High Pressure Torsion of Pure Ti: Effect of Pressure and Strain on Allotropy

Abstract:

High-pressure torsion (HPT) was conducted on commercial grade pure titanium (99.4%) by applying pressures in a wide range from 1.2 to 40 GPa. When the microhardness was plotted against equivalent strain, the hardness saturates to a constant level at each applied pressure. Such a level at the saturation depends on the applied pressure: for up to the pressure of 4 GPa, the saturation level is independent of the pressure but, for the pressures above 4 GPa, the hardness gradually increases with pressure because of the formation of an  phase. Bending tests showed that an excellent ductility as well as high bending strength was achieved for the sample processed at 2 GPa. The bending ductility was reduced for the sample at 6 GPa because of the  phase formation.

• Periodical: Advanced Materials Research (Volumes 89-91)
• Pages: 171-176
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.89-91.171
• Online since: January 2010
• Authors: Kaveh Edalati, Z. Horita, Masaki Tanaka, Kenji Higashida
• Keywords: High Pressure Torsion (HPT), Omega Phase, Severe Plastic Deformation (SPD), Titanium (Ti)

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