Friction welding connector and its method of production

1 . A method for making an electrical connection by joining a first contact part to a second contact part in a material-to-material contact, the method comprising the steps of:

providing the first contact part comprising a male first joining section arranged towards the second contact part and being a solid, substantially cylindrical post defining the first joining section;

providing the second contact part comprising a female second joining section arranged towards the first contact part and comprising a hollow profile, the female second joining section comprising an interior surface;

inserting the first joining section into the second joining section, inserting a rotating friction welding tool through an opening at a distal end of the female second joining section, opposite the end at which the male first joining section is inserted, and bringing the tool into contact with an interior surface of the female second joining section while the male first joining section remains fitted in the female second joining section, thereby forming an internal annular weld interface between the solid male first joining section and the surrounding female second joining section;

moving the friction welding tool relative to at least one of the first contact part and the second contact part so as to generate welding energy for at least partially plasticizing at least one of a part of the first joining section and the second joining section facing an other contact part;

wherein a material of the first contact part has a lower mechanical strength or lower yield point than a material of the second contact part;

wherein the first contact part comprises aluminum or aluminum alloy, and the second contact part comprises copper, copper alloy, brass, or stainless steel; and

wherein the friction welding generates sufficient heat and relative mechanical displacement at said internal annular interface to disrupt aluminum oxide on the first joining section and to prevent reformation during bonding to the copper-containing second joining section.

2 . The method according to claim 1 , wherein the first contact part comprises at least one material recess formed in the first joining section.

3 . The method according to claim 2 , wherein the material recess extends along an axis of rotation of the first joining section.

4 . The method according to claim 2 , wherein the material recess is arranged on a lateral surface of the first joining section.

5 . The method according to claim 1 , wherein the at least one material recess is formed by a machining manufacturing process.

6 . The method according to claim 1 , wherein at least one of the first contact part and the second contact part comprises an electrical connection section in addition to the joining section and is configured to attach a further contact partner or contact part.

7 . The method according to claim 1 , further comprising the step of: attaching at least one further contact partner to an electrical connection section of at least one of the first contact part and second contact part.

8 . The method according to claim 1 , further comprising the step of: coating at least one of the first joining section and second joining section with an insulating material after melting of the same.

9 . The method according to claim 1 , wherein:

wherein the friction welding tool is inserted into an internal cavity of the second contact part and brought into contact with an interior wall thereof to generate welding energy sufficient to disrupt on the first contact part during joining.

10 . An electrical connection assembly, comprising:

a first contact part comprising a solid, substantially cylindrical male first joining section;

a second contact part comprising a female second joining section having a hollow profile within an interior surface and an opening at a distal end,

the male first joining section being received within the hollow sleeve profile; a metallurgical joint formed at an internal angular interface between the male first joining section and the surrounding female second joining section, the internal annular interface being located adjacent the interior surface and accessible via said distal opening;

wherein a material of the first contact part has a lower mechanical strength or lower yield point than a material of the second contact part;

wherein the first contact part comprises aluminum or aluminum alloy, and the second contact part comprises copper, a copper alloy, brass, or stainless steel, and

wherein the assembly is configured such that the metallurgical joint is producible by applying a friction welding tool through the distal opening into contact with the interior surface to generate welding energy sufficient to disrupt aluminum oxide and prevent its reformation during bonding to the copper-containing second joining section.

11 . The electrical connection assembly according to claim 10 , wherein the first contact part comprises at least one material recess formed in the first joining section, the material recess comprising an axial blind hore and/or a lateral recess configured to facilitate radial pressing and material flow during interior friction welding.

12 . The electrical connection assembly according to claim 10 , wherein an at least one material recess is formed by a machining manufacturing process.

13 . The electrical connection assembly according to claim 12 , wherein the material recess extends along an axis of rotation of the first joining section.

14 . The electrical connection assembly according to claim 12 , wherein the material recess is arranged on a lateral surface of the first joining section.

15 . The electrical connection assembly according to claim 10 , wherein at least one of the first contact part and the second contact part comprises an electrical connection section in addition to the joining section and is configured to attach a further contact partner or contact part.

16 . The electrical connection assembly according to claim 10 , further comprising at least one further contact partner configured to be attached to an electrical connection section of at least one of the first contact part and second contact part.

17 . The electrical connection assembly according to claim 10 , further comprising and insulating material coating at least one of the first joining section and second joining section with an insulating material after melting of the same.

18 . The electrical connection according to claim 10 ,

wherein the first joining section is joined to the second joining section by friction welding from within the second joining section via a tool engaging an internal surface of the second joining section.