Workability characteristics and mechanical behavior modeling of severely deformed pure titanium at high temperatures

In the present study, compression tests were performed at temperatures of 600-900 degrees C and at strain rates of 0.001-0.1 s(-1) to study the deformation and workability characteristics of commercially pure titanium after severe plastic deformation (SPD). It was found that the effects of temperature and strain rate are significant in dictating the steady state flow stress levels and the strain values corresponding to peak flow stress. The strain rate sensitivity (m) during hot compression of severely deformed Ti was shown to be strongly temperature dependent, where m increased with the increase in deformation temperature up to 800 degrees C. High temperature workability was analyzed based on the flow localization parameter (FLP). According to the FLP values, deformation at and below 700 degrees C is prone to flow localization. The flow behavior was predicted using Arrhenius type and dislocation density based models. The validities of the models were demonstrated with reasonable agreement in comparison to the experimental stress-strain responses. (C) 2013 Elsevier Ltd. All rights reserved.