WO2021001778A1

WO2021001778A1 - Method for connecting one component to another component

Info

Publication number: WO2021001778A1
Application number: PCT/IB2020/056249
Authority: WO
Inventors: Stefan MARSCH; Andreas Hennings
Original assignee: Nemak, S.A.B. De C.V.
Priority date: 2019-07-02
Filing date: 2020-07-02
Publication date: 2021-01-07
Also published as: DE102019117851A1

Abstract

The invention relates to a method for connecting a first component (1) which is made of a lightweight metal alloy and has a joint surface (2, 3, 4) to another component which likewise has a joint surface, wherein a) material is removed from at least the joint surface (2, 3, 4) of the first component (1), b) the joint surface of the other component is positioned on the joint surface (2, 3, 4) of the first component (1) such that the joint surfaces (2, 3, 4) of the first component (1) and the other component lie against each other, and c) a force-fitting, form-fitting, and/or bonded connection is produced between the first component (1) and the other component in the region of the joint surfaces (2, 3, 4) lying against each other in order to meet even the highest requirements regarding the surface quality of the joint surface of the component provided for the connection process with minimum effort. The invention proposes carrying out the process of removing material from the joint surface (2, 3, 4) of the first component (1) in step a) using high-pressure water jets.

Description

Method for connecting a component to another component

The invention relates to a method for connecting a first component, which is cast from a light metal casting alloy and has a joining surface, with a further component, which also has a joining surface.

In order to create defined conditions on the joining surface of the first component before connecting it to the other component, in operational practice in a first work step on the relevant surface of the first component, material is usually removed over a certain thickness of the surface layer adjacent to the relevant joining surface. This work step, also known as "activation", gives the joining surface a certain surface roughness and, for example, there are.

Existing oxide layers or the like removed, which could have an adverse effect on the durability of an adhesive connection. However, there is also the case that the first component and the other component are to be connected to one another by a positive or non-positive connection, such as

for example by a rivet connection or by a

Enforcement connection, the requirement for a defined

Surface condition in the area of the surfaces where the castings and components to be connected are joined together.

The first component activated on its joining surface is in contact with the

The joining surface of the further component to be connected to it is brought so that the joining surfaces of the first component and the further component lie against one another.

Then in the area of the mutually adjacent joining surfaces of first component and from the further component a force, shape and / or

material connection between the component and the further component produced.

In order to meet the requirement for a defined surface condition in the area of the joining surface that is optimized for the respective type of connection, in practice the material layer is mechanically removed from the joining surface by grinding or polishing, which could possibly negatively affect the durability of the connection to be made in the area of the joining surface .

At the same time, the grinding or polishing process creates the specified roughness on the joining surface.

In the case of flat or evenly curved joining surfaces, the mechanical material removal can be exactly reproducible by machine in an automated

Machining process to be done. However, if there are complex shapes in the area of the joining surface, such as narrow radii or

Undercuts, in many cases the required material removal can only be done by hand. This not only brings a significant amount

Processing effort, but also with regard to the

Quality assurance and the reproducibility of the processing result require special precautions, which mean additional effort.

Against this background, the task has arisen to develop a method for

To name the connection of a component with another component, with which it is possible with minimal effort, also the strictest requirements on the quality of the surface quality of the joining surface for the connection

provided component to meet.

The invention has this object by what is specified in claim 1

Procedure solved. It goes without saying that when performing the

method according to the invention, the skilled person not only

The process steps mentioned in the claims and explained here have been completed, but also old other steps and activities that are regularly carried out in the practical implementation of such processes in the prior art, if the need arises.

Advantageous refinements of the invention are given in the dependent

Claims specified and, like the general inventive concept, are explained in detail below.

In a method according to the invention for connecting a first component, which is made of a light metal alloy and has a joining surface, with a further component, which also has a joining surface, is thus in accordance with the prior art explained at the beginning a) at least on the joining surface of first component a material removal

made, b) the further component with its joining surface on the joining surface of the first

The component is attached so that the joining surfaces of the first component and the further component lie against one another, and c) a non-positive, positive and / or material connection is established between the first component and the further component in the area of the mutually adjacent joining surfaces.

According to the invention, in step a) the material is removed from the

Joining surface of the component made by means of high pressure water jets. The invention thus makes use of the possibility already known from the prior art for roughening the surfaces of cylinders of internal combustion engines (see EP 0 568 315 B1 and DE 10 2009 019 674 B4), targeted material removal by means of high-pressure water jets to be carried out on the respective processed surface and to set a certain surface roughness. It has been shown that high-pressure water blasting is not only suitable for producing a surface condition on a light metal component that makes the correspondingly processed surface suitable for a surface coating or the like, but also for removing a surface layer that is so thick that optimal conditions are met are created for making a

material connection (gluing) or non-positive and / or positive connection (riveting, clinching connection, screwing, etc.).

It proves to be particularly favorable that by means of

High pressure water jets even with an automated one

Execution of the process, complex surface designs and processes of the joining surfaces can be processed without problems So by means of a

High-pressure water jet hiriter cuts, narrow radii and the like can be easily processed.

