Abstract
The objective of the present work was mainly to study the pressing and sintering behavior of water atomized 17/25% Cr stainless steel powders containing Ni less than 20%.
The results were summarized as follows.
(1) Compressibility of powders got higher in proportion to an increase of Ni and a decrease of Cr, almost independently of phase constitution of particles.
(2) Compressibility was not improved by heat-decomposing a metastable (Delta-)ferrite which had been obtained during water-quenching, except the case where the α single-phase powder was annealed below 900°C.
(3) Green strength of compacts tended to be higher in an α-rich duplex phase range, mainly due to the roughness of surface of particles.
(4) Sinterability was appreciably affected by phase constitution of particles and in particular, proved to be higher in the α-rich duplex phase state in the case of Ni-varied 25%Cr steel powders.
