The physical characteristics of nano-sized particles lead to lower melting and sintering temperatures than those of the corresponding bulk material. Thus, no melting point depressants such as boron or silicon in Ni braze fillers are required in order to achieve sufficiently low joining temperatures and the issue of brittle intermetallic phase formation can be avoided. In order to employ nanoparticles in joining applications, they have to be processed to suspensions, e. g. pastes. In this work a series of pastes with Nickel nanoparticles (Ni nanopastes) based on different mean particle diameters and different organic ingredients were prepared by using ultrasound-enhanced dispersing. With these pastes, samples are produced by inductive heating under vacuum, which are used for microstructural analysis and mechanical examinations. Results for processing properties and metal content are shown, as well as some joining strengths and microstructure of the joints.
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