Abstract: A manufacturing method for a diffuser includes a first process in which a cylindrical solid material with a fiber flow extending in an axial direction is forged to form a first shaped component which has disk-shaped top and bottom surfaces; a second process in which the first shaped component is rotated degrees and forged in a direction perpendicular to the axial direction to form a second shaped component which has a flange and a cylindrical portion; and a third process in which the second shaped component is press-formed in a direction perpendicular to the fiber flow to form a third shaped component which has a flange including a central hole portion and an outer edge engaging portion with a fiber flow extending in a radial direction, and a bottomed cylindrical portion including a communicating hole.

Abstract: A manufacturing method for a diffuser comprises a first process of forming a first molded component, by gradually forging a cylindrical solid material having fiber flow extending in an axial direction from an axial direction thereof, the first molded component including a flange section having a central hole section, and a bottomed cylindrical section having a communication hole leading to one end, in the axial direction, of the flange, and communicating with the hole section, and having fiber flow that is flowing substantially in the axial direction without being cut, and a second process of forming a second molded component, by split molding a peripheral groove using split dies at the outer periphery of the bottomed cylindrical section of the first molded component, including a flange having a central hole section, and a bottomed cylindrical section having a communication hole leading to one end, in the axial direction, of the flange, and communicating with the hole section, and having the peripheral groove