Author : Arnab Mandal 1
Date of Publication :11th May 2017
Abstract: Present investigation pertains to evaluate the densification mechanism and mechanical properties of sintered Fe, Fe-2.5%FeO and Fe-5.5%FeO during hot upsetting to disc and square cross-section bars. Compacts of initial aspect ratios of 1.18 and 1.31 were prepared from iron powder and blended Fe-2.5% FeO and Fe-5.5%Feo using suitable die, punch and bottom insert on 1.0 MN capacity U.T.M in the pressure range of 490 ± 10 MPa and 520 ±10 MPa respectively. These Compacts of each composition in the density range of 82±1 per cent of theoretical were sintered at 1150 ±100 C for a period of 120 minutes under the protective ceramic coating. Sintered compacts of 1.18 were axially hot upset forged to different height strains whereas the performs of 1.31 aspect ratio were forged to square cross-section (~13mm X ~13 mm) bars of approximate length of 100±5mm. Analysis of experimental data and calculated parameters revealed the existence of third order polynomial densification for both w.r.t height strain and poisson’s ratio. Addition of FeO in iron has raised the strength but show a substantial drop in ductility
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