Why can’t ferrous materials be welded using cold pressure?
Materials which contain carbon cannot be joined by cold pressure welding. Carbon interferes with the flow of the material and stops the cold weld process taking place. (Trials have been carried out on low carbon steel wire, but even with this material, heat had to be introduced into the wire in order to lower its tensile strength and cause the material to flow together during the cold weld process.) There are cost and safety implications involved in incorporating a heating facility to a cold pressure welder, so it is more practical and cost-effective to use hot welding to join ferrous materials.
