Aqueous colloidal processing of nickel powder

Nickel micronic powders are processed by a colloidal route using aqueous su spensions. The optimum amount of dispersant is selected by means of rheolog ical tests. The slurries show a plastic behaviour that retards sedimentatio n. Dispersed slurries are mixed with a gelling agent (kappa -carrageenan) a nd cooled in order to provide the sample with strength enough for handling. Dynamic and static sintering studies are performed on green samples at tem peratures ranging from 700 to 1400 degreesC in flowing argon atmosphere. Po rous and dense materials fabricated by this route are characterized by SEM and mercury porosimetry. (C) 2001 Acta Materialia Inc. Published by Elsevie r Science Ltd. All rights reserved.