DE102008019062A1 - A seam-sealed article, a method of manufacturing an article, and a friction stir tool and a friction stir device - Google Patents

Abstract

An article (19) of at least one fiber reinforced material having a welded seam (18) is provided, wherein a fiber (4) is disposed in the seam (18). The object (19) can be produced by inserting a rotationally driven pin-shaped projection (9) into a workpiece area or into a connecting area (12) of at least two adjoining workpieces (5, 6) while rotating, by plastifying the workpiece area or the connecting area (FIG. 12) in at least one contact area between the rotating projection (9) and the workpiece area or connecting area (12) and by introducing a fiber (4) into the plasticized area (17).

Description

The The invention relates to an article with a welded seam, a method for producing an article, in particular with a friction stir process, and a friction stir tool and a friction stir device.

In Aerospace Engineering, Railway Technology and In the automotive industry complicated and large parts are needed, the conventional be made of several interconnected component. Joining parts of fiber reinforced composites, for example by welding techniques, is associated with new challenges because the parts are made up of at least consist of two different materials, the matrix material and fibers embedded therein.

Fiber reinforced composites such as fiber-reinforced Plastics and fiber-reinforced Metals and alloys have higher strength than the matrix material alone, as well as a lighter weight than conventional ones metallic structures. Consequently, they are increasingly being and space technology, rail technology and automotive engineering used.

task The invention therefore relates to a method for producing an article capable of reliably providing fiber reinforced materials with each other to connect, as well as an object of at least two together bonded fiber reinforced To create materials. It is another object of the invention To provide tools and a device with which this Procedure performed can be.

Is solved the object by the subject matter of the independent claims. Further advantageous developments emerge from the respective dependent claims.

According to the invention is a An article of at least one fiber-reinforced material with a welded seam provided, wherein at least one fiber disposed in the seam is.

At the weld together of fiber reinforced materials according to conventional Procedure, only the matrix material is welded and melted. The fibers stay firm and unmelted. This leads to a seam that only from the weld metal consists. The seam thus has no reinforcing fibers and consequently a lower strength than the body of the connected parts on. Consequently, you can Cracks in the seam when the article is mechanically stressed form or spread, the fracture of the seam and the breakage of the Lead object can. This is the subject of the invention avoided because the seam has at least one fiber that the seam even strengthened.

In an embodiment the fiber extends almost over the entire length the seam. This has the advantage that the seam through the fiber is homogeneous reinforced so that the reliability of the Connection increased becomes.

In a further embodiment the fiber has a helical or spiral shape, in particular a helical form, on. This form has the advantage that the width as well as the length of the Seam reinforced by the fiber become. The slope and the diameter of the helix (ie the screw or spiral) can over the whole length approximately be the same, or vary.

In a further embodiment Several fibers are arranged in the seam. These fibers can be together entangled or arranged side by side. The proportion of fibers can be increased in this way in the seam to the strength continue to increase the seam. It is advantageous if the strength of the seam about the strength of not welded Corresponds to parts, so that the strength of the object spatially equal is.

The Fibers introduced into the seam may be continuous fibers, but also short or Long fibers.

Of the Subject of one of these embodiments, a component an aircraft or a motor vehicle. Especially In aircraft and motor vehicles can crack due to continuous load caused by the components. This is of course for safety reasons too avoid.

The The invention also provides a method of friction stir used can, the subject of any of the preceding embodiments manufacture.

