Deformation Study of Sintered Iron-Carbon-Silicon-Copper Steel Compacts during Cold Forging

Cylindrical preforms of 0.4 initial aspect ratio with 86 ± 1% initial theoretical density has been prepared for iron-0.8%carbon-1%silicon with 0.4% and 1.2% copper added steel preforms through classical powder metallurgy route. These preforms are then subjected to secondary deformation such as cold upsetting to evaluate the deformation characteristics. The cold upsetting is carried out in an incremental step of 0.04 MN under two different frictional media using 100 tons capacity hydraulic press. Plasticity theories have been portrayed for various stresses, strains and Poisson's ratio under triaxial condition. The results revealed that the compositional effect on deformation is quite evident under dry friction condition than at graphite employed lubricant condition; on the other hand, both the friction condition shows a phenomenal effect on densification characteristics. Further, it is found that increase of copper content and frictional condition proportionally increases axial and hoop stress but there is a nil effect on mean stress.