Segregation in bimetallic alloys and its influence on wetting on a positive temperature coefficient resistor BaTiO3 ceramic

Bimetallic alloys have been considered in terms of their wetting behavior on semiconducting BaTiO3. In an earlier study, wetting behavior was strongly linked to ohmic contact behavior. However, the wetting behavior does not always correlate in the form of high work of adhesion-low contact resistance. The departure from this trend is associated with the nature of the segregation of the solute. Two extreme cases are considered in this study: no driving force for segregation and a strong driving force. These cases are characterized with sessile drop experiments and qualitatively analyzed in terms of thermodynamic analysis, both a surface enrichment model is considered together with an energy diagram approach. Both models give excellent qualitative agreement to the observed wetting behavior of the bimetallic alloy-BaTiO3 system.