Extruded material and method for producing the same

A method for producing an extruded material, comprising:

• extruding a metal material to obtain an extruded material;
• and
• performing correction of the extruded material,
• wherein
• the extruded material includes a peripheral wall having a closed loop-shaped cross-section and defining a hollow, and a middle rib connected to an inner peripheral surface of the peripheral wall and dividing the hollow,
• in an original shape of the extruded material before the correction, the middle rib has a cross-section curved with respect to an imaginary straight line connecting connecting portions connected with the peripheral wall, and
• the correction includes:
• disposing a mold so as to face an outer peripheral surface of the peripheral wall at a predetermined portion in a longitudinal direction of the extruded material;
• and
• expanding the peripheral wall outward at the predetermined portion, pressing the outer peripheral surface of the peripheral wall against an inner surface of the mold while reducing a degree of curvature of the middle rib with respect to the original shape, and transferring an inner surface shape of the mold to the outer surface of the peripheral wall.