Compression deformation behaviours of ultrafine and coarse grained commercially pure titanium
Affiliation of Author(s):
冶金工程学院
Journal:
Materials Science and Technology
Key Words:
中文关键字:无,英文关键字:Ultrafine grained, Coarse grained, Commercially pu
Abstract:
Hot compression deformation behaviours of ultrafine grained (UFG) and coarse grained (CG)
commercially pure (CP)-Ti were investigated and compared by isothermal simulation tests.
Strains over 50% were achieved in these tests over a temperature range of 298–823 K and strain
rate of 1024–1022 s21. The results show that the peak stresses of UFG and CG CP-Ti fall with
increasing deformation temperature and decreasing strain rate. Within the plastic deformation
regime, the compressive stress–strain responses of UFG and CG CP-Ti exhibit quite different
features, which strongly depend on the temperature and strain rate. The flow stress of CG CP-Ti
monotonically increases with strain, while that of UFG CP-Ti increases first and then tends to be
constant after a peak value below recrystallisation temperature. The stress–strain curves of UFG
CP-Ti show similar characteristic with those of CG CP-Ti as the temperature is above
recrystallisation temperature. Strain rate sensitivity values m of the UFG CP-Ti increase with the
rise in temperature and are higher than those of CG CP-Ti. It can be concluded that deformation
of UFG CP-Ti is controlled by grain boundary and dislocation activity.
Note:
SCI:101LV/EI: 20131416171543