Patent ID: 11911816
Assignee: JFE STEEL CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC B  G | IPC B  G

Claim 2:
3. A method for identifying a variation factor portion of a springback amount, the method identifying a portion in a press formed part that is a factor for variation in a springback amount when variation occurs in the springback amount in the press formed part due to scattering in press forming conditions, and comprising:
press forming a first press formed part under first press forming conditions in advance;
creating a first press formed part model from three-dimensional shape measurement data obtained by measuring a surface shape of the first press formed part after die release;
performing mechanical analysis in a state in which the first press formed part model is sandwiched by a tool-of-press-forming model until reaching a press forming bottom dead center;
acquiring residual stress distribution in the first press formed part at the press forming bottom dead center under the first press forming conditions;
press forming a second press formed part under second press forming conditions different from the first press forming conditions within a range of the scattering in press forming conditions in advance;
creating a second press formed part model from three-dimensional shape measurement data obtained by measuring a surface shape of the second press formed part after die release;
performing mechanical analysis in a state in which the second press formed part model is sandwiched by the tool-of-press-forming model until reaching the press forming bottom dead center,
acquiring residual stress distribution in the second press formed part at the press forming bottom dead center under the second press forming conditions;
performing springback analysis on the first press formed part for which the acquired residual stress distribution in the first press formed part has been set, and calculating a first springback amount;
replacing a value of residual stress in a partial area of the acquired residual stress distribution in the first press formed part with a value of residual stress in an area corresponding to the partial area of the acquired residual stress distribution in the second press formed part;
performing springback analysis on the first press formed part for which the value of the residual stress has been replaced, and calculating a second springback amount;
obtaining a difference between the second springback amount and the first springback amount; and
identifying a portion in the first press formed part that is a factor for variation in springback amount of the first press formed part based on the obtained difference.