickness of less than about 0.10 inch and exposed surfaces supplied from a coil of said metal strip and coated with a highly corrosive-resistant, two-phase tin-zinc alloy by continuously passing said continuous metal strip through a molten bath of said tin-zinc coating alloy to deposit an impervious layer of said tin-zinc coating alloy having a thickness in the range of 0.0003 to 0.050 inch onto the exposed surfaces of said moving strip by a continuous hot dip procedure to produce an intermetallic interface comprising an interface multi-phase alloy constituting a heat created mixture of said given metal and said coating alloy, said interface alloy bonding said impervious layer to said exposed surfaces, said tin-zinc coating alloy including at least 15 percent by weight tin wherein said tin content plus the zinc content exceeds 75 percent by weight of said coating alloy, said tin-zinc coating alloy includes a metal selected from the group consisting of aluminum, antimony, bismuth, copper, magnesium, titanium and mixtures thereof, wherein said coating alloy includes 0.01-5.0 percent by weight magnesium.