LASER WELDING METHOD FOR JOINING A NON-SINTERED MATERIAL TO A SINTERED MATERIAL, COMPOSITE BODY, AND USE OF A LASER WELDING METHOD

Abstract

A laser welding method for joining a non-sintered material to a sintered material is disclosed. The method includes the steps of providing a first component made of a non-sintered material, providing a second component made of a sintered material, arranging the first component and the second component along a contact plane to produce a joining joint, applying a laser beam to a first joining region of the first component in the region of the joining joint to melt the first joining region to a melt, melting a second joining region of the second component in the region of the joining joint by means of the melt of the first joining region, and cooling the joining joint.

Claims

1. A laser welding method for joining a non-sintered material to a sintered material, the method comprising the steps of: – providing a first component comprising a non-sintered material, – providing a second component comprising a sintered material, – arranging the first component and the second component along a contact plane such that a joining joint is produced, – applying a laser beam to a first joining region of the first component in a region of the joining joint so as to melt the first joining region to a melt, – melting a second joining region of the second component in the region of the joining joint by means of the melt of the first joining region, and – cooling the joining joint.

2. The laser welding method according to claim 1, wherein the step of applying a laser beam further comprises the step of aligning the step of applying a laser beam further comprises the step of aligning the laser beam parallel to the contact plane.

3. The laser welding method according to claim 1, wherein the step of applying a laser beam further comprises the step of aligning the laser beam at an angle α to the contact plane, wherein the angle α is at least one of at most 45°, at most 30°, and at most 15°.

4. The laser welding method according to claim 1, wherein the step of applying a laser beam further comprises the steps of applying the laser beam by means of a continuous or a pulsed laser beam.

5. The laser welding method according to claim 1, wherein the step of applying a laser further comprises the step of applying the laser by means of laser beam MSG hybrid welding.

6. The laser method according to claim 1, wherein: • the step of providing of the first component further comprises the step of providing the first component by means of a first component made of steel, and • the step of providing the second component further comprises the step of providing the second component by means of a second component made of a carbon-containing sintered steel.

7. The method according to claim 1, wherein: • the step of providing the first component further comprises the step of providing the first component by means of a circular disc-shaped component, and • the step of applying the laser beam further comprises the step of applying the laser beam by directing the laser beam from radially outside onto the first joining region and guiding the laser beam on a circular path parallel to the contact plane and around at least one of the components.

8. A composite body, comprising: • a first component comprising a non-sintered material: and • a second component comprising a sintered material, and • wherein the first component and the second component are arranged along a contact plane such that a joining joint is produced. • wherein the first joining region is melted to a melt. • wherein a second joining region of the second component in the region of the joining joint is melted by means of the melt of the first joining region, and • wherein the joining joint are cooled.

9. The composite body according to claim 8, wherein the first component is configured in a shape of a circular disc.

10. The composite body according to claim 8, further comprising at least one groove formed parallel to the joining joint, wherein the groove is formed recessed in one of the first component and the second component.

11. The composite body according to claim 8, wherein the first component is configured as at least one of a cover and stator cover on a camshaft adjuster.

12. Body according to claim 8, wherein the second component is configured as at least one of a stator and a stator of a camshaft adjuster.

13. Body according to claim 8, wherein the sintered material is at least one of a sintered metal and a sintered steel.

14. The composite body according to claim 8, wherein the non-sintered material is at least one of a metal and a steel with a carbon content of at most 0.2%.

15. The composite body according to claim 8, wherein the sintered metal comprises a carbon content between at least one of 0.3 and 0.9 percent, 0.5 and 0.8 percent, and 0.6 percent.

16. (canceled)

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0037] Further advantages, features, and details of the various embodiments of this disclosure will become apparent from the ensuring description of a preferred exemplary embodiment and with the aid of the drawings. The features and combinations of features recited below in the description, as well as the features and feature combination shown after that in the drawing description or in the drawings alone, may be used not only in the particular combination received, but also in other combinations on their own, without departing from the scope of the disclosure.

