METHOD FOR COATING A WALL

Abstract

A method for coating a wall with a metallic surface layer, the wall including an outer wall layer formed from or including a plastic material or a fiber composite material, the method comprising: in a first step providing a wall base body formed by the outer wall layer; therafter in a second step bonding the outer wall layer to an intermediate layer formed from or including a fiber composite material to form the wall to be coated, wherein fibers of the fiber composite material of the intermediate layer include a metallic surface, wherein fibers of the fiber composite material of the intermediate layer connected to the outer wall layer include a non-metallic fiber core coated with a metal or a metal alloy; and thereafter in a third step coating the wall with the metallic surface layer on a surface of the intermediate layer facing away from the outer wall layer.

Claims

1. A method for coating a wall with a metallic surface layer, the wall including an outer wall layer formed from or including a plastic material or a fiber composite material, the method comprising: in a first step providing a wall base body formed by the outer wall layer; therafter in a second step bonding the outer wall layer to an intermediate layer formed from or including a fiber composite material to form the wall to be coated, wherein fibers of the fiber composite material of the intermediate layer include a metallic surface, wherein fibers of the fiber composite material of the intermediate layer connected to the outer wall layer include a non-metallic fiber core coated with a metal or a metal alloy; and thereafter in a third step coating the wall with the metallic surface layer on a surface of the intermediate layer facing away from the outer wall layer by a spraying device by thermal spraying.

2. A method for coating a wall formed from a fiber composite material with a metallic surface layer, the wall including an outer wall layer formed from or including a plastic or a fiber composite material, the method comprising: in a first step applying an intermediate layer formed from a fiber composite material or including a fiber composite material or the outer wall layer to a mold body; thereafter in a second step applying the outer wall layer of the fiber composite material to the intermediate layer or applying the intermediate layer to the outer wall layer and bonding the outer wall layer to an interior of the intermediate layer to form the wall to be coated, wherein fibers of the fiber composite material of the intermediate layer include a metallic surface; thereafter in a third step curing the wall; and thereafter in a fourth step coating the wall on a surface of the intermediate layer facing away from the outer wall layer with the metallic surface layer by a spraying device by thermal spraying, wherein individual fibers of the fiber composite material of the intermediate layer applied to the mold body in the first step or applied to the outer wall layer in the second step include a non-metallic fiber core coated with a metal or a metal alloy.

3. The method according to claim 1, wherein the intermediate layer includes a fiber composite fabric or a fiber composite scrim or is formed from a fiber composite fabric or a fiber composite scrim.

4. The method according to claim 1, wherein individual fibers of the fiber composite material of the intermediate layer are coated with copper, with nickel, or with a heat-expansion-invariant alloy of metals.

5. The method according to claim 1, wherein the fiber composite material is a carbon fiber composite material, an aramid fiber composite material or a glass fiber composite material.

6. The method according to claim 1, wherein at least one of the metals aluminum, titanium, stainless steel, copper or nickel or at least one alloy of metals is applied by the thermal spray process to form the metallic surface layer.

7. The method according to claim 1, wherein the wall is formed as a laminate.

8. A wall coated according to the method according to claim 1, the wall comprising: the outer wall layer; and the intermediate layer provided on one side of the outer wall layer and bonded thereto, wherein the outer wall layer is formed from or includes the plastic material or the fiber composite material, the intermediate layer is formed from or inlcudes the fiber composite material, fibers of the fiber composite material of the intermediate layer include the metallic surface and and include the non-metallic fiber core coated with the metal or the metal alloy, the surface of the intermediate layer facing away from the outer wall layer is provided with the metallic surface layer applied by the thermal spraying.

9. The wall according to claim 8, wherein the fiber composite material of the intermediate layer includes a fiber fabric, a fiber knit or a fiber scrim or is formed from a fiber fabric, a fiber knit or a fiber scrim.

10. The wall according to claim 8, wherein the individual fibers of the fiber composite of the intermediate layer are coated with copper, with nickel or with a heat-expansion-invariant alloy of metals.

11. The wall according to claim 10, wherein the fiber composite material is a carbon fiber composite, an aramid fiber composite or a glass fiber composite.

12. The wall according to claim 8, wherein the metallic surface layer includes least one of the metals aluminum, titanium, stainless steel, copper or nickel or at least one alloy of metals or an iron-nickel alloy.

