Controlled atmosphere brazing ,

This is the case, for instance, for K2Sip6 which in an aluminothermic reaction provides in situ the Al-Si clad (molten fiUer metal) normally used for controlled atmosphere brazing (CAB) of aluminium. In the case of zinc, the primary objective is not only to form a clad but to obtain a homogeneous diffusion layer into the aluminium, which is needed for some applications and which would have to be otherwise applied by costly intensive methods like electrochemical galvanization, plasma coating or thermal spray coating. 

Controlled atmosphere brazing using non-corrosive potassium fluoroaluminate flux is the dominant process for making all aluminium heat exchangers. 

D. Childree, Fluxless brazing in a controlled atmosphere furnace with a new filler alloy containing Na, International Invitational Aluminum Brazing Seminar, Detroit, October 2000, conference proceedings. 

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