COMPONENT FOR A HOT DIP COATING SYSTEM AND METHOD FOR THE PRODUCTION THEREOF

Abstract

A component for a hot dip coating system, which comes into direct contact with an immersion bath of liquid metal during operation of the hot dip coating system, having a metallic base body, wherein at least one portion of a surface of the base body is provided with a three-layered coating, which includes a corrosion-resistant bonding layer arranged directly on the surface portion, a barrier layer arranged on the bonding layer, and a ceramic surface layer arranged on the barrier layer.

Claims

1-12. (canceled)

13. A component for a hot-dip coating system, which component comes into direct contact with an immersion bath containing liquid metal during operation of the hot-dip coating system, comprising: a metallic base body; and a three-layer coating on at least a portion of a surface of the base body, the three-layer coating comprising a corrosion-resistant bonding layer arranged directly on the surface of the portion in question, the bonding layer being made at least partially from an iron, nickel, cobalt, or nickel-cobalt base alloy, a barrier layer arranged on the bonding layer, the barrier layer being made at least partially from molybdenum, a molybdenum containing alloy, or molybdenum carbide, and a ceramic surface layer arranged on the barrier layer, the surface layer being made at least partially from an oxide ceramic containing rare earths.

14. The component according to claim 13, wherein the component is a roller for guiding or deflecting a metal strip to be coated as the metal strip is being guided through the immersion bath.

15. The component according to claim 14, wherein the base body comprises a roller portion and two axial bearing journals connected to the roller portion and arranged coaxially to the roller portion, wherein at least parts of surfaces of each of the bearing journals are provided with the three-layer coating, and wherein a lateral surface of the roller portion is provided with a metallic protective layer.

16. The component according to claim 14, wherein the base body comprises a roller portion and two axial bearing journals connected to the roller portion and arranged coaxially to the roller portion, wherein a metal bushing is installed on each of the bearing journals.

17. A method for producing a component for a hot-dip coating system, which component comes into direct contact with an immersion bath containing liquid metal during operation of the hot-dip coating system, the method comprising the steps of: providing a metallic base body; applying a corrosion-resistant bonding layer made at least partially from an iron, nickel, cobalt, or nickel-cobalt base alloy to at least part of a surface of the base body; applying a barrier layer made at least partially from molybdenum, a molybdenum containing alloy, or molybdenum carbide to the bonding layer; and applying a ceramic surface layer made at least partially from an oxide ceramic containing rare earths to the barrier layer, the layers forming a three-layer coating.

18. The method according to claim 17, wherein the bonding layer and the barrier layer are each applied by thermal or kinetic spraying.

19. The method according to claim 17, wherein the surface layer is applied by thermal spraying.

20. The method according to claim 17, wherein the base body has a roller portion and two axial bearing journals connected to the roller portion and arranged coaxially to the roller portion, the three-layer coating being applied to at least parts of surfaces of each of the bearing journals, the method further including applying a metallic protective layer to a lateral surface of the roller section.

21. The method according to claim 17, wherein the base body has a roller portion and two axial bearing journals connected to the roller portion and arranged coaxially to the roller portion, the method further including installing a metal bushing on each of the bearing journals.

Description

[0028] In the following, the invention is explained in greater detail with reference to the attached figures, which illustrate preferred embodiments, wherein the features explained below can represent an aspect of the invention either alone or in various combinations with each other:

[0029] FIG. 1 shows a schematic diagram in the form of a longitudinal cross section of an exemplary embodiment of a component according to the invention in the form of a roller;

[0030] FIG. 2 shows a schematic diagram in the form of a longitudinal cross section of another exemplary embodiment of a component according to the invention in the form of a roller; and

[0031] FIG. 3 shows a schematic diagram in the form of a longitudinal cross section of another exemplary embodiment of a component according to the invention in the form of a roller.

[0032] FIG. 1 shows a schematic diagram in the form of a longitudinal cross section of an exemplary embodiment of a component 1 according to the invention for a hot-dip coating system (not shown), wherein the component 1 comes into direct contact with an immersion bath containing liquid metal during operation of the hot-dip coating system. The component 1 is configured as a roller for guiding or deflecting a metal strip to be coated as it is guided through the immersion bath.

[0033] The component 1 comprises a metallic base body 2, which has a roller portion 3 and two axial bearing journals 4, which are connected to the roller portion 3 and arranged coaxial to it. The roller portion 3 of the base body 2 is provided with a three-layer coating 5, which comprises a corrosion-resistant bonding layer 6, arranged directly on the surface of the roller portion 3; a barrier layer 7 arranged on the bonding layer 6; and a ceramic surface layer 8 arranged on the barrier layer 7. The bonding layer 6 is made at least partially from an iron, nickel, cobalt, or nickel-cobalt base alloy. The barrier layer 7 is made at least partially from a transition metal or an alloy of transition metals. The surface layer 8 is made at least partially from a pure oxide ceramic or an oxide ceramic provided with rare earths.

[0034] FIG. 2 shows a schematic diagram in the form of a longitudinal cross section of another exemplary embodiment of a component 10 according to the invention for a hot-dip coating system (not shown), wherein the component 10 comes into direct contact with an immersion bath containing liquid metal during operation of the hot-dip coating system. The component 10 is configured as a roller for guiding or deflecting a metal strip to be coated as it is guided through the immersion bath.

[0035] The component 10 comprises a metallic base body 12, which has a roller portion 13 and two axial bearing journals 14, which are connected to the roller portion 13 and arranged axially to it. The surfaces of each of the bearing journals 14 are provided with the three-layer coating 5, which comprises a corrosion-resistant bonding layer arranged directly on the surface of the roller portion 13, a barrier layer arranged on the bonding layer 6; and a ceramic surface layer 8 arranged on the barrier layer 7. The bonding layer is made at least partially from an iron, nickel, cobalt, or nickel-cobalt base alloy. The barrier layer 7 is made at least partially from a transition metal or an alloy of transition metals. The surface layer 8 is made at least partially from a pure oxide ceramic or an oxide ceramic provided with rare earths. The lateral surface of the roller part 13 is provided with a metallic protective layer 11, which is made at least partially from molybdenum, a molybdenum-containing alloy, or molybdenum carbide.

[0036] FIG. 3 shows a schematic diagram in the form of a longitudinal cross section of another exemplary embodiment of a component 20 according to the invention for a hot-dip coating system, wherein the component 20 comes into direct contact with an immersion bath containing liquid metal during operation of the hot-dip coating system. The component 20 is configured as a roller for guiding or deflecting a metal strip to be coated as it is being guided through the immersion bath.

[0037] The component 20 differs from the exemplary embodiment shown in FIG. 1 in that a metal bushing 21 is installed on each of the bearing journals 4. The metal bushings can be made of carbon steels such as C45, C60, or C70, or of case-hardening/heat-treatable steels such as 42CrMo4. To avoid repetition, reference can be made here to the description of FIG. 1 given above.

LIST OF REFERENCE NUMBERS

[0038] 1 component [0039] 2 base body [0040] 3 roller portion [0041] 4 bearing journal [0042] 5 three-layer coating [0043] 6 bonding layer [0044] 7 barrier layer [0045] 8 surface layer [0046] 10 component [0047] 11 metallic protective layer [0048] 12 base body [0049] 13 roller portion [0050] 14 bearing journal [0051] 15 component [0052] 21 metal bushing