Compressor housing for turbocharger and method for manufacturing the same

A compressor housing for a turbocharger configured to house a compressor impeller, the compressor housing comprising:

• an intake port configured to suck in air toward the compressor impeller;
• a shroud part having a shroud surface that surrounds the compressor impeller in a circumferential direction;
• a diffuser part that is formed on an outer circumferential side of the compressor impeller in the circumferential direction and is configured to pressurize air discharged from the compressor impeller;
• and
• a scroll chamber configured to guide compressed air having passed through the diffuser part to outside;
• wherein
• the compressor housing is dividably composed of a plurality of pieces including a scroll piece having at least the intake port and a portion of the scroll chamber, and a shroud piece having at least a portion of the scroll chamber, a portion of the diffuser part, and the shroud part,
• the scroll piece and the shroud piece are assembled to each other by press-fitting a press-fitting portion of the shroud piece into a press-fitted portion of the scroll piece in an axial direction, and
• the scroll piece and the shroud piece are sealed to each other by annularly forming a plastic flow portion that is formed by plastic flow caused to a pressure-contacting portion and a pressure-contacted portion by pressure-contacting the pressure-contacting portion that is provided on either one of the scroll piece and the shroud piece with the pressure-contacted portion that is provided on the other one of the scroll piece and the shroud piece in the axial direction.