The constant feeding (PUSH and PULL) of the welding wire also promotes the uniformity of the arc and thus achieves a better welding result.
Welded pieces of metal are highly resilient; however, only metals that conduct electricity can be electrically welded. For this reason, CMT Pin is a proven welding process for joining metals to non-metallic materials such as plastic. Fronius has succeeded in developing an innovative solution: the CMT PIN (CMT = Cold Metal Transfer) welding process relies on arc welding to join the different materials.
The Fronius CMT welding process welds pins with spherical heads that project beyond the shaft diameter of the pin – similar to a mushroom – onto a metal surface. The “burred surface” created in this way serves as the contact and bonding basis for the metal. This is then potted with plastic, for example, to cover the pins. The potted spherical heads give the joint additional resistance against the separation of the two types of material. The pins are approximately 0.8 mm thick and only 3 mm long. If the plastic has elasticity, the joint can be undone like a Velcro® fastener. An adhesive bond offers up to ten-fold the force transmission of a conventionally bonded metal-plastic joint.
Additional solutions and types of joint are possible depending on the shape of the pins: