Influence of joint topology on the formation of brazed joints

This paper discusses the influence of joint topology on the formation of brazed joints. For the purposes of this study, the joint topology is defined by dimensionless parameters that characterize: (i) the geometry of the mating surfaces (shape and configuration), (ii) the gap between bonded parts (clearance and tolerances), (iii) the joint orientation in the gravity field and (iv) the volume of the joint. The influence of these parameters is presented for several joints with a topology that is typically found in the manufacture of compact heat exchangers. The results were obtained by employing a method that is based on a variational principle and minimization of the potential energy of the molten aluminium liquid metal just prior to the onset of solidification. The method, which was verified by comparison with experimental data obtained from controlled atmosphere brazing of aluminium alloys, is discussed in an accompanying paper.