Characterization of ultrasonic soldering of Ti and Ni with Ni/Al reactive multilayer deposition

Abstract

The joining of Ti and Ni at low temperatures was analysed in this work. For joining pure Ti and Ni coins of 1.5 mm in thickness were used. Reactive multilayer thin films/foils with nanometric period (bilayer thickness), in particular Ni/Al multilayers, have been used to promote joining in two thickness of 28 and 55 nm. The ultrasonic soldering with SnAgTi active solder has been used for “hard-to-solder” material. The structural evaluation of soldered joint was studied by optical microscopy and EDX analysis. The structural analysis was focused to the creation of intermetallic layers in the joint interface. The mechanical properties of solder joints were tested by shear strength.