PROPERTIES OF AN ADIABATIC SHEAR-BAND PROCESS ZONE

THE FORMATION of adiabatic shear bands is examined with an approximate analytic model. The shear band is viewed as a propagating feature with a well-defined front. The shear band is further partitioned into a shear-band process zone within which most of the adiabatic heating and shear stress relaxation occurs, followed by a quasi-steady zone within which little dissipation occurs. Although a one-dimensional analysis of the shear-band dynamics is initially pursued, the analysis is then used to calculate properties of the inherently two-dimensional shear-band process zone. The length and width of the process zone are calculated along with the shear displacement. The model is further used to calculate the energy dissipation within the shear-band process zone and the concept of a shear-band toughness is introduced. The flow field within the vicinity of the process zone is also examined. Calculated properties of the shear-band process zone compared well with available experimental data.