13. A method for producing a container including a container body including the wall formed according to the method according to claim 1, wherein the container body includes an opening, wherein the intermediate layer is located on an internal side of the outer wall layer facing an internal side of the container body, the method comprising: performing the coating of the wall of the container body with the metallic surface layer on the surface of the inner intermediate layer facing towards the internal side of the container body by the thermal spraying by the spraying device introduced through the opening.

14. A method for manufacturing a container including a container body formed from container parts and including an opening, the method comprising: producing the container parts of the container body, each container part including a wall formed according to the method according to claim 1, wherein the intermediate layer is arranged on on an internal side of the outer wall layer facing towards an internal side of the container body, and wherein the coating of the wall of the container parts of the container body with the metallic surface layer is performed on the surface of the inner intermediate layer facing towards the internal side of the container body; and assembling the container parts to form the container.

15. A container, comprising: a container body, including the wall according to claim 8, including the outer wall layer made from the plastic or the fiber composite material, and the inner intermediate layer formed by a fiber composite material on the internal side of the outer wall layer facing the internal side of the container body, wherein a portion of the fibers of the fiber composite material of the inner intermediate layer is coated with a metal or a metal alloy, wherein the surface of the inner intermediate layer facing the internal side of the container body is provided with a metallic surface layer applied by thermal spraying according to the method according to claim 1.

16. The method according to claim 2, wherein the intermediate layer includes a fiber composite fabric or a fiber composite scrim or is formed from a fiber composite fabric or a fiber composite scrim.

17. The method according to claim 2, wherein individual fibers of the fiber composite material of the intermediate layer are coated with copper, with nickel, or with a heat-expansion-invariant alloy of metals.

18. The method according to claim 2, wherein the fiber composite material is a carbon fiber composite material, an aramid fiber composite material or a glass fiber composite material.

19. The method according to claim 2, wherein at least one of the metals aluminum, titanium, stainless steel, copper or nickel or at least one alloy of metals is applied by the thermal spray process to form the metallic surface layer.

20. The method according to claim 2, wherein the wall is formed as a laminate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0088] The invention is now described with based on advantageous embodiment with reference to drawing figures, wherein:

[0089] FIG. 1 illustrates a partially cut container body with a wall according to the invention during the coating step according to an advantageous variant of the method according to the invention and

[0090] FIG. 2 illustrates the container body shown in section in FIG. 1 during the step of coating the wall by means of cold gas spraying.

DETAILED DESCRIPTION OF THE INVENTION

[0091] The method according to the invention for coating a wall 12 and the wall 12 according to the invention are described below by way of example using the wall 12 of a container 1, for example a pressure tank for a gaseous fuel. However, the method according to the invention and the wall according to the invention are independent of the intended use and application of the wall 12 and are not limited to the wall of a container, such as a pressure tank. In this respect, the container 1 shown here is only one of many examples having a wall constructed and coated as described below.

[0092] In FIG. 1, a container body 10 of a container 1 is shown in the phase of manufacturing the container body 10. The wall 12 of the container body 10 consists of an outer wall layer 13, which in the example shown consists of a fiber composite material with unidirectionally oriented fibers with a cross-winding, and an inner wall layer, also referred to as an intermediate layer 14, which also consists of a fiber composite material whose matrix material corresponds substantially to the matrix material of the fiber composite material of the outer wall layer 13.

[0093] To manufacture the container body 10, a mold body 2 is first provided onto which the inner wall layer 14 is applied. The inner wall layer 14 has a fiber composite material, for example a fiber composite fabric or fiber composite knitted fabric with a liquid, curable resin as matrix material, which is for example first painted or sprayed onto the mold body 2 — which is advantageously provided with a parting agent — and to which the fiber composite fabric or fiber composite knitted fabric is then applied. However, the fiber composite fabric or fiber composite knitted fabric can also be present, for example, in the form of so-called prepregs and applied to the mold body 2 in the uncured state. The wall layer, also referred to as intermediate layer 14, thus forms a closed plastic layer as a fiber composite layer enveloping the surface 2′ of the mold body 2.

