Supersolidus liquid phase sintering of Inconel 718 powder alloy

Nickel base powder superalloy Inconel 718 was prepared from pre-alloyed powder by supersolidus liquid phase sintering. The results show that compacts with a relative density over 98% can be obtained by sintering at 1240℃ for 120 min in vacuum. The relative density of sintered samples could be increased to 99.7% by next hot isostatic pressing process. The tensile strength and ductility of heat-treated samples are 1 280 MPa and 9% respectively at room temperature. The precipitates are spherical γ' and needle γ' and coarse carbides, and the average grain size is below 50μm.