In friction stir processing and friction stir welding (FSW), it is known to bring two workpieces to be welded together into contact and hold them in this position. In the connecting region of the workpieces, a welding pin or a pin-shaped projection of a corresponding tool is inserted under rotary motion until a shoulder arranged above the welding pin on the tool rests on the surface of the workpieces. It is generated by the relative movement between the tool and workpieces heat of friction, so that adjacent Material areas in the connection area a plasticized state einneh men. The tool, while the rotating welding pin is in contact with the connecting portion, is advanced along the joining line of the workpieces so that the material around the welding pin is plasticized and then consolidated. Before the material hardens completely, the welding pin is removed from the connection area or the workpieces.

parts made of fiber-reinforced Materials, such as metal composite materials (so-called MCCs) or suitable plastic materials may in this way be butt joint, lap joint, or tee joint welded together become. The technique of friction-stirring but also applies to the repair, processing and finishing of workpieces application. Point connections can also be generated, with a forward movement of the rotating with the welding area in contact with the connection area or a translational relative movement between the rotating welding pin and workpieces not happened.

According to the invention the procedure follows the steps below. A rotary driven pin-shaped projection gets into a workpiece area or in a connecting region of at least two adjacent ones workpieces introduced with a rotating movement. The workpiece area or the connection area becomes in at least one contact area between the rotating projection and the workpiece area or connecting area plasticized and a fiber is in the plasticized area introduced.

The introduced Fiber can be an endless fiber, preferably continuous is supplied. It can but also short or long fibers are introduced. To the feeding of To simplify short or long fibers, these can be in a filler material embedded (fiber-reinforced filler material), which is introduced into the plasticized area.

Of the plasticized area is liquid, leaving a fiber in this liquid Be introduced can. This plasticized area has circulating currents, which are caused by the rotation of the projection. An endless, Solid fiber is captured by this circulating weld metal and due to flow or flow-dependent in weld positioned. Consequently, after the re-solidification of the plasticized Area the endless fiber with a flow-shaped form in the Seam between the workpieces frozen.

On Reason of these circulating currents the endless fiber becomes helical, d. H. spiral or helical, arranged in the seam, wherein the projection along the connecting line is guided linearly. By a combination of the linear movement as well as the circulating streams in the weld metal the pitch of the helix can be adjusted.

Of the Rotating driven pin-shaped The protrusion is typically part of a friction stir tool that rotates one drivable tool body includes. At the end of the tool body facing away from the drive a shoulder is provided, from which in the direction away from the drive End of the tool body the rotatable, pin-shaped Protrusion that has a smaller diameter than the shoulder having. The shoulder and the pin-shaped projection are independent of each other rotatably drivable.

The Shoulder may have at least one passage opening extending extends in the direction away from the drive end of the tool body. A fiber may be disposed in the through hole and during the Friction stir process the plasticized area of the workpiece or the connection area supplied become.

According to one embodiment the method according to the invention gets the shoulder on the workpiece area or connection area under at least temporary pressurization applied, while, while the projection is in contact with the workpiece area or connecting area, the speed of the shoulder has n = 0.

This Method is advantageous when welding thick workpieces, especially plates with a thickness greater than 6 mm. It is important again that during the rotationally driven pin-shaped Projection in contact with the material or connection area stands, the shoulder does not make any rotational movement, so through the shoulder no additional frictional heat generated at the workpiece surface becomes. This is the heat input by frictional heat generation on the surface the workpieces significantly reduced, whereby a so-called low-heat joining is possible. The additional warming deleted on the workpiece surface, so that the heat load is low here is and at the same time a homogeneous heat load over the ensures the entire penetration depth of the welding pin is. At the same time, the workpiece alloys soften less because of the heat affected zone less educated. Another positive effect is that Residual stresses are reduced so that the risk of delay is lower and an occurring delay is easier to handle.

The pointing in the direction of the pin-shaped projection surface of the workpieces is at the time by the action of the shoulder with the required pressure which is advantageously reduced by a factor of 2 to 3 compared to conventional friction stir process and is typically between 1 and 200 kN. Thus, you can work with reduced process force, which in turn has a simplified system technology result. In addition, the process-related change in the residual stress states of welded, repaired, machined or converted workpieces is reduced.

That no additional friction caused by the non-rotating shoulder causes also causes the process with a higher speed or Rotation speed of the welding pin are performed can. The speed can be compared to conventional friction stir increased by a factor of 3 to 4 are typically between 200 and 5000 revolutions per minute.