[0094] As long as the intermediate layer 14 has not yet cured or has not yet fully cured, an outer wall layer 13 made of a further fiber composite material with unidirectionally oriented fibers is applied to the intermediate layer 14 forming the inner wall layer, and advantageously the mold body 2 provided with the intermediate layer 14 is wrapped with this unidirectional fiber composite material. Since the resin matrix of the fiber composite material of the outer wall layer 13 essentially corresponds to the matrix material of the intermediate layer 14 — advantageously the same resin is used here — the two wall layers 13, 14 form a close bond and ideally crosslink with each other.

[0095] In order to create access to the later hollow container body 10, a connecting flange 11 provided with a through opening 11′ can be laminated into the wall 12 of the container body 10 in the course of the production of the two wall layers 13, 14. In the example shown, such a connecting flange 11 is provided on the underside of the container body 10 shown in FIG. 1. This connecting flange can, for example, be made of a metal or also of plastic, fiber composite material or also of ceramic.

[0096] After the wall 12 has been built up over the mold body 2 in the manner described, the container body 10 is cured in a manner known per se to the skilled person. After curing, the mold body 2 is removed from the interior of the container body 10 through the opening 11′ in the connecting flange 11, for example the mold body 2 is melted out of the container body 10.

[0097] The hollow container body 10 manufactured in this way is then subjected to the coating method according to the invention shown in connection with FIG. 2, in which a surface coating 16 is applied by means of a thermal spraying method, in the example shown by means of cold gas spraying, to the inner surface 14′ of the inner wall layer forming the intermediate layer 14, i.e. to the internal side 10′ of the container body 10 facing the interior 10″ of the container 1.

[0098] In FIG. 2, the container body 10 shown in FIG. 1 is shown with the connecting flange 11 erected upwards, the container 1 being supported in a stable standing position on a base by means of supports S. The container 1 is shown in a vertical section in order to be able to show the method of coating the internal side 10′ of the container body 10.

[0099] In FIG. 2, it can be seen how the connecting flange 11, which is made of metal, for example, is laminated into the wall 12 of the container body 10 and is firmly connected to the wall 12. For example, the connecting flange 11 is anchored with its collar between the inner wall layer 14 and the outer wall layer 13 by lamination. Alternatively, however, the collar of the connecting flange 11 can also be covered on its outer side with the inner wall layer 14 and the outer wall layer 13.

[0100] Through the opening 11′ of the connecting flange 11, a spraying device 3 for a thermal spraying method is inserted from above into the interior 10″ of the container body 10. The spraying device 3 comprises a guide rod 30 which can be moved in the vertical direction by means of a control and guide mechanism (not shown), as illustrated by the double arrow V in FIG. 2, and which can be rotated about its axis X in both directions by means of the actuating and control mechanism, as symbolized by the rotation double arrow R in FIG. 2.

[0101] At the lower end of the guide rod 30 projecting into the container body 10, an injection unit 34 for the thermal spraying method is pivotably mounted by means of a swivel joint 32, which can be swiveled about a transverse axis Y at right angles to the axis X of the guide rod 30. A supply hose unit 35, which is likewise guided through the opening 11′ of the connection flange 11 into the interior 10″ of the container body 10, is functionally coupled to the injection unit 34 and connects the injection unit 34 to (not shown) supply sources for a working gas and to a supply of powdered particles, in the present case powdered metal particles, which are sprayed by the injection device 3 onto the surface 14′, facing the interior 10″, of the intermediate layer 14 on the internal side 10′ of the container body 10. For this purpose, the supply hose unit 35 has a working gas hose 35′ and a particle transport hose 35″. The injection unit 34 has at least one spray nozzle 36 through which metal material can be applied by means of a spray jet 38 to the internal side 10′ of the container body, namely to the inner surface 14′ of the intermediate layer 14 in one coating layer 18 or in several coating layers, thereby forming the surface coating 16.

[0102] In the shown example of the present invention, the injection unit 34 is a unit known per se for cold gas spraying. In the cold gas spraying method for coating surfaces, a working gas supplied to the injection unit 34 is first compressed and heated and then accelerated by expansion in the spray nozzle 36, whereby particles introduced into the gas jet, in the present case metal particles, are shot onto a, advantageously previously heated, substrate - in the present case onto the surface 14′ of the intermediate layer 14. There, the particles partially penetrate the surface 14′ to be coated and thus anchor the applied coating layer 18 of the surface coating 16 in the intermediate layer 14 forming the inner wall layer.

