DE102004029230A1 - Metallic join partners` connecting method for manufacturing vehicle body, involves grouting two join partners, so that material of latter partner penetrates into recess of former partner to produce fixed connection between partners - Google Patents

Abstract

The method involves molding all-sides of join partner (1), and aligning join partners (1, 2), such that they overlap each other in a connection zone at a lap joint. The join partner (1) with recess is grouted with the join partner (2) having recess, such that the material of the partner (2) penetrates into the recess of the partner (1) to produce a fixed connection between the join partners by an adhesive bond and/or form fit. An independent claim is also included for a component produced by connecting two join partners in an area of a lap joint formed between the join partners.

Description

The The invention relates to a method for joining two joining partners by lap joint and a Component produced from a first and a second joint partner by joining in the area of a lap joint formed between the two joining partners.

By Minimizing the weight of vehicles can be significant Savings on the drive required for the respective vehicle Achieve energy. Therefore, there is especially in the field of body shop for a long time already the demand for materials that effectively reduce allow the weight. These materials should on the one hand the required stabilities and on the other hand a for the production of the respective component sufficient deformability exhibit.

With the introduction of components made of different, to the respective strength and Deformability requirements adapted materials produced are weight-saving mixed construction solutions available, the especially in the area of load-bearing, heavily loaded in operation Parts of automobile bodies have been used successfully.

Such "tailored blanks" become, for example by welding of at least two steel sheets of different thickness, strength and Deformability formed with each other. That way you can produce a semi-finished product that is particularly loaded in the area of operation Zone of a formed from the Tailored Blank component a special Strength identifies while it can be deformed particularly well in another, less heavily loaded zone is.

Next The load-bearing body of a vehicle also provides the vehicle interior options the weight reduction. This applies, for example, to such areas the interior, while providing adequate dimensional stability and formability have to own but exposed to less high dynamic loads during operation are. This is, for example, the parcel shelf in Car sedans.

Basically suitable for the production of such components sheets made of light metal materials or plastics are made. The advantage of less weight stands however in components made of light metal materials the disadvantage of reduced strength and therefore reduced due dimensional stability across from.

By the combination of solid steel materials with lightweight alloy materials can be both solid and dimensionally stable as well as lightweight components to disposal put. In contrast to the known "tailored-blank" solutions However, these combinations of materials usually do not work together weld. Therefore, in metalworking metal moldings and sheets are increasingly used where a made of solid steel metal part by a suitable joining operation connected to a part made of light metal material becomes. So are the construction of bodies for motor vehicles and rail vehicles or aerospace steel / aluminum, steel / copper, Steel / brass or magnesium / aluminum combinations used.

Next The combination of metals also offers the possibility of Combine plastics with metals. Also in this case comes one welding the joining partner not in question.

A method of producing a metal product by joining a flat product consisting of a steel and a light metal material is known from DE 196 40 612 C1 known. According to the known method, the joining takes place in a roll gap into which the parts to be joined together are inserted at an acute angle such that their mutually associated edge regions overlap in a lap joint. Before the two parts are then pressed together with one another in the nip at a surface pressure limited to the area of the overlap, at least one of the flat products is heated by radiation energy to a temperature below the melting temperature of its material immediately before its contact with the other flat product. As a result of this heating, the pressing forces required for joining are markedly reduced compared with the forces required for cold pressing.

In order to compensate for a material flow from the area of the lap joint despite the heating during the pressing of the metal parts, it is provided according to the known method to profile the surface of one of the parts involved in the surface pressure. The surface profiling preferably consists of grooves extending along the lap joint. Their advantage is seen in the fact that they allow sufficient surface pressure in the region of the lap joint with sufficient change of material flow. In this way, the material which begins to flow as a result of the surface pressures occurring during the rolling of one joining partner on the other, in the formed between the elevations of the grooves receiving spaces flow.