In a further embodiment gets the shoulder on the workpiece area or connection area under at least temporary pressurization applied, while, while the projection in contact with the workpiece area or connecting area stands, the speed of the shoulder is smaller than the speed of the projection is. This embodiment allows to adjust the shape of an endless fiber in the seam as the shape not only from the flow the plasticized area, but also by the speed of the Shoulder is determined.

According to one another embodiment becomes the projection in the workpiece area or connecting region moved linearly, the fiber being continuous is introduced into the plasticized area. This embodiment is used to make a long or endless fiber in a long seam introduce.

To the Connecting two adjacent workpieces, the projection relative to the adjacent workpieces along the connecting line moved the adjacent workpieces become. Alternatively, the abutting workpieces become relative moved to the projection along the line connecting the adjacent workpieces.

The Invention also provides a friction stir tool on, which comprises a rotationally drivable tool body, at its end remote from the drive a shoulder is provided, from which in the direction away from the drive End of the tool body a rotatable, pin-shaped Protrusion that has a smaller diameter than the shoulder wherein the shoulder and the pin-shaped projection are independent of one another are driven in rotation. According to the invention, the shoulder at least a passage opening on, which extends in the direction away from the drive end of the tool body.

A Fiber can be placed in the through hole be and while the friction stir process in the plasticized area of the workpiece or the connection area introduced become. This arrangement has the advantage that the passage opening and the position of the insertion the fiber as close as possible lie on the plasticized area. This allows reliable insertion of the Fiber in the seam.

In a further embodiment expands the passage opening towards the drive-facing surface of the shoulder. The fiber can through this passage opening directly above the workpiece be introduced into the plasticized area.

The Through opening can be substantially perpendicular to a direction away in the direction of drive surface the shoulder extend. This has the advantage that the guide length of Fiber, which is arranged in the shoulder, is small.

In a further embodiment the passage opening extends from a drive-facing surface of the shoulder to a in the direction of projection facing away from the surface of the shoulder. This arrangement has the advantage that the fiber source is arranged next to the tool body is. This can simplify the structure of the arrangement.

In a further embodiment the shoulder is designed such that upon rotation of the pin-shaped projection has a speed n = 0. The central idea is in it, a friction stir tool in such a way that welding pin and shoulder are decoupled from each other, so that upon rotation of the welding pin the shoulder just does not perform any rotational movement, but with respect to the to be joined or machined workpieces in the sense of rotation stands still. However, this excludes a displacement the shoulder in the axial direction of the tool is not enough. The shoulder defines an area of the friction stir tool with a larger diameter as the welding pin and ensures that at a certain penetration depth of the welding pin the shoulder on the Workpiece surface force and positive fit rests to apply the required pressure force on the workpiece surface and to prevent escape of plasticized material.

According to a preferred embodiment, the shoulder is by means of a suitable storage freed from the tool body or from a pin-shaped projection driving spindle rotation and thus contributes deliberately no additional frictional heat to the welding process, but is able to transmit the necessary vertical force on the workpieces to be joined. The shoulder is preferably mounted on the tool body by means of rolling bearings. Such bearings are for example ball, barrel, needle roller bearings or the like. Alternatively, hydrostatic or hydrodynamic plain bearings can be used to support the shoulder, to name but a few more examples.

advantageously, the shoulder is formed as a molding, which is in the direction of pin-shaped Projecting side of the bearing is arranged. The molded part, for example, a sheet metal Element (eg a steel sheet with a thickness of typically 2 to 5 mm) or cast components, can do so with a hole to perform of the pen-shaped Projection be provided, and from below (that is, from the direction of the pin-shaped Projection) are pushed onto the bearing. It is on it to pay attention that the area between molding and pin-shaped projection preferably is tightly formed to allow escape of plasticized material in the axial direction of the friction stir tool to prevent.

alternative For example, an assembly with a molded part without storage can be used.

