Method for manufacturing vehicle suspension arm and vehicle suspension arm

A method for manufacturing a vehicle suspension arm including a hollow body portion, and coupling portions facing each other in a state where axes of a pair of through-holes are aligned with each other, the method comprising:

• forming at least the pair of through-holes including cylindrical flanges raised from a plate surface, in a workpiece by burring;
• and
• applying stepwise bending to the workpiece after the forming,
• the body portion having two side walls facing each other, and a base portion connecting the two side walls to each other and extending along one direction, and the coupling portions extending along the one direction from end portions in the one direction of the two side walls and facing each other apart from each other,
• wherein the stepwise bending comprises
• a first bending step of performing preliminary bending while holding a portion that composes the base portion of the body portion and a portion that composes the coupling portions in the workpiece by a first punch, and
• a second bending step of, while releasing holding of the portion that composes the coupling portions by the first punch, subsequently to the first bending step, performing bending along a fold given by the first bending step while holding the portion that composes the base portion of the body portion by a second punch, and
• wherein the portion that composes the coupling portions includes the plate surface around the flanges, and
• the preliminary bending in the first bending step is performed while holding the plate surface around the flanges by the first punch.