In order to ensure sufficient material removal, the

Water jet, which according to the invention in high pressure water jets in

Work step a) is directed at the joining surface to be processed, can be applied with a pressure of 600-850 bar, with particularly good

Working results are to be expected at a pressure of 650 - 750 bar.

The effect of the high-pressure water jet can be further optimized in that the high-pressure water jet is emitted in a pulsed manner, with pulsing in the ultrasonic range having proven to be particularly effective. Typically, according to the invention, the pulses have a frequency from 18,500 - 22,000 Hz, whereby pulses from 19,500 - 20,000 Hz have proven to be particularly effective.

The feed rate with which the high pressure water jet is moved along the surface to be processed is typically 1 to 50 mm / s.

The design of the opening of the nozzle used for discharging the

High pressure water jet is used, especially the appropriate one

Nozzle diameters are empirically determined within the framework of the parameters explained above (pressure, optional pulsation, feed rate) so that the desired material removal is carried out within a specified time unit.

A certain evenness of the surface to be treated can apply as a target value for the material removal. With the method according to the invention, surface flatnesses can thus be produced without any problems, in which the maximum deviation from a perfectly flat surface is at most ± 0.5 mm, in particular at most ± 0.3 mm or at most 0.2 mm.

According to the invention, the high-pressure water jet can also be applied as a function of the topography of the surface to be processed. For this purpose, the surface topography can be captured by image technology (e.g. by a surface scan). From the recorded topography, the areas can then be determined where a material removal for the production of a

certain flatness of the total surface is required. In this way, the high-pressure water jet machining according to the invention can be limited specifically to those surface areas in which for each

Desired evenness of the entire surface requires more intensive material removal. Less uneven surface sections can then be left out less intensively or during processing because they already meet the requirements placed on the flatness of the overall surface. The procedure according to the invention by using the

The mean surface roughness Rz (determined in accordance with DIN EN 25178) that can be achieved on the surface of the processed joining surface of the first component by high pressure water blasting is typically 1pm-6pm after step a).

It can be done in step a) by high pressure water jets

especially when the water jet is applied at the pressures specified above, a 0.1-0.15 mm thick surface layer can be reliably and evenly removed from the joining surface of the first component, evenly and completely reproducibly. With the method according to the invention, it is thus possible, reliably and reproducibly, to remove the natural oxide layer that is inevitably forming on the joining surface before the joining process. The

The joining surface treated according to the invention has a defined, uniform surface which ensures an improved joining result.

It goes without saying that in the event that both components to be joined are made of a light metal material, the high-pressure water jet treatment according to the invention can be carried out on the joining surfaces of both the first and the further component to be joined with it.

A particular advantage of the application according to the invention

High-pressure water jets for processing the joining surface of the respective component means that the machining of the joining surface can be integrated into a process in which the respective component is cleaned for further processing. As for the cleaning of the respective component and the high-pressure water jets used according to the invention

If the same medium can be used on the joining surface of the component in question, the joining surface can be cleaned and processed according to the invention

can be carried out consecutively or simultaneously in a continuous process without any problems. According to the invention, the washing process carried out to clean the respective component, before, during or after the work step a) completed by using high pressure water blasting.

The method according to the invention is particularly suitable for preparing a component which is glued to the further component in step c) in the area of their mutually adjacent joining surfaces.

The method according to the invention can be used for components that are

Cast parts made from a light metal casting alloy, in particular one

Cast aluminum alloys are cast particularly effectively.

Examples of components that can be connected to one another in a particularly simple and effective manner in accordance with the invention are, on the one hand, a carrier or a housing, which form the first component, and, on the other hand, a battery, which is used to store and dispense electrical energy is provided and forms the second component to be connected to the first component. The invention makes it possible here in a simple manner the joining surface of the carrier or the housing on which the battery with its associated

The joint surface comes into contact with one another in such a way that there is such an intensive thermally conductive contact between the joint surfaces of the housing or carrier on the one hand and the battery on the other hand after step c) that there is no need for additional aids for heat transfer, such as thermal paste and the like can be.

The invention is explained in more detail below with reference to a drawing showing an exemplary embodiment.

The single figure shows schematically a section of a structural component 1 of a support structure, not shown here, for a structure not shown here either

illustrated motor vehicle body. The structural component 1 can be, for example, a cross member of the rear wheel suspension or the like, which is intended to be connected to the adjacent components, for example made of sheet metal, during the assembly of the supporting structure by means of adhesive bonds, which are also not shown here. The components with which the structural component 1 is to be connected can be a floor panel, a side member or the like.

The structural component 1 has been cast in a conventional manner from a cast aluminum alloy known for this purpose.

For the connection to the respective component of the supporting structure of the

Motor vehicle body are provided on the structural component 1 at different points, joining surfaces 2,3,4. The joining surfaces 2, 3, 4 can be curved in narrow radii, arranged in areas of the structural component 1 where free direct access through other shaped elements of the

Structural component 1 is hindered, or be provided with undercuts, which are required, for example, in addition to the material connection produced by the intended gluing, also a

Establish positive coupling of the structural component 1 with the component to be connected.

