Yushchenko S. Development of precision joining technique of aluminium alloys

The thesis is devoted to development of solid phase welding technique of precision permanent joints of aluminium and alloys. The necessity of final product precision is the ensuring of residual deformation less than 2 % from its initial dimensions. Among existing welding methods of aluminium and alloys, pressure welding methods enable getting the precision, in particular, diffusion welding in vacuum and, in a number of occasions, resistance welding. At the same time getting of permanent joints is complicated by the presence of high-melting oxide film on the metal surface. Its removal before welding without using of complex techniques does not enable qualitative physical contact formation, thus conditions for getting precision joint deteriorate substantially. The formation of permanent joint during diffusion welding in vacuum occurs on the basis of welded surfaces activation by means of acceleration of physical contact formation. The permanent joint during resistance welding forms by force of thermal energy localization in the contact zone. New technology of diffusion welding in vacuum of aluminium and alloys with using of liquid eutectic interlayer has been developed. New technology of resistance butt welding of aluminium and alloys through thin aluminium foam interlayer has been developed