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To assess the ability of a material to create filler metal flow and fill the brazing joint areas during the brazing process, we adapted a method which is called aluminum Flow Factor test. The target is to take benefit of this test in order to reach an optimum level of heat exchanger performance from project development steps. This paper studies similar aluminum clad material compositions coming from different suppliers. After brazing process, significant differences were noticed in the filler metal flow results. This study highlighted the impact of brazing peak temperature to create more or less flow of filler metal. The Flow Factor is promoted by the increase of brazing peak temperature. It also showed that regardless the material gage, at a low peak temperature of 591°C, Flow Factor are quite similar around 0,18.

Heat exchanger requires both high quality level and high performance. In order to manufacture heat exchanger, aluminium brazing technology is often used. Moreover to improve compactness and lightness, the material thickness of the heat exchanger components tends to decrease. However, it is necessary to maintain high quality level in particular regarding corrosion resistance. In order to improve the corrosion resistance of heat exchanger, several methods are used. One of the possibilities is to use multiclad material with a corrosion protection layer. Other methods propose to use a modified Nocolok flux. This modified Nocolok flux during melting creates zinc particles. The zinc particles react with the aluminium alloy surface during the brazing cycle and create an external layer with better corrosion resistance due to local corrosion potential modification.