[0038] The invention is explained in more detail below with reference to the embodiments shown in the drawings, which depict:

[0039] FIG. 1 depicts a cross-section of a first embodiment of a composite body according to the invention before applying a laser beam;

[0040] FIG. 2a depicts cross-section of the composite body of FIG. 1 during the application of a laser beam;

[0041] FIG. 3a depicts perspective view of a second embodiment of the composite body according to the invention during the application of a laser beam; and

[0042] FIG. 4a depicts flow chart of the method according to the invention.

DETAILED DESCRIPTON OF THE INVENTION

[0043] As used throughout the present disclosure, unless specifically stated otherwise, the term “or” encompasses all possible combinations, except where infeasible. For example, the expression “A or B” shall mean A alone, B alone, or A and B together. If it is stated that a component includes “A, B or C”, then, unless specifically stated otherwise or infeasible, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C. Expressions such as “at least one of” do not necessarily modify an entirety of the following list and do not necessarily modify each member of the list, such that at least one of “A, B, and C” should not be understood as including only one of A, only one of B, only one of C, or any combination of A, B, and C.

[0044] FIG. 1 shows a cross-section of a first embodiment of a composite body 1 according to the invention before applying a laser beam 11. The composite body 1 is in an early phase of a method according to the invention for its manufacture or of a laser welding method according to the invention for joining a non-sintered material and a sintered material. The first component 2 is made of a non-sintered material and the second component 3 is made of a sintered material. In addition, FIG. 1 shows a laser device 4 which is directed towards the first component 2. The components 2, 3 are located on opposite sides of a contact plane 5 along which they are arranged and thus placed against each other. The first component 2 comprises a first joining region 6. The second component 3 comprises a second joining region 7.

[0045] The joining regions 6, 7 are each arranged at the ends of the components 2, 3 facing the laser device 4. The components 2, 3 are arranged along the contact plane 5 and a joining joint 8 is created by means of the joining regions 6, 7. Thereby, the joining joint 8 is arranged along a joint edge. The joint edge extends where the components 2, 3 are flush with each other on the contact plane 5. The joining regions 6, 7 can also each have a groove 9, 10. Specifically, in the example shown, the first joining region 6 has a first groove 9 and the second joining region 7 has a second groove 10. The grooves 9, 10 are arranged opposite to each other and define a common cavity. The functions of the grooves 9, 10 are explained in the following description of FIG. 2.

[0046] FIG. 2 shows a cross-section of the composite body 1 of FIG. 1 during the application of a laser beam 11. Compared to FIG. 1, the composite body 1 is shown in an advanced phase of its manufacturing process. As in FIG. 1, the components 2, 3 with their joining regions 6, 7 and grooves 9, 10 can also be seen here. Furthermore, FIG. 2 again shows the laser device 4 and the contact plane 5. However, the components 2, 3 are now located on the contact plane 5 and are thus directly adjacent to each other, generating the joining joint 8. In addition, the laser device 4 is activated in this phase of the process, shown with a laser beam 11 directed towards the first component 2 respectively its joining region 6. Specifically, the process step of applying the laser beam 11 to the first joining region 6 of the first component 2 in the area of the joining joint 8 to melt the first joining region 6 to a melt is shown here. A subsequent respectively resulting process step is the melting of the second joining region 7 of the second component 3 in the area of the joining joint 8 by means of the melt of the first joining region 6. The result is an essentially circumferential welding seam.

[0047] The grooves 9, 10 are recessed in the respective component 2, 3 and are arranged on the common contact plane 5 and at least partially parallel to the joining joint 8. Since the two grooves 9, 10 are directly opposite to each other at the contact plane 5, they form a common cavity. The stress on the welding seam can be reduced because during operation of the composite body 1 pressure can be kept away from the welding seam root and dissipated into the surrounding base material.

