Electrical Contact Part and Method for Manufacturing an Electrical Contact Part

20230107114 · 2023-04-06

    Inventors

    Cpc classification

    International classification

    Abstract

    An electrical contact part comprising, a carrier substrate of a metallic material, a metallic coating applied to the carrier substrate, and a coating barrier material applied to the carrier substrate in a partial area of the carrier substrate, wherein the coating barrier material substantially prevents coating of the carrier substrate in the portion.

    Claims

    1-20. (canceled)

    21. Electrical connection comprising: an electrical contact part including: a carrier substrate of a metallic material, a metallic coating applied to the carrier substrate, and a coating barrier material applied to the carrier substrate in a partial area of the carrier substrate, wherein the coating barrier material substantially prevents coating of said carrier substrate in the partial area; and a metallic conductor wherein the contact part is welded to the metallic conductor in a connection area and wherein the partial area is arranged on a side of the contact part facing away from the connection area.

    22. The electrical connection of claim 21, wherein the coating barrier material is a fluid, in particular with a dynamic viscosity of between 0.1 mPas and 1000 mPas.

    23. The electrical connection according to claim 21, wherein the coating barrier material is liquid or paste form.

    24. The electrical connection according to claim 23, wherein the coating barrier material is hydrophobic.

    25. The electrical connection according to claim 21, wherein the coating barrier material is bonded to the carrier substrate by means of adhesion or cohesion.

    26. The electrical connection according to claim 21, wherein the coating barrier material is an organic material, in particular a lipid.

    27. The electrical connection according to claim 21, wherein the coating barrier material is a silicone material or an inorganic material, in particular a lacquer.

    28. The electrical connection according to claim 21, wherein the coating barrier material is electrically non-conductive.

    29. The electrical connection according to claim 21, wherein the metallic coating is applied wet-chemically, in particular galvanically.

    30. The electrical connection according to claim 21, wherein the carrier substrate is coated in the connection area with a material which is thinner than the carrier substrate, in particular with sheet metal, strap or foil, wherein the partial area lies within the connection area, and wherein the carrier substrate and parts of the connection area are coated with the metallic coating.

    31. The electrical connection according to claim 21, wherein in the connection area the contact part is connected to the metallic conductor by material bonding.

    32. Method of manufacturing an electrical connection comprising: providing a carrier substrate of a metallic material; applying a coating barrier material to the carrier substrate in a partial area of the carrier substrate; applying a metallic coating to the carrier substrate to make a contact part, wherein the coating barrier material substantially prevents coating of said carrier substrate in said partial area; placing the contact part onto a joining tool with the coating barrier material; and materially bonding an electrical conductor to a side of the carrier substrate facing away from the coating barrier material.

    33. Method according to claim 32, wherein the carrier substrate is coated in a connection area with a material which is thinner than the carrier substrate, in particular with sheet metal, strap or foil, the partial area lying within the connection area, and that the carrier substrate and parts of the connection area are coated with the metallic coating.

    34. Method according to claim 32, further comprising removing the coating barrier material after the metallic coating, in particular is evaporated, in particular with a radiation source.

    35. Method according to claim 32, wherein after the metallic coating, the contact part is separated from the carrier substrate, in particular cut or punched.

    36. Method according to claim 32, wherein the coating barrier material is continuously applied to the carrier material via a nozzle.

    37. Method according to claim 32, wherein the coating barrier material is applied to the substrate in liquid or paste form.

    38. Method according to claim 32, wherein applying a metallic coating comprises wet-chemically metallically coating, in particular electroplating.

    Description

    [0038] In the following, the subject matter is explained in more detail with reference to a drawing showing embodiments. In the drawing show:

    [0039] FIG. 1a-d the coating of a contact part according to embodiments;

    [0040] FIG. 2a-c the coating of a contact part according to embodiments;

    [0041] FIG. 3a-e the manufacturing of a connection between a contact part and a conductor according to embodiments;

    [0042] FIG. 4a a schematic view of a tool for coating a contact part;

    [0043] FIG. 5a the arrangement of a contact part on an anvil according to embodiments;

    [0044] FIG. 5b the ultrasonic welding of a contact part to a conductor according to embodiments.

