Properties of rapidly solidified A1-Si base brazing filler alloys

Ribbons of A1-Si base brazing filler alloys, which are 26-37μm and 0.1-0.25mm thick,arc produced on rapid solidiflcation cquipmcnt with single-and double-roller respcctivcly.By using a Dupont 1090 differcntial scanning calorimctcr (DSC),the melting properties of the ribbons are studied.The results show that the liquidus temperature is reduced by 3 to 5℃ and the interval of crystallization temperature by about 20℃,As compared with the brazing filler alloys of conventional cast,the ribbons produced by rapid solidification show some flexibility which enables them to be used preferably in some cases,and the wetting coefficient and tensile strength of the ribbons are increased by 18 and 28.4 percent respectively.Mierostructures of the ribbons and the brazing scams are examined.Tensile strength of the joints brazed with brazing filler of rapid solidiflcation and of conventional cast are tested.Analysis of the above results show that the rapidly solidifled new brazing filler alloys have superior properties of lower melting point,higher strength, finer crystal structure,better wettability and less fluctuation of strength in the brazing joints.