Cold Forming Response of IN861

Powder metallurgy cold forming processes provide several advantages: economy of material, minimal machining, close tolerances, high density and lower production costs. IN-861 is an air hardenable ferrous alloy of 2% Ni, 1% Mo, 0.7% Mn plus carbon produced from mixed elemental powders. Specimens were alloyed at three carbon levels and sintered at several temperatures in order to relate ductility and workability to alloy composition and preform sintering temperature. Results indicate that increasing carbon content and sintering temperature required increasing preform forming stresses. Also, ductility of the preform increased with increasing sintering temperature and decreasing carbon content. Further additions of manganese raise the forming stresses, however a marked reduction in ductility is noted. Additions of molybdenum appear to have little effect upon strength, but decrease the ductility. The results indicate the optimum processing conditions, e.g. composition and presintering temperature for workability and ductility of the IN-861 mixed elemental alloy system.