With the in the DE 196 40 612 C1 Although described measure can prevent thinning of the interconnected sheets in the region of the overlap shock. Practical experience shows, however, that the connections made in this way still do not withstand the stresses prevailing in the operation. This applies in particular to the occurrence of shearing forces acting transversely or perpendicular to the lap joint.

The The object of the invention was therefore to provide a method with a permanently fixed joint between two, in particular metallic, joining partners can be produced. Likewise, a component was to be created, the joining of two firmly interconnected joint partners is made.

• – Einformen von allseitig durch eine Umrandung umgrenzten Ausnehmungen in das Material des einen Fügepartners im Bereich einer Fügezone,
• – Ausrichten der Fügepartner derart, dass sie einander mindestens in der Fügezone im Überlappstoß überlappen;
• – Verpressen des mit den Ausnehmungen versehenen Fügepartners mit dem anderen Fügepartner mindestens im Bereich der Fügezone derart, dass der Werkstoff des anderen Fügepartners in die Ausnehmungen des mit den Ausnehmungen versehenen Fügepartners dringt und eine durch Formschluss und / oder einen durch das Verpressen bewirkten Stoffschluss feste Verbindung zwischen den Fügepartnern hergestellt ist.

With regard to the method for joining two joining partners in a lap joint, this object is achieved in that such a method according to the invention comprises the following steps:

• Molding in recesses which are bounded on all sides by a border into the material of the one joining partner in the region of a joining zone,
• - Align the joining partners such that they overlap each other at least in the joint zone in the lap joint;
• - Compressing of the joining partner provided with the recesses with the other joining partner at least in the region of the joining zone such that the material of the other joining partner penetrates into the recesses of the joining partner provided with the recesses and a fixed connection by positive locking and / or a material connection caused by the pressing is made between the joining partners.

According to the invention become two joining partners in a joining operation in the area of a lap joint positively, cohesively or by a combination of form and material connection connected. For this purpose, at least in one of the joining partners Recesses molded. In these recesses of the one joining partner is in the course of the process according to the invention Material of the other joining partner pressed.

On this way becomes an intimate interlocking interlocking of both joining partner accomplished in the area of the lap joint, which is suitable, the one joining partner in each degree of freedom with the other joint partner keep connected. Such a compound according to the invention achieved by two different joining partners proves to be sufficiently strong even under dynamic load to cope with the demands that arise in practical use of metal products of the type in question.

alternative or in addition to the positive Connection between the joining partners can according to the invention about that In addition, an entering due to the compression material connection be used to the joining partners firmly connect with each other. This adhesion occurs during compression the joining partner as a result of the joining zone limited high surface pressures in the form of a cold welding one. When pressing the two materials, there is a relative movement the one to be joined Parts, whereby the adhering to the surface Oxide layer is torn open. Through the direct contact at the same time high pressure creates a positive and / or fluid connection, which has no dirt effect, so that a permanently safe Connection is made.

The Invention allows it is simple, with little technical effort in series production feasible Way, joining partners permanently connect with each other on a conventional basis Ways, for example by welding, not be connected can. This is how the special advantages of different materials can be achieved exploit and at the same time guarantee high quality of use.

Accordingly The above object is related to a component made of a first and a second joint partner by joining produced in the region of a lap joint formed between the two joining partners is solved by that the joining partners by effective in all degrees of freedom positive locking and / or in Consequence of press forces adjoining material connection are firmly connected, by the material of the one joining partner has penetrated into recesses, which in the other joining partner are formed.

Especially for the large-scale Application, the inventive method is then when the joining partner Flat products, such as ribbons, Sheets and sheet metal blanks, or molded parts produced from flat products are. With such flat products can be in accordance with the invention metal products produce, in the nature of "tailored blanks" different properties of different Materials in for optimally combined with each other are.