Further It is advantageous that the edge region of the molded part is angled in such a way is that it at least partially surrounds the camp. Especially advantageous it is when the molding both the side portions of the bearing as also in the direction of the tool drive facing surface of Bearing at least partially encloses. This will ensure that when removing the tool or the pin-shaped projection from the workpiece or connecting region, the shoulder is not in the axial direction of the Tool slips or is moved. At the same time it will an adhesion of the shoulder to the surface of the welded or machined workpieces counteracted.

Conveniently, is the molding at least on its pointing in the direction of the side provided with a friction-reducing material. For this purpose, for example the material "CC Aluspeed <(RTM)>" from Cemecon as a coating be applied. As a result, the friction between the molding and Workpiece surface additionally reduced, which corresponds to the function of a sliding shoe.

According to one alternative embodiment the shoulder through the side facing a projection corresponding to the tool body arranged bearing (eg sliding or rolling bearings) formed. This poses a particularly simple embodiment, as an additional Element (eg on the molding) can be dispensed with.

Also in this alternative embodiment it is appropriate, the towards the side facing the bearing with a friction-reducing To coat the material of the aforementioned type, in turn, the Reduce friction between shoulder and workpiece surface.

Conveniently, is the pen-shaped Projection in one piece with the tool body formed, resulting in a very simple structure and the Plant technology for driving the tool or the pin-shaped projection is extremely simple, because essentially only one to be driven Spindle is required. The friction stir tool is usually formed rotationally symmetrical.

By the friction stir tool according to the invention Ensures that the workpiece material close to the shoulder not overheated becomes. This is how welding works of workpieces ensures that the otherwise prone to cold welding root area the welded joint thanks to the higher selectable compared to known friction stir welding tools Welding pin speed safe and with high quality welded becomes. It will give a uniform temperature distribution over the entire Cross section of the workpieces scored, which is a prerequisite for a high quality welded joint is.

Furthermore can the tool according to the invention in a similar way also for repair, processing and finishing of workpieces be used.

The The invention also provides a friction stir device comprising a friction stir tool one of the preceding embodiments. The projection is in a workpiece area or a connection area of at least two workpieces to be joined while rotating insertable so that during its rotation in contact with the workpiece area or connecting portion of the projection this at least in the contact area plasticized and plastified material is produced. The device further comprises a fiber source, wherein fibers via the passage opening in introduced the plasticized substance can be. The fibers can be supplied for example in the form of endless, short, or long fibers.

The device may further drive means have, with which the device can be performed linearly under rotary drive of the projection. Alternatively, the workpieces are moved linearly relative to the device, in particular the projection.

In an embodiment can shoulder on the workpieces outside the contact area between the projection and the workpiece area or connecting area are applied. The shoulder can thus perpendicular to the workpieces be driven, and thus cause a pressurization of the workpiece.

The friction stir and the device according to one of the preceding embodiments can be used for welding fiber reinforced plastics, fiber reinforced Metals or fiber reinforced Alloys or for welding of two adjoining workpieces made of fiber-reinforced plastic, fiber reinforced Metal or a fiber reinforced Alloy can be used.

The Invention will now be explained in more detail with reference to the drawings.

1 shows a cross section of an apparatus for friction stir of a fiber reinforced material with a friction stir tool and a fiber source,

2 a plan view of the device according to 1 , and

3 shows a perspective view of a component of two workpieces, with the device according to 1 be welded together.

1 shows a cross section of a device 1 for friction stir. The device 1 has a friction stir tool 2 , a fiber source 3 For example, a coil with an endless fiber 4 , And a drive, not shown. 1 also shows the use of the device 1 for joining workpieces, in this embodiment, two fiber-reinforced joining parts 5 . 6 , are.

