Deformation behaviour and new constitutive equation utilising the grain size of commercial TC6 titanium alloy

Isothermal compression tests on a commercial TC6 titanium alloy have been conducted at deformation temperatures of about 800-1040°C, strain rates of 0.001-50 s^-1 and height reductions of 30-50%. The microstructural evolution is represented through the measured grain size of the prior α-phase. Meanwhile, a new constitutive equation, which includes the grain size, is established for high temperature deformation behaviour. The procedure required to formulate a constitutive equation from the experimental results is presented. The constitutive equation to model the behaviour of the TC6 titanium alloy during high temperature deformation is validated and its formulation is presented. The results show that the present equation is satisfactory for describing the behaviour of the TC6 titanium alloy during high temperature deformation. The maximum difference between the calculated and the experimental results is less than 15%.