The sintering of an Fe–Cr–Ni–B–C powder

This paper describes the sintering of pre-alloyed Fe–Cr–Ni–B–C alloy components produced by metal injection moulding. The solidus temperature of this alloy was determined to be about 1150 °C and coincides with an increase in the sintering rate. At just 10 °C above the solidus, near full density is attained after 1 h. Initially, the hardness follows the same pattern as the density, however at temperatures above 1170 °C, the hardness decreases as a result of the coarsening of the borides. Despite the high hardness, the strength of this alloy was only moderate – a result of the low ductility.

Research highlights▶ Supersolidus liquid phase sintering of an Fe–Cr–Ni–B–C alloy studied. ▶ Sintering to near full density can be achieved at only 10 °C above the solidus temperature. ▶ High temperature or extended sintering time coarsens the borides, reducing the hardness of the material. ▶ Properties matching investment cast material can be achieved.