The fiber-reinforced joining parts 5 . 6 have a matrix material of thermoplastic, for example polypropylene, in which endless fibers, such as carbon fibers, are arranged. The parts to be joined 5 . 6 , are in 1 arranged in butt joint connection adjacent to each other. Of course, the joining parts 5 . 6 , even overlapping or welded together in T-joint connection, which will not be described in detail below, but mutatis mutandis from the following description, so that the invention is not limited to the embodiments described below.

The friction stir tool 2 is rotationally symmetrical and includes a tool body 7 , which is typically formed in the form of a bearing shaft at the top, ie at the drive end, in order to form a tool receptacle in a 1 not shown drive device (eg., Rotary motor) to be recorded. At the drive end facing away from the tool body 7 is a shoulder 8th provided, from the direction away from the drive end of the tool body 7 a rotatable, pin-shaped projection 9 or welding pin 9 extends. The pin-shaped projection 9 has a smaller diameter than the shoulder 8th on.

At the in 1 illustrated embodiment, the pin-shaped projection 9 integral with the tool body 7 formed, which is a particularly simple arrangement, since only a drive mechanism for rotating the tool body 7 and thus the pin-shaped projection 9 is required. The axis of rotation of the friction stir welding tool 1 is in 1 represented by the dashed line.

Alternatively, the tool body 7 a mechanism (not shown) for receiving the welding pin 9 have, so that a replacement or displacement of the welding pin 9 along the axis of rotation (ie in the axial direction) is easily possible.

Regardless of whether the pin-shaped projection 9 integral with the tool body 7 or interchangeable, is the shoulder 8th preferably by means of roller bearings 10 on the tool body 7 arranged. Such bearings 10 can be, for example, ball, barrel or needle roller bearings. By the storage of the shoulder 8th with the rolling bearings ensures that the shoulder 8th and the welding pin 9 or the tool body 7 are independently drivable. In a preferred embodiment, upon rotation of the welding pin 9 or the tool body 7 the shoulder 8th no rotational movement and thus has a speed n = 0. That way, the shoulder becomes 8th from the welding pin 9 driving rotation freed or decoupled.

Instead of the storage by means of rolling bearings can Also hydrostatic or hydrodynamic bearings are used. However, the function of storage is the same. Alternative can also be waived storage.

In 1 is the shoulder 8th designed as a molded part. Such moldings may be sheet-like elements (eg steel sheets), castings or the like They are advantageously on their towards the welding pin 9 facing side are provided with a friction-reducing coating to reduce the friction between the shoulder 8th and the surface of the workpieces 5 . 6 in addition to diminish. For this purpose, for example, the material CC Aluspeed <(RTM)> Cemecon can be used. The edge region of the molded part can be in the axial direction of the friction stir tool 2 pointing angled and rest against the sides of the lower bearing shell. To cling to the shoulder 8th on the welded fiber-reinforced parts 5 . 6 or a shift of the shoulder 8th to avoid in the axial direction, the molded part, the rolling bearing 10 Also surrounded up to its direction towards the drive end facing side.

In the design of the molding is to ensure that a good seal between the shoulder 8th and welding pin 9 is ensured, so that plasticized material not in the axial direction, ie in the direction of the drive-facing end of the tool body 7 , can escape. This can be achieved, for example, by a hole arranged in the molding, which corresponds to the diameter of the welding pin 9 is adjusted. The molding can, for example, from below via the welding pin 9 on the camp 10 be deferred.

The shoulder 8th also has a passage opening 11 on, extending in the direction of the drive end facing away from the tool body 7 extends, and in this embodiment approximately perpendicular to the drive-facing surface of the shoulder 8th is arranged. The passage opening 11 is in the shoulder 8th next to the welding pin 9 arranged (see also 2 ). The endless fiber 4 is from the fiber source 3 through the passage opening 11 fed, leaving the end of the fiber 4 below the drive end remote from the tool body 7 is arranged.

