Effect of process parameters on microstructural variables of a commercial TC6 titanium alloy disc

The interaction between the deformation behaviour and the microstructure evolution is the main characteristic in the forging process of titanium alloy and this interaction is researched using finite element (FE) simulation. Coupled simulation of deformation behaviour with microstructure evolution has been carried out by means of a new constitutive equation presented by Li et al. (Mater. Sci. Technol., 2004, 20, 1256-1260). The effect of deformation temperature, hammer velocity, height reduction and shear factor on the microstructure variables, including grain size and volume fraction, has been studied in the forging process of the TC6 titanium alloy disc with deformation temperatures of 880-940°C, hammer velocities of 1·2-12 000 mm min^-1 and shear factor (m) of the friction of 0·1-0·4. The simulated results show that deformation temperature, hammer velocity and height reduction have a significant effect on the microstructure evolution and this effect is more significant on the microstructure evolution in hot forging than that in isothermal forging. The simulated results are in good agreement with the experimental results.