This flange bolt is cold formed from round steel wire using a four-blow progression on a high speed cold header. This process was optimized using DEFORM-3D. An earlier version of the design experienced issues with ductile fracture from time to time, before DEFORM was available.
The original process was simulated. DEFORM provided grain flow, plastic strain and damage models to the User, which correlated well with the known quality problems. Redesigns were simulated, with an objective of reducing the Damage value. In this case, a normalized Cockroft-Latham model was used; along with plastic strain and grain flow.
The simulated models cost less than shop trials, as no tooling is required. In cases with occasional failures, the field variables can be used to assess the probability of an improvement for a given design. DEFORM simulations of this type of process can be run faster than shop trials requiring new tooling (one day vs. days or weeks). More importantly, DEFORM provides more information than any shop trial.