Wetting and micro-structural variations of nano-composite brazing fillers for dispenser cathode manufacturing

Wetting behavior and micro-structural variations of Mo-Ni brazing fillers doped by either Mo-Ni or SiC nano-particles were studied. It was noticed that an increase of nano-particle content dramatically impacts wetting as well as the modifications of micro-structural morphology after re-solidification. It is hypothesized that these changes lead to distinct responses of the composite fillers to macro-indentation established earlier. Mo-Ni near-eutectic fillers doped with 1%, 3% and 5% SiC nanoparticles, feature a decreasing trend of wetting ability. A similar behavior is established for homogeneous Mo-Ni composites (doped by Mo-Ni nano particles).