Because ultrasonic welding transmits ultrasonic waves to the metal surface, under pressure, the conductor surfaces rub against each other to form fusion between the molecular layers. If there is oil, oxidation, impurities, etc. on the surface of the conductor, the welding quality will be greatly affected.
Lubricant remaining on the surface of the monofilament. During the production of monofilaments before conductor stranding, the concentration of drawing fluid or annealing fluid should be controlled at the lower limit of the process range as much as possible to reduce the residual lubricating fluid on the surface of the monofilament. Usually the concentration of the drawing liquid is controlled at 5.5%, and the concentration of the annealing liquid is controlled at 0.5%, which can ensure that the copper single wire does not oxidize and at the same time reduce the residual lubricating liquid on the surface of the copper single wire to a minimum.