Materials modeling and finite element simulation of isothermal forging of electrolytic copper

Abstract

Isothermal forging of electrolytic copper is modeled using finite element simulation and materials models involving kinetic analysis and processing maps with a view to validate their predictions. Forging experiments were conducted on a rib–web (cup) shape in the temperature range of 300–800°C and at speeds of 0.01–10mms−1. The processing map for hot working of electrolytic copper revealed two domains in the temperature and strain ranges of (1) 400–600°C and 0.001–0.01s−1, (2) 650–950°C and 0.3–30s−1, where dislocation core diffusion and lattice self-diffusion are the rate-controlling mechanisms, respectively. Finite element simulation using the relevant experimental constitutive equations, predicted load–stroke curves that correlated well with the experimental data. The simulation has shown that there is a strain variation from about 0.4 to 4 in the web and rib regions of the forged component, although the dynamically recrystallized grain structure is fairly uniform, suggesting that dynamic recrystallization (DRX) is not sensitive to strain once the steady state flow is reached. The DRX grain size in the component is linearly dependent on Z and is similar to that predicted by the materials model after discounting for the longer time taken for the component removal.