Thus, with the invention, a very wide variety of materials can be coupled to one another in this way, that they are securely connected even under continuous load. Therefore, the inventive method is particularly suitable for processing joining partners, one of which has a higher strength than the other. For example, the invention is particularly suitable for joining joining partners, one of which is made of a steel and the other of a light metal material, such as aluminum, copper or brass. Likewise, the invention allows permanent solid metal / plastic compounds, such as steel / plastic or light metal / plastic compounds to produce. It is also possible to connect in accordance with the invention magnesium parts made of other light metal materials or plastic parts.

in the With regard to minimizing the pressing forces become the recesses expedient manner in the joint partner with the higher Strength molded.

In such cases, in which flat products or moldings produced therefrom in accordance with the invention together should be able to do the joining operation be particularly easily performed by the fact that the joining zone respectively extends along an edge region of the flat products. Depending on the shaping of the component produced in this way the joining zone along the longitudinal edge flat products that are locally can vary.

According to the invention serve recesses of the one joining partner as recordings for the material of the other joining partner, whose material is pressed into these receptions. In accordance with the invention in the a joining partner introduced recesses may be depressions, such as blind holes, or openings through the joining partner, like slots, perforations, etc., act. It is essential that the respective recesses are each formed such that in Consequence of the penetration of the material of the other joining partner into the recesses of the first joining partner intensive joining of both joining partners in the area of the joining zone occurs. The local Distribution of the recesses, their orientation and / or their dimensions are thereby preferably chosen that they are in contact with the joint partners each locally are adapted to occurring loads.

Provided the material of the joining partner, its material in the recesses of the other joining partner is pressed, is sufficiently soft, can be pressed without previous warming the soft material with the desired inventive success carry out. However, in order to facilitate the pressing, the joint partner, the material in each case in the recesses of the recesses provided joining partner is pressed, in a conventional manner before pressing at least in the area of the joining zone of the joining partner provided with the recesses, to a joining temperature heated become. By such a warming the softened into the recesses material is softened, so that only reduced press forces are required and a low strain hardening of the softer Material enters.

The warming can be carried out before or after the work step "Aligning the joining partners". In any case, should however, the joining temperature so chosen be that the temperature of the heated joining partner at the time of Pressing is above a minimum temperature at which it is too a softening of that material comes from which the heated joining partner is made.

According to one In the first variant of the invention, the joining temperature is preferably adjusted so that it is below the melting temperature of the material, from the the heated one joining partner is made. On the one hand can so unwanted structural changes in the heated Zone of the respective joining partner be avoided. On the other hand, such a warming affects especially then Cheap off when the to be heated joining partner evenly heated in a continuous process and that too Pressing continuously at a substantially constant contact pressure carried out becomes.

Depending on available standing production facilities, the special properties of the processed materials as well the particular made to the respective connection However, requirements may also be advantageous in the field the section of the heated joint partner, each of the joining zone of the joining partner provided with the recesses, the joining temperature locally limited to one above the melting temperature of the material of the heated joining Partners increase the temperature. In such a focused on the respective joining zone heating can be particularly low pressures for pressing the joining partners be used. This proves to be particularly favorable if Materials of widely varying hardness or high pressing forces to unwanted Deformations in the vicinity of the joining zone or of the lap joint. For such Case provides the invention, the pressure exerted during pressing pressure in the area of over increased the melting temperature Sections of the heated joining Partners across from the other sections.

At the Joining of made of different soft materials existing parts, at where the material of each softer material allows heating and the softening temperature of the softer material is lower than those of the harder ones the recesses expediently in the harder Material molded while the softer material at joining temperature heated becomes. In this way, the for the warming necessary heat input be reduced to a minimum.

Basically, all heat sources can be used for heating be used, with which the required amount of heat sufficiently concentrated in the respective sections of the to be heated joining Partners bring in. So it is conceivable, for example, inductively working To use heaters. It is particularly effective the warming but by means of radiation energy, in particular by means of a laser beam, carry out. Allow radiation energy sources the precisely metered warming over one defined effective depth and extent of the material to be heated.

