Aqueous colloidal processing of nickel powder

Abstract Nickel micronic powders are processed by a colloidal route using aqueous suspensions. The optimum amount of dispersant is selected by means of rheological tests. The slurries show a plastic behaviour that retards sedimentation. Dispersed slurries are mixed with a gelling agent (κ-carrageenan) and cooled in order to provide the sample with strength enough for handling. Dynamic and static sintering studies are performed on green samples at temperatures ranging from 700 to 1400°C in flowing argon atmosphere. Porous and dense materials fabricated by this route are characterized by SEM and mercury porosimetry.