CP-타이타늄의 열간변형거동에 관한 연구

Abstract

Hot deformation behavior of CP(Commercially Pure)-Ti has been studied using Thermacmaster at various strain rates (0.001s^(-1)-10s^(-1)) and temperatures (750℃-950℃). Steady state flow behavior was established at strain rates of 0.1s^(-1) and below and flow curves tend to exhibit a small degree of flow softening at comparatively high temperatures. Dynamic material behavior during hot deformation has been studied using a model of Prasad et al. The result shows that a maximum material flow occurs under the condition of the strain rates 0.001s^(-1)-0.001s^(-1) at temperatures 750-800℃. Dynamic recrystallization is observed to be a primary dynamic process occurring at these conditions. A microstructural instability region has been also determined using Prasad et al.`s model and was generally in agreement with the result of experimental observation that such region is associated with the formation of shear bands. These results lead to a determination of an optimum condition for hot deformation of CP-Ti.