Aluminium Alloy Strip for Adhesive Connection

Patent metadata

Field	Value
Publication number	US-2018347067-A1
Application number	US-201816046575-A
Country	US
Kind code	A1
Filing date	Jul 26, 2018
Priority date	Jan 27, 2016
Publication date	Dec 6, 2018
Grant date	—

Abstract

The invention relates to a strip consisting of an aluminium alloy for providing adhesive connections. In addition, the invention relates to a method for producing a strip having a one or two-sided surface structure which consists of an aluminium alloy, at least provided in certain areas and prepared for an adhesive connection, and also relates to a corresponding adhesive connection. The object of providing an aluminium alloy strip optimised for adhesive connections, which has optimised surface properties for ageing-resistant adhesive connections, on the one hand, and which can be cost-effectively produced in a way which is reliable in terms of the process, on the other hand, is achieved for a strip consisting of an aluminium alloy for providing adhesive connections by the strip at least in areas having a surface structure prepared for adhesive connections, wherein the surface structure has depressions which were produced using an electrochemical graining process.

First claim

1 . Use of a strip consisting of an aluminium alloy for providing adhesive connections, in particular adhesive connections in motor vehicles, wherein the strip at least in certain areas has a surface structure prepared for an adhesive connection, wherein the surface structure has depressions which were produced using an electrochemical graining process, wherein the surface structure which is at least provided in certain areas is provided on at least one or on both sides of the strip and has a reduced valley depth S vk of 1.0 μm to 6.0 μm.

2 . Use of a strip according to claim 1 ,
wherein the strip at least partly consists of an aluminium alloy of the type AA7xxx, type AA6xxx, type AA5xxx or of the type AA3xxx, in particular AA7020, AA7021, AA7108, AA6111, AA6060, AA6014, AA6016, AA6005C, AA6451, AA5454, AA5754, AA5182, AA5251 or AlMg6, AA3104, AA3103.

3 . Use of a strip according to claim 1 ,
wherein the strip is designed for producing sheets for motor vehicles, in particular for producing sheets for structural applications of motor vehicles.

4 . Use of a strip according to claim 1 ,
wherein the surface structure which is at least provided in certain areas is provided on at least one or on both sides of the strip and has a reduced valley depth S vk of 1.5 μm to 4.0 μm, particularly preferably 2.2 μm to 4.0 μm.

5 . Use of a strip according to claim 1 ,
wherein the strip has the state soft-annealed (“O”) or solution-annealed and quenched (“T4”).

6 . Use of a strip according to claim 1 ,
wherein the strip or sheet has a passivation layer which is applied after the electrochemical graining.

7 . Use of a strip according to claim 1 ,
wherein the average roughness of the surface S a is 0.7 μm to 1.5 μm, preferably 0.7 μm to 1.3 μm or preferably 0.8 μm to 1.2 μm.

8 . Use of a strip according to claim 3 for producing one or more sheets by cutting the strip to size.

9 . Method for producing a strip or a sheet having a one or two-sided surface structure which is prepared for an adhesive connection,
wherein a hot- and/or cold-rolled strip or sheet is subjected to electrochemical graining after the rolling, wherein homogenously distributed depressions are at least in certain areas introduced into the strip or sheet by the electrochemical graining and the strip or sheet at least partly consists of an aluminium alloy of the type AA7xxx, type AA6xxx, type AA5xxx or of the type AA3xxx, in particular AA7020, AA7021, AA7108, AA6111, AA6060, AA6014, AA6016, AA6005C, AA6451, AA5454, AA5754, AA5182, AA5251 or AlMg6, AA3104, AA3103.

10 . Method according to claim 9 ,
wherein depressions with a reduced valley depth S vk of 1.0 μm to 6.0 μm, preferably 1.5 μm to 4.0 μm or 2.2 μm to 4.0 μm are at least in certain areas introduced into the strip or sheet surface by the electrochemical graining.

11 . Method according to claim 9 ,
wherein strip or sheet is subjected to a cleaning step before the electrochemical graining, in which the surface is cleaned by alkaline or acid pickling and a homogenous removal of material is carried out.

12 . Method according to claim 9 ,
wherein the electrochemical graining is carried out using HNO 3 in a concentration of 2.5 to 20 g/l with a charge carrier input of at least 200 C/dm 2 , preferably at least 500 C/dm 2 .

13 . Method according to claim 9 ,
wherein after the electrochemical graining, a passivation of the surface is carried out, preferably by applying a conversion layer.

14 . Method according to claim 9 ,
wherein a strip is electrochemically grained after soft annealing (state “O”) or after solution annealing and quenching (state “T4”).

15 . Method according to claim 13 ,
wherein the method steps are carried out in-line on a production line:
uncoiling the strip from a coiler;
cleaning and pickling the strip;
at least in certain areas electrochemically graining the strip; and
at least in certain areas applying a forming aid and/or a conversion layer or alternatively a protective oil.

16 . Adhesive connection, in particular in a motor vehicle, between at least two join partners, wherein at least one join partner is a sheet according to claim 8 and the adhesive connection is provided in at least one area of the sheet which has a surface structure produced by electrochemical graining.

17 . Strip or sheet consisting of an aluminium alloy for a use according to claim 1 , wherein
the strip or sheet consists of an aluminium alloy of the type AA7xxx, type AA6xxx, type AA5xxx or of the type AA3xxx, the strip or sheet at least in certain areas has a surface structure prepared for an adhesive connection, wherein the surface structure has depressions which were produced using an electrochemical graining process, the surface structure which is at least provided in certain areas is provided on at least one or on both sides of the strip and has a reduced valley depth S vk of 1.0 μm to 6.0 μm or 1.5 μm to 4.0 μm, particularly preferably 2.2 μm to 4.0 μm.

Assignees

• Kernig Bernhard
• Brinkman Henk Jan
• Eckhard Kathrin
• Nitzsche Gernot
• Hirschmann Frank
• Hydro Aluminium Rolled Prod

Inventors

• Kernig Bernhard
• Brinkman Henk-Jan
• Eckhard Kathrin
• Nitzsche Gernot
• Hirschmann Frank

Classifications

• C22C21/02

  with silicon as the next major constituent · CPC title

• C22C21/10

  with zinc as the next major constituent · CPC title

• C25F1/00

  Electrolytic cleaning, degreasing, pickling or descaling · CPC title

• B32B15/20

  comprising aluminium or copper {(B32B15/016 and B32B15/017 take precedence)} · CPC title

• C22C21/00

  Alloys based on aluminium · CPC title