In order to prepare the joining surfaces 2, 3, 4 for gluing, the structural component 1 goes through a conventional washing process in which the

Surfaces of the structural component 1 completely from fat and others

Residues are freed that originate from the previous work steps that the structural component 1 has gone through during its production.

A material-removing processing is integrated into the washing process, by means of which a cover layer which is present on the joining surfaces 2, 3, 4 and adjoining the free surface of the joining surfaces 2, 3, 4 over a thickness of for example 0.1 mm away and on the joining surface a

Surface roughness Rz of, for example, 200 μm (0.2 mm) is produced in order to activate the joining surfaces 2, 3, 4 for the subsequent gluing with the respectively assigned component of the supporting structure.

A conventional one is used for this material-removing machining

High-pressure water jet device provided, from the ^' here only the

Nozzle head 5 is shown. The nozzle head 5 can be held, for example, on a robot arm or a comparable adjusting device which can move the nozzle head 5 in all degrees of freedom C, U, Z, which

are required to connect the joint surface 2, 3, 4 to be machined with that of the nozzle head 5 in a systematic sequence of movements

applied high-pressure water jet 6 successively over a processing path P provided for this purpose and running over the respective joining surface 2, 3, 4 at a feed rate of 1-50 mm / s.

The high-pressure water jet 6 exiting from the nozzle head 5, which is typically subjected to a pressure of up to 850 bar, hits the respective joining surface 2, 3, 4 with high kinetic energy, so that in the respective impact area the cover layer of the cast substrate of the structural component that supports it 1 completely detached in the form of fine particles and, at the same time, a surface structure characterized by irregularly distributed mountains and valleys are left behind on the exposed surface, which is what is required

Form surface roughness Rz,

The material particles removed from the joining surfaces 2, 3, 4 are washed away by the high-pressure water jet 6, so that completely clean joining surfaces 2, 3, 4 are available after processing by the high-pressure water jet. To produce the adhesive connection, the joining surfaces 2, 3, 4 machined in this way are wetted in a known manner with an adhesive. Subsequently, the structural component 1 with its joining surfaces 2, 3, 4 is attached to the corresponding joining surfaces of the assigned components of the supporting structure, so that the now between the joining surfaces 2, 3, 4 of the structural component 1 and the joining surfaces of the component to be connected sitting on them the support structure seated adhesive become effective and after the possibly required curing a material bond is established.

REFERENCE MARK

1 structural component, cast from a cast aluminum alloy

2,3,4 joining surfaces of the structural component 1

5 nozzle head

6 high pressure water jet

P path followed by the high pressure water jet 6 the respective

Joining surface 2, 3, 4 covered

C, U, Z spatial directions (degrees of freedom of movement of the nozzle head

5)

Claims

PATENT CLAIMS

1. A method for connecting a first component (1) consisting of a

Light metal alloy is made and has a joining surface (2,3,4), with a further component, which also has a joining surface, wherein a) at least on the joining surface (2,3,4) of the first component (1)

Material is removed, b) the further component with its joining surface is attached to the joining surface (2,3,4) of the first component (1) so that the joining surfaces (2,3,4) of the first component (1) and the rest Component lie against one another, and c) in the region of the mutually adjacent joining surfaces (2,3,4) a force-fit, form-fit and / or material connection is established between the first component (1) and the further component, characterized in that in Step a) the material is removed from the joining surface (2,3,4) of the first component (1) by means of high pressure water jets.

2. The method according to claim 1, characterized in that the water jet directed at high pressure water jets in step a) onto the joining surface (2,3,4) of the first component (1) is applied at a pressure of 600-850 bar.

3. The method according to any one of the preceding claims, characterized in that the water jet directed at high pressure water jets in step a) on the FDgefläche (2,3,4) of the first component (1) is pulsed at a frequency of 18,500-22,000 Hz.

4. The method according to any one of the preceding claims, characterized

characterized in that the mean surface roughness Rz of the joining surface (2,3,4) of the first component (1) after work step a) is 1pm - 6pm.

5. The method according to any one of the preceding claims, characterized

marked that in step a) by the

High-pressure water jets from the joining surface (2, 3, 4) of the component (1) remove a 0.1-0.15 mm thick cover layer adjacent to the surface of the joining surface.

6. The method according to any one of the preceding claims, characterized

characterized in that the joining surface (2,3,4) of the component (1) is washed before, during or after work step a).

7. The method according to any one of the preceding claims, characterized

characterized in that the first component (1) and the further component in step c) are glued to one another in the area of their mutually adjacent joining surfaces (2,3,4).

8. The method according to any one of the preceding claims, characterized in that the first component (1) and the further component in step c) are welded to one another in the region of their mutually adjacent joining surfaces (2,3,4).

9. The method according to any one of the preceding claims, characterized

characterized in that the first component (1) consists of a

Light metal casting alloy is cast.

10. The method according to claim 9, d a d u r c h characterized in that the light metal casting alloy is a cast aluminum alloy.

11. The method according to claim 1Ö, characterized in that the first component is a carrier or a housing and the second component is a battery which is provided for storing electrical energy.