Improvement of Mechanical Properties of Fe-Cr-Mo-[Cu-Ni]-C Sintered Sintered Steels by Sinter Hardening
Artikel i vetenskaplig tidskrift, 2011
The effect of high temperature sintering and high cooling rate on shifting the
microstructural composition to the favourably of martensite-bainite structures and thus effective
improvement of mechanical properties of sintered steels based on Astaloy CrL powder with an
addition of 1 and 2% Cu or 50% Distaloy AB powder and 0.65% C was investigated. All the
systems were processed by both sinter-hardening and conventional sintering. The vacuum sintering
at high-temperature of 1240 0C and at common temperature of 1180 0C were integrated with high
(6 0C/s), medium (3 0C/s) and slow (0.1 0C/s) cooling rates; conventional sintering at 1180 0C with
cooling rate of ~0.17 0C/s was carried out in a N2+10%H2 atmosphere. In dependence on chemical
composition, the yield and tensile strengths of 890-1150 MPa and 913-1230 MPa respectively and
impact energy of 10-15 J were achieved by sinter-hardening. The yield and tensile strengths are
approximately double than those resulting from conventional sintering.
microstructure
fractography
mechanical properties
sinter-hardening
Sintered steels