Finite element modeling of the formation of adiabatic shear bands in AISI 4340 steel

Adiabatic shear bands (ASB) occur during the plastic deformation of metals at high strain rates in torsional split-Hopkinson bar tests. The formation of ASB in AISI 4340 steel was modeled using the finite element (FE) method. Both strain hardening and thermal softening were considered and attention was given to the initialization and growth of the ASB. The calculated results indicate that the ASB could initialize at material defects. The evolution of the ASB occurs in three stages and is significantly influenced by strain hardening and thermal softening. Also, thermal conduction plays an important role during the formation of the ASB.