Hot Deformation Behavior of Ultra-Fine Grained Pure Ti

Abstract:

In the present study, compression tests were performed at a strain rate of 0.001 to 0.1 sˉ1 and in the range of 600°C to 900°C to investigate the high temperature deformation behavior and flow stress model 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. Flow accompanied by thermal softening was observed due to a combination of dynamic recovery and recrystallization for deformation at or above 600°C. Furthermore, microstructural evolutions of the as processed and hot deformed material were investigated. Based on constitutive equations, the flow stress was modeled for this light ultra-fine grained (UFG) material. The validity of the model was demonstrated with satisfactory agreement in light of the experimental mechanical behavior.

• Periodical: Advanced Materials Research (Volume 829)
• Pages: 10-14
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.829.10
• Online since: November 2013
• Authors: Seyed Vahid Sajadifar, Guney Guven Yapici*
• Keywords: Equal Channel Angular Extrusion/Pressing, Hot Deformation, Modeling, Severe Plastic Deformation, Titanium, Ultra-Fine Grained

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