Thermomechanical Behavior of Commercially Pure Titanium (CP-Ti) During Isothermal Compressive Deformation

摘要

The thermomechanical deformation behavior of commercially pure Titanium (CP-Ti) was studied by isothermal compression up to 50% height reduction of specimen at 773-1273 K with strain rate 0.01-1.0 s~(-1) with boron nitride as solid lubricant. The influence of Zener-Hollomon parameters, strain, strain rate imposing on the flow stress were analyzed in the high-temperature deformation of CP-Ti in the α + β phase region. The apparent activation energy of deformation calculated to be 343.69 kJ mol~(-1) and the processing map shows that the dynamic softening is accelerated with increase of deformation temperature and decrease of strain rate, and can be divided into three different regions viz., three-stage work hardening, two-stage work hardening, and flow softening. Geometric dynamic recrystallizations were found as a result of strain rate and temperature while describing the grain refinement process of CP-Ti during high-temperature compression.