Reduction, sintering, and hot rolling of preformed iron oxide superconcentrate strip

Abstract

AbstractMagnetite superconcentrate powder bonded into strip form was reduced at three different temperatures. Complete reduction of the strip was achieved at 1200°C resulting in a sponge iron strip containing about 75% porosity. It was found that the sponge iron strip could be hot rolled at 1130° C to a fully dense strip without significant edge cracking. In the initial stages of hot rolling, densification of the strip was brought about mainly by the physical movement of the sponge iron particles in the thickness direction. In the later stages of hot rolling strain was produced in the strip both in the thickness and longitudinal directions, and the sponge iron particles joined together to form a sinuous configuration. Plastic deformation subsequently became the main densification mechanism. A fine-grained strip having an ultimate tensile strength of about 300 MN m−2 coupled with an elongation of about 30% was obtained after a limited amount of hot rolling.