Method for producing green compact and method for producing sintered body

A method for producing a metallic green compact having at least one recess, wherein the method comprises a step of subjecting a raw material powder filled in a resin mold to cold isostatic pressing while placing a resin core material having a shape corresponding to the recess at a position corresponding to the recess in the resin mold, wherein the method uses a core material made of a resin material having a stress of 0.3 MPa to 3.5 MPa at a 20% strain in a uniaxial compression test, as the core material,

• wherein the method uses a mold made of a thermoplastic resin having a Shore D hardness in a range of from 30 to 120 as the mold, and
• wherein after unloading of a pressure in the cold isostatic pressing, the core material is restored by protruding from the recess while the core material is placed in the position corresponding to the recess in the resin mold, and
• wherein the cold isostatic pressing is carried out while the core material, as a separate member from the mold, is placed at a position corresponding to the recess of the mold, with a wall of the mold sandwiched between the core material and the raw material powder.