Abstract
In Fe-X-C ternary system (X: carbide-forming element), high density ferrous sintered alloys were obtained by supersolidus hot pressing process. A relatively low pressure of 10 kg/cm2 was applied to mixtures of iron, graphite and carbide-forming element powders, which were heated to the range between solidus and liquidus lines of Fe-2%C in iron-cementite phase diagram. Tungsten or chromium was found to be the most effective to the mechanical properties as the third additive element. Further improvement in strength was obtained by the addition of the fourth element, Cu or Ni, due to strengthening of the matrix phase in the Fe-X-C alloy. For example, Fe-15%W-1%Cu-2.4%C alloy made by this process provided a bend strength of 300 kg/mm2 and a hardness of HRC 50. Addition of l%V, one of the fourth elements, made the wear resistance much improved.