Hot deformation behavior of Ti–6.0Al–7.0Nb biomedical alloy by using processing map

Abstract

Abstract Ti–6.0Al–7.0Nb is a dual phase biomedical alloy used for artificial bone. Isothermal compression tests of Ti–6.0Al–7.0Nb biomedical alloy has been taken carried out on a Gleebe 3500 simulator at the strain rates of 0.001–1.0 s1 and temperatures of 750–900 °C. A constitutive equation represented as a function of temperature, strain rate and true strain was developed, and the hot deformation apparent activation energy is calculated about 341 kJ/mol. Processing maps were constructed on the basis of the experimental data for evaluation of the flow instability regime and optimization of processing parameters. Processing maps predict a single flow instability region occurred around the temperature range of 750–770 °C and the strain rate range of 0.03–1.0 s−1. The power dissipation maps at different strains exhibit similar features indicating that the processes involved in hot working have very short transient and are essentially of steady–state type. Ti–6.0Al–7.0Nb biomedical alloy can be deformed at the condition of (Topi: 850 °C, e opi : 1.0 s−1) with the peak η of 0.46 to obtain fine kinked and globular α phase for artificial bone.