| The resistance brazing of TiNi shape memory alloy using self-made resistance welding machine was realized successfully with the improved AgCl-KF-LiCl-AxBy flux matching CuNi filler metal foils, which has important actual meaning to widen the application fields of TiNi shape memory alloys.In this paper, based on the perpendicular test, the optimum brazing parameters were obtained. On the conditions of welding heat power 6. 75kW, welding pressure 175N and welding time 5C with gas shielded, the shear strength is averagely up to 575MPa. Further detailed analysis of the resistance brazing parameters such as welding heat power, welding pressure and welding time with/without gas shielded in TiNi shape memory alloy resistance brazing showed that welding heat power had greatly effect on the shear strength of the brazed joint.The microstructures of the joint were analyzed using optical microscope, SEM and EDX measures. The intermetallic compound Ti:tNi^ was found in the brazed seam which is the key factor of double round shape memory effect and all round shape memory effect. At the same time, from the microstructure of brazed joint, no new precipitation was found in the welded base metal and the brazed joint had no obvious heat affected zone, which showed that welding heat had a little effect on base metal. The EDX results confirmed that the brazing process were accomplished well because elements of fillermetal foil are distributed equally and dispersedly, which could consolidate the brazed joint.
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