For welding the adjoining fiber-reinforced joining parts 5 . 6 becomes the pin-shaped projection 9 as you know, under rotating motion in the connection area 12 the parts to be joined 5 . 6 introduced and along the connecting line 13 the parts to be joined 5 . 6 moved forward. This forward movement is with the arrow 14 in the 2 shown. The rotation of the projection 9 is with the arrow 15 in the 1 and 2 shown.

The rotating movement of the welding pin 9 on the surface of the fiber-reinforced parts 5 . 6 generates frictional heat due to the relative movement between tool and workpieces. This frictional heat leads to plasticization of the adjacent plates in the contact area, so that the rotating welding pin 9 can be introduced into the connection area. The plasticized substance 17 arises at the connecting line and flows circulating around the welding pin 9 around. This is with the arrows 16 in the 1 shown. The currents flow in horizontal circles as well as in vertical circles. The fiber 4 is in this plasticized substance 17 introduced, with the fiber 4 by means of the welding pin 9 excited material flow of the matrix material of the parts to be joined 5 . 6 is detected by the circulating weld metal and is positioned flow-dependent or flow-dependent in the weld metal.

The welding pin 9 is while the rotating welding pin 9 in contact with the connection area 12 stands, linear along the connecting line 13 between the two plates 5 . 6 emotional. The connection area 12 is plasticized in the forward direction and the endless fiber 4 continuously to the plasticized area 17 fed. In the reverse direction, the connection area solidifies 12 again, so the fiber 4 in the welded seam 18 is frozen. Consequently, a component becomes 19 made of fiber-reinforced material, in which the seam 18 as well as the workpieces 5 . 6 fiber reinforced. Due to the flow-dependent or flow-dependent positioning of the fiber 4 in the weld metal can be a seam 18 be provided, in which the fiber 4 in the seam 18 has a helix shape. This is in the 3 shown.

The object 19 thus has two fiber-reinforced joining parts 5 . 6 on, over a welded seam 18 connected to each other. An endless fiber 4 with a helix shape is in the seam 18 arranged and extends along the longitudinal direction of the seam 18 , The object 19 has a fiber reinforced seam 18 as well as fiber-reinforced joining parts 5 . 6 and can be used as a component for an aircraft or a motor vehicle.

The inventive method provides a solid state welding of continuous fiber reinforced metals and plastics, in which at the same time a targeted fiber positioning is achieved in the weld metal. This has the advantage that not only the matrix materials are welded together. In conventional friction stir welding continuous fiber reinforced materials, the fibers in the contact area between the welding pin 9 and the parts to be joined 5 . 6 be severed so that the strength of the compound comes only from the organic or metallic matrix material. This strength is significantly lower than that of the fiber-reinforced material. This is avoided by the inventive targeted positioning of an additional fiber in the welded seam, so that the strength of the seam is increased and the welded component is more reliable and resilient.

Preferably, the shoulder rotates 8th not while the welding pin 9 rotates. Consequently, through the shoulder 8th no additional frictional heat is generated, but it merely ensures that through the shoulder 8th at the appropriate time, the required pressure is exerted on the material to be plasticized in the connection area. By doing that, the shoulder 8th During the friction stir welding process in a rotating sense "stuck" is both a higher speed of the welding pin 9 as well as a reduction of the through the shoulder 8th mediated process force possible, the latter in particular leads to a simplification of the system technology. In turn, the former results in a uniform temperature distribution over the entire thickness or the entire cross-section of the parts to be joined during the friction stir welding process 5 . 6 is guaranteed, so that they can be welded reliably and with high quality. The through the shoulder 8th otherwise caused frictional heat generation on the surface of the parts to be joined 5 . 6 is significantly reduced, which effectively prevents overheating on the surface.

According to an alternative embodiment of the friction stir tool according to the invention 2 can be dispensed with the molding. Then the direction towards the welding pin 9 facing side of the warehouse 10 as a shoulder. This is due to the reduced components a particularly simple embodiment. The function and operation of this alternative shoulder is the same as in the above-described, formed as a molded shoulder 8th ,

A Another alternative training of the molding allows it on the To refrain from stock.