    [0045] FIG. 1 shows a carrier substrate 2, which is provided as a flat part. The carrier substrate 2 extends along a longitudinal axis X. The carrier substrate 2 has two opposing wide surfaces 2a and two opposing narrow surfaces 2b, and is thus formed in a cuboid shape. The carrier substrate 2 preferably extends for a greater length in the longitudinal direction X than in any axis transverse to the longitudinal extension X. The carrier substrate 2 is formed from a copper material or an aluminium material. The carrier substrate 2 is preferably provided in a quasi-continuous process, preferably moving in the direction of the longitudinal extension X. It is also possible that the carrier substrate 2 is provided individually as a rod-shaped component.

    [0046] In a subsequent step, as shown in FIG. 1b, a coating barrier material 4 is applied to the carrier substrate 2 on at least one broad surface 2a. The partial area to which the coating barrier material 4 is applied preferably also extends along the longitudinal extent X of the carrier substrate 2. On the wide surface 2a, the coating barrier material 4 extends in a width extent in the range between 10% and 70% of the width extent of the wide surface 2a.

    [0047] The coating barrier material 4 is preferably applied to the wide surface 2a in liquid or paste form in a preferably quasi-continuous process.

    [0048] After the carrier substrate 2 has been coated with the coating barrier material 4, a metallic coating of the carrier substrate is carried out. The result of the metallic coating can be seen in FIG. 1c. The metallic coating 6 is applied circumferentially to the carrier substrate 2. Here, in particular, a wet-chemical coating process, for example an electroplating process, can be carried out. In this coating process, a metallic material 6 is deposited on the surface of the carrier substrate 2. This may be, for example, tin, zinc, nickel or the like.

    [0049] The coating barrier material 4 prevents the metallic coating 6 from being deposited in the partial area in which the coating barrier material 4 rests on the carrier substrate 2. This can be achieved, for example, by the coating barrier material 4 being formed from a hydrophobic material. Thus, in the wet chemical process, the coating material 6 cannot be deposited on the surface of the carrier substrate 2 to which the coating barrier material 4 is applied.

    [0050] After coating, the carrier substrate 2 is present coated with a coating material 6, wherein in the area of the coating barrier material 4 this coating material 6 is not applied. After coating with the coating material 6, the carrier substrate 2 is singulated so that singulated contact parts 8 are formed, as shown in FIG. 1d. Here, a contact part 8 can be produced from the carrier substrate 2 by means of cutting or punching. In addition to cutting the contact part 8 out of the carrier substrate 2, it can be shaped so that the contact part 8 is formed as a cable lug, terminal lug, terminal lug, crimp cable lug or the like.

    [0051] Another way of manufacturing contact parts 8 is shown in FIGS. 2a-c. In FIG. 2a, the carrier substrate 2 is shown after coating with the coating barrier material 4 according to FIG. 1b.

    [0052] Before coating with the coating material 6, the carrier substrate 2 is separated and precursors 8′ of the contact parts 8 are manufactured. Here, the singulation can be carried out according to the explanations for FIG. 1c. The precursors 8′ are present, for example, as bulk material as shown in FIG. 2b. On the respective precursors 8′, the carrier substrate 2 is coated in each case with the coating barrier tool 4.

    [0053] The precursors 8′ are fed to a coating process, which can be carried out in accordance with the coating according to FIG. 1c. As a result of the fact that the precursors 8′ are already singled, a completely circumferential coating with the coating material 6 is achieved, whereby also the cut edges which arise during singling of the carrier substrate 2 into the precursors 8′ are coated with the coating material 6. Here, too, the carrier substrate 2 remains free of the coating material 6 in the area of the coating barrier material 4.

    [0054] FIGS. 3a-e show a cross-section perpendicular to the longitudinal axis X of the carrier substrate 2. In FIG. 3a, it can be seen that the carrier substrate 2 has a rectangular cross-sectional profile. It should be noted that any cross-sectional profiles of carrier substrate 2 are useful and conceivable. In particular, such cross-sectional profiles are useful which have at least one straight extending edge.

    [0055] Preferably on the surface of the carrier substrate 2 formed by the straight edge and the longitudinal axis, a metallic inlay 10 is applied as shown in FIG. 3b. The inlay 10 can be provided as a sheet or strip, in particular in foil form. The inlay 10 can also be applied to the carrier substrate 2 by friction welding. The inlay 10 is made of a metallic material, which is in particular different from the metallic material of the carrier substrate 2. The material combination of aluminium and copper is preferred here, whereby alloys of these metals can be meant in each case.