Around a secure connection of the parts to be joined To ensure the width of the joint zone should be at least two times the least thickness, which has one of the joining partners in the region of the joining zone.

The Invention allows the joining of joining partners of any thickness. So can Sheet thicknesses are processed, as is typical in the field of the body shop occur. However, significantly larger material thicknesses are possible.

following The invention will be illustrated with reference to an exemplary embodiments Drawing explained in more detail. It show each fragmentary and schematic:

1 a prepared for joining first metal part in plan view;

2 - 4 the first and a second metal part at different times of the joining in each case in cross section;

5 a finished metal product of the first and second metal parts in cross-section;

6 - 8th different variants of a metal product joined from a first and second metal part in each case in cross section;

9 - 11 different variants of a first prepared for joining metal part respectively in plan view.

To produce a metal product M, two are used as metal parts 1 . 2 present joining partners by joining in a lap joint 3 connected with each other. At the first metal part 1 it is a steel sheet of high strength and hardness, while the second metal part 2 a much softer aluminum sheet of light weight. The thicknesses D of the metal parts 1 . 2 correspond to the usual in the automotive industry sheet thicknesses of 0.6-3.5 mm.

In the first metal part 1 are by punching with the aid of a punch, not shown, recesses 4a - 4i molded in the form of blind hole-like depressions. The metal part 1 is fed to the punching tool in a continuous, automated process. The punching tool embosses the recesses 4a - 4i in a joining zone 5 along a longitudinally associated edge of the metal part 1 extends and the width of the width B of the lap joint 3 equivalent.

The recesses 4a - 4i are in alternating order in rows of four or five recesses 4a - 4e . 4f - 4i each sitting on the gap in the metal part 1 arranged. The respective externally positioned recesses 4a . 4e respectively. 4f . 4i each row are related to the surface 6 the top of the metal part 1 each disposed at a larger angle obliquely facing outward as the next to each adjacent arranged recesses 4b . 4d respectively. 4g . 4h , The recess arranged in the middle 4c is at the five recesses 4a - 4e having rows also perpendicular to the surface of the metal part 1 aligned ( 1 ).

Following the molding of the recesses 4a - 4i in the first of steel material existing metal part 1 becomes the second metal part made of aluminum material 2 by means of a suitable, also not shown here device aligned so that it with its one extending in its longitudinal direction edge strips the joint zone 5 of the metal part 1 covered and the lap 3 between the metal parts 1 and 2 is formed. The width B of the lap joint 3 , the number and distribution of the recesses 4a - 4i is dimensioned such that in the area of the lap joint 3 sufficient connection formed between the metal parts, in order to safely endure the loads occurring in the practical use of the metal product M in an automobile body ( 2 ).

After alignment, the metal part consisting of the soft aluminum is formed 2 by means of a laser 7 generated laser beam 8th in his on the width B of the overlap 3 be restricted, the metal part 1 associated edge strips 9 heated to a joining temperature which is 300 ° C to 630 ° C. This joining temperature is thus below the melting point of the aluminum material, but in a temperature range in which it comes to a softening of this material ( 3 ).

The flow stress of the Al material is so greatly reduced in this way that in the subsequent pressing operation pressures in the range of 12,000 kN / cm ² to 20,000 kN / cm ² sufficient to the Al material of the second metal part 2 in the recesses 4a - 4i of the first metal part 1 to press. For this purpose, a press roll 10 over the heated edge area 9 of the metal part 2 rolled, with the appropriate pressure on the edge area 9 acts. The effective range of the press roll 10 is on the edge area 9 limited, leaving only this edge area 9 is deformed by the compression. The recesses 4a - 4i of the first metal part 1 be this way with Al material of the second metal part 2 filled ( 4 ).

As a result, the metal product M is obtained, in which the two metal parts 1 and 2 through the form-fitting in the recesses 4a - 4i of the metal part 1 cross-Al material of the second metal part 2 are firmly connected. The orientation of the recesses 4a - 4i Make sure that the metal parts 1 . 2 are firmly and permanently firmly coupled with each other under the practical use of the metal product M dynamic loads in all degrees of freedom ( 5 ).

