STRUCTURAL AND MECHANICAL PROPERTIES OF BRAZED JOINTS OF STAINLESS STEEL AND ALUMINIUM

Development of metals and alloys joining technology in modern scopes of industry is largely related to research of new technology of joining the materials of different physical and chemical properties. It deals with joining of stainless steel with lights metals as aluminum and its alloys. Obtaining the good quality and the high strength joints of this type is actually important technological and research problem. These properties are largely dependant of the appearance of brittle intermetallics in form of layers. Brazing is one of fundamental methods of performing these joints. In this publication the brazeability of composition stainless steel - aluminum is characterized and previous research attainment in the scope of brazing of this composition is discussed. There are also presented the results of investigation carried out in Institute of Welding in Gliwice. These investigations were conducted using the method of brazing with different rate of heating e.g. induction brazing in air (quick) and furnace brazing in argon atmosphere (slow). The filler metals of near eutectic composition AI-Si without alloying elements and with Ni and Cu were used. For all brazing joints the results of shear strength depended on holding time in brazing temperature and the results of structure analysis with kinetic of formation brittle phases are presented. The obtain results of investigation made it possible to select the best technological conditions of brazing of stainless steel and aluminum.