Effect of Y2O3e-MgO addition on heterogeneous precipitation-thermal reduction synthesis and the sintering of Fee Mo/Si3N4 powders has been investigated. It was found that the whiskers-like b-Si3N4, good wettability phases on Si3N4 surface, and high toughness Fe phase appeared in Fee Mo/Si3N4 cermets with Y2O3-MgO additives. The results show that Y2O3-MgO additives can effectively optimize the microstructures of Fee Mo/Si3N4 cermets, and improve the material mechanical properties. Therefore, it indicated that Y2O3-MgO additives can be used for strengthening of sintered cermets, and the dual function of whiskers self-toughening and different metal-composition toughening can be achieved in Fee Mo/Si3N4 cermets with Y2O3-MgO additives.
