Press-formed product, and production method and production equipment line for producing the press-formed product

A production method for producing a press-formed product including a pair of flat sections and a bend section connecting the pair of flat sections, in which a bending radius of the bend section is R2 and an interior angle formed by the pair of flat sections is θ2, the production method comprising:

• a starting material preparation step of preparing a metal plate having a tensile strength of 590 MPa or more;
• a first forming step of subjecting the metal plate to press working using a die assembly to form an intermediate formed product having a bend section with a bending radius of R1 (mm) and an interior angle of θ1 (°) at a portion corresponding to the bend section of the press-formed product;
• and
• a second forming step of subjecting the intermediate formed product to press working using a die assembly to form the press-formed product having a bend section with a bending radius of R2 (mm) and an interior angle of θ2 (°) at a portion of the bend section of the intermediate formed product;
• wherein the bending radius R1 and the interior angle θ1 of the intermediate formed product and the bending radius R2 and the interior angle θ2 of the press-formed product satisfy conditions of Formulae (1) to (3) below:
• 1.05<A1/A2 (1)
• 1.0<R1/R2 (2)
• A1/A2<6.0/(R1/R2) (3);
• where, in the above Formulae, A1 (°) is a supplementary angle of the interior angle θ1 of the intermediate formed product, which is represented by Formula (A) below, and A2 (°) is a supplementary angle of the interior angle θ2 of the press-formed product, which is represented by Formula (B) below:
• A1=180−θ1 (A)
• A2=180−θ2 (B).

A production equipment line for producing a press-formed product including a pair of flat sections and a bend section connecting the pair of flat sections, in which a bending radius of the bend section is R2 and an interior angle formed by the pair of flat sections is θ2,

• the production equipment line comprising:
• a first press apparatus comprising a punch and a die for forming an intermediate formed product having a bend section with a bending radius of R1 (mm) and an interior angle of θ1 (°) at a portion corresponding to the bend section of the press-formed product, and
• a second press apparatus comprising a punch and a die for forming the press-formed product having a bend section with a bending radius of R2 (mm) and an interior angle of θ2 (°) at a portion of the bend section of the intermediate formed product;
• wherein the bending radius R1 and the interior angle θ1 of the intermediate formed product and the bending radius R2 and the interior angle θ2 of the press-formed product satisfy conditions of Formulae (1) to (3) below:
• 1.05<A1/A2 (1)
• 1.0<R1/R2 (2)
• A1/A2<6.0/(R1/R2) (3);
• where, in the above Formulae, A1 (°) is a supplementary angle of the interior angle θ1 of the intermediate formed product, which is represented by Formula (A) below, and A2 (°) is a supplementary angle of the interior angle θ2 of the press-formed product, which is represented by Formula (B) below:
• A1=180−θ1 (A)
• A2=180−θ2 (B).