Electrical connection

A process of manufacturing an electrical connection, the electrical connection including a bushing having a cylindrical cross-section with an external circumferential surface having an outer diameter and a geometric central axis, an electrical conductor passing through the bushing along the geometric central axis, and an insulating layer electrically insulating the bushing from the electrical conductor, the process comprising steps of:

• providing at least a part of the external circumferential surface of the electrical conductor with protrusions and recesses having an arithmetic average roughness of at least Ra=1 μm;
• arranging the insulating layer concentrically within the bushing, and arranging the electrical conductor concentrically within the insulating layer thereby covering the protrusions and recesses of the external circumferential surface of the electrical conductor with the insulating layer;
• and
• pressing the bushing, the insulating layer and the electrical conductor together radially during a rotary forging process to mechanically join the bushing, the insulating layer and the electrical conductor by cold transformation of the bushing and the insulating layer, wherein during the rotary forging process radial pressure acts in a radial direction onto the external circumferential surface of the bushing thereby decreasing the outer diameter of the bushing and transferring at least part of the radial pressure to the insulating layer causing the insulating layer to flow into the recesses to mechanically join the insulating layer and the electrical conductor.