If necessary, the strength of the connection between the metal parts 1 . 2 be increased by the fact that the recesses 4a - 4i are not formed in the form of blind holes, but as through holes extending from the top to the bottom of the metal part 1 extend ( 6 ).

Another possibility, the load occurring in the respective application case load capacity in the area of the lap joint 3 made connection between the metal parts 1 and 2 to ensure the size and number of recesses 4a - 4i to vary. For example, a smaller number of recesses 4y - 4l provided that the dynamics of the load occurring during operation are lower ( 7 ).

Manufacturing technology can be easily manufactured in the metal part 1 Molded recesses then, when all in the same way perpendicular to the surface 6 of the metal part 1 are aligned. In order to support the strength of the positive connection in all degrees of freedom, the respective recesses 4m - 4o one from the bottom 11 of the metal part 1 to the surface 6 have decreasing diameter from the top. Such recesses 4m - 4o can then be easily from the bottom 11 in the metal part 1 molding ( 8th ).

The arrangement and number of recesses, as mentioned, can be adapted to the loads which occur in each case during the practical operation of the metal product M. So can the recesses 4p be arranged in a uniform arrangement in uniform rows ( 9 ). Also, gaps can be regularly or irregularly arranged recesses 4q be provided whose distribution according to the locally occurring loads may be different ( 10 ). Another possibility, a particularly secure fixed positive connection between the metal parts 1 . 2 to produce as a joining partner, is that in the metal part 1 slit-like recesses 4r be formed. Also these recesses 4r can regularly and regularly ( 11 ) or irregularly arranged.

All recesses 4a - 4r can not only be punched or comparable mechanical methods in the metal part 1 einformen, but also by means of beam energy, for example by laser cutting or laser drilling.

In addition to the explained press roller 10 can for pressing the metal parts 1 . 2 also stamps or other tools are used. Such punches are particularly suitable for pressing when only locally limited pressing forces are to be applied or the pressing forces over the longitudinal extension of the lap joint 3 have to be varied.

Under certain circumstances, it can also be beneficial in both metal parts 1 . 2 Mold in recesses, and both material of the metal part 2 in recesses of the metal part 1 as well as material of the metal part 1 in recesses of the metal part 2 to squeeze to a strongest possible connection of both parts 1 . 2 to reach.

1

out Steel material manufactured metal part

2

out Aluminum material manufactured metal part

3

lap

4a-4r

recesses

5

joint zone

6

Surface of the Top of the metal part 1

7

laser

8th

laser beam

9

heated edge area of the metal part 2

10

press roll

11

bottom of the metal part 1

B

width of lap 3 and the joining zone 5

D

thick the metal parts 1,2

M

metal product

Claims (26)

