Abstract
Fe-48at%Cr alloy powders were synthesized by mechanical alloying (MA) of Fe powder and Cr powder using a planetary ball milling for 180ks under 1.33kPa argon gas atomosphere. In order to consolidate the MA powder at a lower temperature, 0.5-5.0mass%Al powders were mixed with the MA powder for 36ks by a planetary ball mill. The results of DSC indicated that Al powders were not reacted with mechanical alloyed powders and remained as primary powders. The obtained mixed powders were consolidated by spark plasma sintering (SPS) apparatus.
By the addition of Al, the starting temperature of the shrinkage of mixed powders during SPS was reduced to lower of 100-150K than that of mechanical alloyed powders. However, the sintered bodies containing more than 2.5mass%Al were brittle because of the formation of FeAl intermetallic compound during a sintering process. The sintered body which contained 0.5mass%Al had fine microstructure and the hardness of 350-370Hv.