1

contraption

2

friction stir

3

fiber source

4

fiber

5

first workpiece

6

second workpiece

7

tool body

8th

shoulder

9

welding pin

10

storage

11

Through opening

12

connecting area

13

connecting line

14

forward movement

15

rotation of the welding pin

16

Flow of weld

17

plasticized material

18

welded seam

19

object with welded seam

Claims (32)

Object ( 19 ) of at least one fiber-reinforced material with a welded seam ( 18 ), characterized in that a fiber ( 4 ) in the seam ( 18 ) is arranged. Object ( 19 ) according to claim 1, characterized in that the fiber ( 4 ) extends almost the entire length of the seam. Object ( 19 ) according to claim 1 or claim 2, characterized in that the fiber ( 4 ) has a helical shape. Object ( 19 ) according to one of claims 1 to 3, characterized in that a plurality of fibers ( 4 ) in the seam ( 18 ) are arranged. Object ( 19 ) according to claim 4, characterized in that the fibers ( 4 ) are confused with each other. Object ( 19 ) according to one of claims 1 to 5, characterized in that the object ( 19 ) is a component of an aircraft or a motor vehicle. A method of friction stir comprising the steps of: - inserting a rotationally driven pin-shaped projection ( 9 ) in a workpiece area or in a connection area ( 12 ) of at least two adjoining workpieces ( 5 . 6 ) with rotating movement, - plastification of the workpiece area or of the connection area ( 12 ) in at least one contact area ( 17 ) between the rotating projection ( 9 ) and the workpiece area or connecting area ( 12 ), and - introducing a fiber ( 4 ) in the plasticized area ( 17 ). Method according to claim 7, characterized in that a shoulder ( 8th ) on the workpiece area or connecting area ( 12 ) is applied under at least temporary pressurization, wherein during the projection ( 9 ) is in contact with the workpiece area or connecting area, the speed of rotation of the shoulder ( 8th ) n = 0. Method according to claim 7, characterized in that a shoulder ( 8th ) is applied to the workpiece area or connecting area under at least temporary pressurization, wherein during the projection ( 9 ) is in contact with the workpiece area or connecting area, the speed of rotation of the shoulder ( 8th ) greater than 0 and smaller than the rotational speed of the projection ( 9 ). Method according to one of claims 7 to 9, characterized in that the projection ( 9 ) in the workpiece area or connecting area ( 12 ) is moved linearly, the fiber ( 4 ) continuously into the plasticized area ( 17 ) is introduced. Method according to one of claims 7 to 10, characterized in that the projection ( 9 ) relative to the adjacent workpieces ( 5 . 6 ) along the connecting line ( 13 ) of the adjacent workpieces ( 5 . 6 ) is moved. Method according to one of claims 7 to 11, characterized in that the abutting workpieces ( 5 . 6 ) relative to the projection ( 9 ) along the connecting line ( 13 ) of the adjacent workpieces ( 5 . 6 ) are moved. Friction stir tool ( 2 ) comprising a rotationally drivable tool body ( 7 ) at the drive end facing away from a shoulder ( 8th ) is provided, from which in the direction away from the drive end of the tool body ( 7 ) a rotatable, pin-shaped projection ( 9 ), which has a smaller diameter than the shoulder ( 8th ), wherein the shoulder ( 8th ) and the pin-shaped projection ( 9 ) are independently driven in rotation, characterized in that the shoulder ( 8th ) at least one passage opening ( 11 ), which in the direction of the drive end facing away from the tool body ( 7 ). Friction stir tool ( 2 ) according to claim 13, characterized in that the shoulder ( 8th ) is designed such that upon rotation of the pin-shaped projection ( 9 ) has a speed n = 0. Friction stir tool ( 2 ) according to claim 13 or claim 14, characterized in that the shoulder ( 8th ) by means of