Abstract:
Microstructure development and mechanical property of SCr420 low-alloy steel
(equivalent to AISI 5120) obtained by the forging process have been investigated. The
relationship between the forgeability and mean grain sizes were examined. The type of forging
was carried out by die-forging at a temperature of around 1150 - 1190°C using a machine tonnage
of 1600 tons capacity with 2 times forging variation. The high aspect ratio can be maintained
through the steel forming applied for piston rod by the hot forging process. Vicker's hardness
mechanical tests in initial and forged conditions were carried out at room temperature. The
results demonstrate that the Vickers hardness of initial condition of 254.5 HV is much higher in
comparison with the hot-forged material of 152.6 HV. The forged low-alloy steel processes the
desired ferrite-pro eutectoid and pearlite microstructures, when followed by normalizing process,
and deformation are achieved.