Constitutive Relation and Secondary Recrystallization Maps of the TC18 Titanium Alloy During Hot Deformation

The constitutive equation and the secondary recrystallization maps, which reflect the flow stress characteristics and microstructure-deformation relationship of the material, respectively, are the key data for the TC18 titanium alloy during the hot deformation. In the present paper, the hot compression deformation was carried on Gleeble-3800 under the conditions that the deformation temperatures were 790 similar to 900 degrees C, the strain rates 0.01 similar to 10 s(-1) and the strains 0.1 similar to 0.5. By fitting the 6(th) polynomials of epsilon and alpha, n, Q, InA in the Arrhenius formula, TC18 titanium alloy's constitutive equation of hot compression was established. The predicted values of flow stress of the hot compression are in good agreement with the measured values; the secondary recrystallization maps of each strain rate were drawn by observing the microstructure and measuring a grains' sizes.