sliding or roller bearings ( 10 ) on the tool body ( 7 ) is stored. Friction stir tool ( 2 ) according to claim 15, characterized in that the shoulder ( 8th ) is a molding which is in the direction of projection ( 9 ) facing side of the sliding or rolling bearing ( 10 ) is arranged. Friction stir tool ( 2 ) according to claim 16, characterized in that an edge portion of the molding is angled such that it is the sliding or roller bearing ( 10 ) at least partially surrounds. Friction stir tool ( 2 ) according to claim 16 or claim 17, characterized in that the molded part at least on its in the direction of projection ( 9 ) facing side is provided with a friction-reducing material. Friction stir tool ( 2 ) according to claim 13 or claim 14, characterized in that on the tool body ( 7 ) a sliding or rolling bearing ( 10 ) is arranged, whose at least in the direction of projection ( 9 ) side facing the shoulder ( 8th ). Friction stir tool ( 2 ) according to claim 19, characterized in that the projection ( 9 ) facing side of the sliding or rolling bearing ( 10 ) is provided with a friction-reducing material. Friction stir tool ( 2 ) according to one of claims 13 to 20, characterized in that the pin-shaped projection ( 9 ) in one piece with the tool body ( 7 ) is trained. Friction stir tool ( 2 ) according to one of claims 13 to 21, characterized in that the tool ( 2 ) is rotationally symmetrical. Friction stir tool ( 2 ) according to one of claims 13 to 22, characterized in that the passage opening ( 11 ) in the direction of the drive-away surface of the shoulder ( 8th ) expands. Friction stir tool ( 2 ) according to one of claims 13 to 23, characterized in that the passage opening ( 11 ) substantially perpendicular to the in the direction away from the drive surface of the shoulder ( 8th ). Friction stir tool ( 2 ) according to one of claims 13 to 23, characterized in that the passage opening ( 11 ) from the drive-facing surface of the shoulder ( 8th ) up to the one in the lead ( 9 ) facing away from the shoulder ( 8th ). Contraption ( 1 ) for friction stir, comprising a friction stir tool ( 2 ) according to one of claims 13 to 25, wherein the projection ( 9 ) in a workpiece area or a connection area ( 12 ) of at least two workpieces to be joined ( 5 . 6 ) is insertable under rotating movement, so that during its rotation in contact with the workpiece area or connecting area ( 12 ) the lead ( 9 ) this plasticized and plastified material (at least in the contact area) ( 17 ), characterized in that the device ( 1 ) a fiber source ( 3 ) and that a fiber ( 4 ) via the passage opening ( 11 ) in the shoulder ( 8th ) into the plasticized substance ( 17 ) is insertable. Contraption ( 1 ) according to claim 26, characterized in that the device ( 1 ) further comprising drive means, with which the device ( 1 ) under the rotary drive of the projection ( 9 ) can be performed linearly. Contraption ( 1 ) according to claim 26 or claim 27, characterized in that the shoulder ( 8th ) on the workpieces ( 5 . 6 ) outside the contact area between the projection ( 9 ) and the workpiece area or connecting area ( 12 ) can be applied. Use of the friction stir tool ( 2 ) according to one of claims 13 to 25 for welding fiber-reinforced plastics, fiber-reinforced metals or fiber-reinforced alloys. Use of the friction stir tool ( 2 ) according to one of claims 13 to 25 for welding two adjoining workpieces made of fiber-reinforced plastic, fiber-reinforced metal or fiber-reinforced alloys. Use of the device ( 1 ) according to any one of claims 26 to 28 for welding fiber reinforced plastics, fiber reinforced metals or fiber reinforced alloys. Use of the device ( 1 ) according to one of claims 26 to 28 for welding two adjacent workpieces made of fiber-reinforced plastic, fiber-reinforced metal or fiber-reinforced alloys.