Method for producing starting material for cutting

2:

• The method for producing the starting material for cutting as recited in claim 1,
• wherein, in the secondary forming, a processing rate of the primary molded article to the secondary molded article is set to be 2% to 5%.

3:

• The method for producing the starting material for cutting as recited in claim 1 or 2,
• wherein cold forging is used for the primary forming.

4:

• The method for producing the starting material for cutting as recited in claim 1,
• wherein hot forging is used for the primary forming.

5:

• The method for producing the starting material for cutting as recited in claim 1,
• wherein the secondary molded article includes a first part and a second part arranged in an axial direction and having different dimensions in a radial direction orthogonal to the axial direction, and
• wherein upset forging to compress in the axial direction is used as the secondary forming.

6:

• The method for producing the starting material for cutting as recited in claim 1,
• wherein a shape of the secondary molded article is shaped so as to be capable of forming a compressor impeller having a hub and a plurality of blades formed radially on an outer peripheral surface of the hub by cutting.

8:

• The method for producing the cut/machined product as recited in the claim 7,
• wherein a compressor impeller having a hub and a plurality of blades formed radially on the outer peripheral surface of the hub is obtained as a cut/machined product.

9:

• The method for producing the cut/machined product as recited in claim 8,
• wherein, in the compressor impeller, an amount of positional displacement of a central axis between a top face and a bottom face is set to 0.01 mm or less.

10:

• The method for producing the cut/machined product as recited in claim 8,
• wherein, in the compressor impeller, a ratio of the amount of positional displacement of a central axis between a top face and a bottom face with respect to a diameter of the bottom face is set to 0.013% or lower.

11:

• A starting material for cutting produced by the method for producing as recited in claim 1.