Abstract
The effect of addition of 20%Fe-70%Ni-10%B master alloy powder on the sintering behavior, microstructure and mechanical properties of atomized iron powder compacts has been studied.
The results are summarized as follows.
(1) The Fe-Ni-B master alloy profoundly activated the sintering process through the formation of eutectic liquid. Rapid densification occurred above 1403 K. Densities of the order 99% theoretical were readily achieved with 2% addition.
(2) Sintered strength increased with the amount of master alloy powder. With 5% additive, the tensile strength of 400 MPa was obtained. Maximum elongation of 33% occurred at 2% addition.
(3) Elongation was closely related to the eutectic phase and decreased as the brittle intermetallic phase became continuous.
(4) The sintering process of this work could be treated as traditional persistent liquid phase sintering. The volume fraction of liquid necessary for full density was 8%.