    [0056] At the transition between the inlay 10 and the carrier substrate 2, increased contact corrosion is to be fearexpected, so that this transition must be protected. On the other hand, the inlay 10 is to be used to contact the contact part 8 with a component and thus the bare metal of the inlay 10 should be available at the inlay 10.

    [0057] To achieve this, it is proposed that along the longitudinal extension of the inlay 10 in a width extension smaller than the inlay 10 and spaced apart from a transition between the inlay 10 and the supporting substrate 2, the coating barrier material 4 is applied, as shown in FIG. 3c. The coating barrier material 4 may be according to the above embodiments and, in particular, may be applied by means of a nozzle.

    [0058] After the coating barrier material 4 is applied, the metallic coating 6 is applied to the carrier substrate 2 according to FIG. 1c or 2c, as shown in FIG. 3d. A central region of the inlay 10, where the coating barrier material 4 has been applied, remains free of the coating material 6.

    [0059] Subsequently, the coating barrier material 4 can be removed by suitable methods, such as laser cleaning. Also, the coating barrier material 4 can be washed out, for example in an alcoholic solution.

    [0060] After the coating barrier material 4 has been removed, or through the coating barrier material 4, an electrical conductor 12 can be secured to the inlay 10 by a material bond. This can be done, for example, by friction welding, ultrasonic welding, resistance welding, or the like.

    [0061] The connection of the conductor 12 to the bare metal of the inlay 10 is shown in FIG. 3e. For example, if the conductor 12 is made of aluminium material, the inlay 10 may be formed of aluminium material. If the conductor 12 is made of a copper material, the inlay 10 may be formed of a copper material. In this case, the carrier substrate 2 is different from the material of the inlay 10, for example in the first case from a copper material, in the second case from an aluminium material.

    [0062] FIG. 4 shows how the carrier substrate 2 is unwound from a coil 14 and continuously fed to a coating device 16. The carrier substrate 2 is moved along its longitudinal axis X past the coating device 16. Here, as shown in FIGS. 1b and 2a, a coating barrier material 4 is applied, for example sprayed, to the wide surface 2a of the carrier substrate 2.

    [0063] Subsequently, the carrier substrate 2 is fed to a punch 18. The punch 18 punches out the precursors 8′ from the carrier substrate 2. The punched precursors 8′ are fed to a wet-chemical coating process 20, where they are coated with the metallic coating 6 so that the contact parts 8 are formed as shown in FIG. 2c.

    [0064] Due to the coating barrier material 4, the carrier substrate 2 is free of the coating material 6 in a certain area of its broad surface 2a. This can be used not only to make a pure connection between an electrical conductor 12 and the carrier substrate 2 via an inlay 10, as shown in FIG. 3e, but also to increase the service life of a welding tool, for example an anvil of an ultrasonic welding tool.

    [0065] In known processes in which a coated component is welded, the coating material 6 lies directly against an anvil and leads to increased wear on the latter. For the present, the contact part 8 with the coating barrier material 4, in particular the surface of the carrier substrate 2 which is free of the coating material 6, can be placed on an anvil 22, as shown in FIG. 5a. The anvil 22 may have a relief-shaped surface to provide increased adhesion of the contact part 8 to the anvil 22. This relief-shaped surface allows the coating barrier 4 to be pierced so that, despite the coating barrier 4 still remaining, the anvil 22 comes into direct contact with the carrier substrate 2. This is shown in FIG. 5a, in which the contact part 8 is brought to the surface of the anvil 22.

    [0066] As shown in FIG. 5b, the anvil 22 with its relief-shaped surface has penetrated the coating barrier tool 4 and is in contact with the pure material of the carrier substrate 2. An electrical conductor 12 can be applied to the coating material 6 on the opposite side, and a sonotrode 24 can be used to weld the conductor 12 to the contact part 8 in the area of the metallic coating 6. The vibration introduced causes the conductor 12 to be welded to the coating material 6. As a result of the anvil 22 not coming into contact with the coating material 6, its service life can be increased.

    LIST OF REFERENCE SIGNS

    [0067] 2 carrier substrate [0068] 4 coating barrier material [0069] 6 coating material [0070] X longitudinal axis [0071] 8 contact part [0072] 8′ precursor [0073] 10 inlay [0074] 12 electrical conductor [0075] 14 coil [0076] 16 coating device [0077] 18 punch [0078] 20 coating device [0079] 22 anvil [0080] 24 horn