Abstract
The role of liquid phase and pressure on the densification mechanism of hot pressing of iron-carbon alloys in the presence of liquid phase was clarified and also a strengthening of the alloys was investigated. With an increase of the sintering temperature, both sintering of iron powder and diffusion of carbon into iron powder occurred simultaneously and then densification proceeded by an easy movement of solid phase under a constant pressure of 10 kg/cm2 in the presence of liquid phase above the solidus line.
After cooling, the bending strength of Fe-2%C alloy was decreased by the presence of cementite network. The alloys were strengthened by annealing at 1100°C for 3 hrs in a vacuum or by addition of 3%Cu or Ni. An Fe-3%Ni-1.7%C alloy made by this process provided a bending strength of 280 kg/mm2.