Method for connecting two joining partners ( 1 . 2 ) in a lap joint ( 3 ), which comprises the following steps: - molding in recesses bounded on all sides by a border ( 4a - 4r ) into the material of the one joining partner ( 1 ) in the region of a joining zone ( 5 ), - aligning the joining partners ( 1 . 2 ) such that they at least in the joining zone ( 5 ) in overlap ( 3 ) overlap; - pressing the with the recesses ( 4a - 4r ) provided joining partner ( 1 ) with the other joint partner ( 2 ) at least in the region of the joining zone ( 5 ) such that the material of the other joining partner ( 2 ) into the recesses ( 4a - 4r ) of the recesses ( 4a - 4r ) provided joining partner ( 1 ) and a connection between the joining partners caused by positive locking and / or a material connection caused by the pressing 1 . 2 ) is made. Method according to one of the preceding claims, characterized in that at least one of the joining partners a metal part ( 1 . 2 ). Method according to one of the preceding claims, characterized in that the joining partners ( 1 . 2 ) Flat products, such as ribbons, sheets, sheet metal blanks, or molded parts produced from flat products are. Method according to one of the preceding claims, characterized in that the material of the one joining partner ( 1 ) has a higher strength than the material of the other joining partner ( 2 ). Method according to claim 4, characterized in that the recesses ( 4a - 4r ) in the joining partner ( 1 ) are formed with the higher strength. Method according to one of claims 4 or 5, characterized in that both joining partners ( 1 . 2 ) are each made of a metal material and that the one joining partner ( 2 ) consists of a light metal material. Method according to claim 4 or 5, characterized that one joining partner is made of a metal material and the other of a Plastic exists. Method according to one of the preceding claims, characterized in that the recesses ( 4f - 4r ) are formed as openings. Method according to one of the preceding claims, characterized in that the recesses ( 4a - 4e ) are formed as blind holes. Method according to one of the preceding claims, characterized in that the local distribution of the recesses ( 4a - 4r ), their orientation and / or their dimensions to those in use of the joining partners ( 1 . 2 ) are adapted to locally occurring loads. Method according to one of the preceding claims, characterized in that the joining zone ( 5 ) in each case along an edge region of the joining partners ( 1 . 2 ). Method according to one of the preceding claims, characterized in that the joining partner ( 2 ), whose material in the recesses ( 4a - 4r ) of the recesses ( 4a - 4r ) provided joining partner ( 1 ) is pressed before pressing at least in the region of the joining zone ( 5 ) of the recesses ( 4a - 4r ) provided joining partner ( 1 ), is heated to a bonding temperature. A method according to claim 12, characterized in that the bonding temperature is above a minimum temperature at which it comes to a softening of the material from which the heated joining partner ( 2 ) is made. Method according to one of claims 12 or 13, characterized in that the bonding temperature is below the melting temperature of the material from which the heated joining partner ( 2 ) is made. Method according to one of claims 1 to 13, characterized in that in the region of the portion of the heated joining partner ( 2 ), each of the joining zone ( 5 ) of the recesses ( 4a - 4r ) provided joining partner ( 1 ), the joining temperature locally limited to one above the melting temperature of the material of the heated joining partner ( 2 ) is increased temperature. A method according to claim 15, characterized in that the pressure exerted during pressing pressure in the region of the above the melting temperature elevated portions of the heated joining partner ( 2 ) compared to the other sections of this joining partner ( 2 ) is reduced. Method according to one of the preceding claims, characterized in that the heating by means of a laser ( 7 ) is carried out. Method according to one of the preceding claims, characterized in that the width (B) of the joining zone is at least twice the smallest thickness (D), that of one of the joining partners ( 1 . 2 ) in the region of the joining zone. Component manufactured from a first and a second joint partner ( 1 . 2 ) by joining in the area between one of the two joining partners ( 1 . 2 ) trained lap joint ( 3 ), characterized in that the joining partners ( 1 . 2 ) are firmly connected to one another by means of positive locking which is effective in all degrees of freedom and / or due to pressing forces, in that the material of one joining partner ( 2 ) in recesses ( 4a - 4r ) penetrated into the other joint partner ( 1 ) are formed. Component according to claim 19, characterized in that one of the joining partners ( 2 ) has a lower strength than the other joining partner ( 1 ). Component according to one of claims 19 or 20, characterized in that the joining partners ( 1 . 2 ) are made of metal material. Component according to claim 20 and 21, characterized in that the one joining partner ( 1 ) with a higher strength of one steel material and the other joining partner ( 2 ) is made of a light metal material. Component according to claim 21, characterized that the light metal material is an aluminum, copper, magnesium or brass material. Component according to claim 20 or 21, characterized in that both joining partners ( 1 ) are made of a light metal material. Component according to claim 24, characterized that one joining partner from a magnesium and the other joining partner made of an aluminum material consist. Component according to claim 19 or 20, characterized that one joining partner from a metal material and the other joining partner made of a plastic consists.