Workability characteristics and mechanical behavior modeling of severely deformed pure titanium at high temperatures: Fid-Bau Portal

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

Sajadifar, Seyed Vahid / Yapici, Guney Guven

Highlights • UFG Ti was processed by severe plastic deformation using equal channel angular extrusion. • The processed UFG material was compression tested at high temperatures up to 900°C. • Evolution of material properties for UFG Ti is shown with respect to temperature and strain rate. • Flow stress behavior was predicted by Arrhenius formulation and dislocation density modeling.

Abstract In the present study, compression tests were performed at temperatures of 600–900°C and at strain rates of 0.001–0.1s⁻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°C. High temperature workability was analyzed based on the flow localization parameter (FLP). According to the FLP values, deformation at and below 700°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.