Material deformation in cold pressure welding

Cold welding is a pressure welding process that does not use thermal source to achieve the weld. The joint is possible due to a very important plastic deformation (a 70 % rate at least for aluminium), which creates the possibility of welding due to atomic interaction forces. This technique can be applied only to materials with a small value of yield strength, in order to have technical possibilities to ensure the force required. A number of considerations connected to the principle of butt cold pressure welding, especially concerning the process of plastic deformation and the forces requested by the process are presented. The real force requested for squeezing the parts in order to do the weld is smaller than that recommended by the theoretical studies (because of th