Aluminium and aluminium alloy hard soldering technology

Abstract

Aluminium joints find wide application in the welded structures of air conditioning systems, aeronautics, electrical engineering, radio engineering, and many other areas of industry. In spite of their unquestionable qualities, aluminium and aluminium alloy soldering brings about considerable setbacks, especially in the case of highly alloyed aluminium compounds. The problems result from the physical and chemical properties of such materials. For instance, highly alloyed aluminium requires specific solders of sufficiently low melting point, as well as special sources of heat in order to ensure even soldering. An additional problem results from the considerable aluminium-to-oxygen chemical affinity that produces the resultant Al₂O₃ layer on the surface as an integral and barely fusible coat. This article presents the problems related to aluminium and aluminium alloy joining as well as basic methods of aluminium soldering.