[0048] It is also possible to provide a first respectively a second groove 9, 10 recessed in the first and/or the second component and extending at least partially parallel to the joining joint for gas pressure compensation. This has the advantage, for example, that the melt is less influenced by the diffusion of produced gases, whereby the strength can be additionally increased respectively stabilised. Furthermore, an improved shear strength of the joint can be provided by the flow of the melt into the groove. Furthermore, tensions during the joining process can be significantly reduced, which additionally improves the quality of the welded joint.

[0049] Moreover, only one of the grooves 9, 10 can be provided, i.e. either only the first groove 9 or only the second groove 10. Joining the components 2, 3 without any groove is also part of the invention.

[0050] When the laser beam 11 is applied to the first joining region 6, the laser beam 11 is aligned at an angle α to the contact plane 5. In this case, the angle α is specifically 15°. Optimally, the laser beam 11 is aligned parallel to the contact plane 5 or with α = 0°, as the laser beam 11 can then develop its maximum effect and penetration effect. However, the angle α can be up to 45° in order to achieve a sufficient effect of the laser beam 11. In principle, three-dimensional stress and heat dissipation states should be avoided.

[0051] FIG. 3 shows a perspective view of a second embodiment of the composite body 1 according to the invention during the application of a laser beam 11. In this second embodiment, the composite body 1 is shown as part of a camshaft adjuster. The composite body 1 is shown in the advanced phase of its manufacturing process as illustrated in FIG. 2. As in FIG. 2, the first component 2 and the second component 3 can be seen resting against each other along the joining joint 8. The first component 2 is configured as a circular disc-shaped stator cover and is made of a steel with a low carbon content. The second component 3 is formed as a stator of the camshaft adjuster and is made of a sintered steel with a carbon content of 0.6 percent. The selected carbon content of 0.6 percent ensures sufficient hardenability of the sintered steel of the second component 3, but at the same time still allows joining of the components 2, 3 by means of the laser welding method according to the invention.

[0052] In addition, FIG. 3 again shows the laser device 4 with the laser beam 11. When applying the laser beam 1, in this embodiment the laser beam 11, and thus also the laser device 4, are guided on a circular path 12 around the first component 2 or the stator cover. Thereby, the laser beam 11 is directed respectively applied to the first component 2 from radially outside. However, the invention is not limited to a circular welding seam. For example, the first component 2 can have a shape that deviates from the circular shape in order to prevent the component 2 from inflating, among other things. For example, the component 2 can be clo-verleaf-shaped so that the circumferential welding seam extends on several radii and extends partially radially. It is also conceivable that several circumferential welding seams are provided which extend separately from each other.

[0053] For simplification, the illustration of some details (such as contact plane and joining regions) was omitted in FIG. 3. However, the corresponding explanations for FIGS. 1 and 2 also apply here.

[0054] FIG. 4 shows a flow chart of the method according to the invention. The method comprises, after providing a first component 2 made of a non-sintered material and providing a second component 3 made of a sintered material, a first step of arranging 100 the first component 2 and the second component 3 along a contact plane 5 to produce a joining joint 8. In a second step, the method comprises applying 200 a laser beam 11 to a first joining region 6 of the first component 2 in the region of the joining joint 8 in order to melt the first joining region 6 to a melt. In the following process step, melting 300 of a second joining region 7 of the second component 3 takes place in the region of the joining joint 8 by means of the melt of the first joining region 6, and in the last step, cooling 400 of the joining joint 8 takes place.

[0055] All features explained and shown in connection with individual embodiments of the invention may be provided in different combinations in the subject matter according to the invention in order to simultaneously realise their advantageous effects.

[0056] Since the devices and methods described in detail above are examples of embodiments, they can be modified to a wide extent by the skilled person in the usual manner without departing from the scope of the invention. In particular, the mechanical arrangements and the proportions of the individual elements with respect to each other are merely exemplary. Some preferred embodiments of the apparatus according to the invention have been disclosed above. The invention is not limited to the solutions explained above, but the innovative solutions can be applied in different ways within the limits set out by the claims.