[0103] The layered structure of the wall 12 according to the invention with the wall base body 12′ formed by the outer wall layer 13, the intermediate layer 14 bonded to the latter and consisting of the fabric with fibers 15 with a metallic surface layer 15″ (detail B) and the coating layer 18 applied to the intermediate layer 14 by means of cold gas spraying and forming the surface coating 16 can be clearly seen in the enlarged representation of detail A in FIG. 2.

[0104] Detail B in FIG. 2 shows an enlarged view of a partially cut top view of the intermediate layer 14 in the direction of the arrow B. The surface 14′ of the intermediate layer 14 is predominantly formed by the resin matrix covering the fibers 15 of the fiber composite of the intermediate layer 14, shown here as a fabric. The individual fibers 15 have a fiber core 15′, for example of carbon fiber, aramid fiber or glass fiber material, which is coated, for example vapor-deposited, with a metal on its surface, so that the individual fibers of the woven (or knitted) fabric of the intermediate layer 14 are provided with a metallic surface layer 15″. Advantageously, the metallic surface layer 15″ is made of copper or nickel or of a metal alloy which is advantageously heat expansion invariant. Such a thermal expansion invariant iron-nickel alloy is known, for example, under the proprietary trade name Invar®.

[0105] As can be seen in FIG. 2, in the example shown, just under the upper half of the container body 10 including the inner surface 11″ of the connecting flange 11 facing the interior 10″ (or the part of the intermediate layer 14 lying thereon) has already been coated by the spraying device 3 with the surface coating 16 from the metal particles supplied. The surface coating 16 thus also covers the so-called shank area of the connecting flange 11. The metal particles applied by means of cold gas spraying form a closed, homogeneous surface coating 16 which in the finished state — even if the lower part of the container body 10 will still be provided with the surface coating 16 —surrounds the interior 10″ of the container body 10 (except for the opening 11′ in the connecting flange 11).

[0106] Due to the rotatability of the spraying device 3 about the vertical axis X corresponding to the rotation double arrow R, the vertical displaceability of the spraying device 3 corresponding to the double arrow V and the swiveling of the spraying unit 34 about the transverse axis Y, the nozzle 36 can be directed to any location of the internal side 10′ of the container body′ so that the internal side 10′ of the container body′ 10 can be coated without gaps by means of the thermal spraying method, i.e. in this case cold gas spraying, and thus forms a closed and gas-tight surface coating 16.

[0107] The surface coating 16 may comprise a single layer applied once, or a plurality of successively applied layers of the same metal material or of different metal materials.

[0108] If the container is provided with at least one inner bulkhead which divides the interior of the container into two (or more) separate compartments (for example to accommodate different fuel components), this bulkhead, which consists for example of a glass fiber composite material or carbon fiber composite material, is also provided with a metallic surface coating on at least one of its surfaces (advantageously on both surfaces) by the method according to the invention. As a result, both spaces inside the container are completely provided with the metallic surface coating on all surfaces of their respective internal sides.

[0109] The application of the method is particularly advantageous if the container body is made in one piece. The wall of the container body can be manufactured first, if necessary, already with connecting flanges, and then the metallic surface coating can be sprayed onto the internal side of the wall of the container.

[0110] However, the method can also be used if the container body is made up of several parts. In this case, the individual container parts, i.e., individual walls, are first manufactured and the respective surface coating is sprayed onto their respective internal sides, and then the container parts (walls) are assembled to form a container.

[0111] Reference signs in the description and the drawings serve only for a better understanding of the invention and do limit the scope of the invention which is defined in the appended patent claims.

TABLE-US-00001 REFERENCE NUMERALS AND DESIGNATIONS 1 container 2 mold body 2′ surface of the mold body 3 spraying device 10 container body 10 ′ internal side of the container body 10 ″ interior 11 connection flange 11′ opening 11 ″ inner surface 12 wall 12′ wall base body 13 wall layer 13′ internal side 14 intermediate layer 14′ surface 15 intermediate layer fiber 15′ fiber core (e.g., carbon fiber, aramid fiber, glass fiber) 15 ″ metallic surface layer of the fiber 16 surface coating 18 coating layer 30 bar 32 pivot joint 34 injection unit 35 supply hose unit 35′ working gas hose 35″ particle transport hose 36 spray nozzle 38 spray jet 110 vessel body R rotation double arrow S supports V double arrow X vertical axis Y transverse axis