Journal of Materials Science, Vol.47, No.8, 3837-3848, 2012
Optimizing the hot-forging process parameters for connecting rods made of PM titanium alloy
In order to optimize the processing parameters of a new low-cost titanium alloy connecting rod made of powder forging, the deformation behavior of an alpha + beta type Ti-1.5Fe-2.25Mo (wt%) alloy produced by elemental powder metallurgy (PM) route was studied using isothermal compression tests. The constitutive equations and a processing map were established to characterize the flow behavior and predict the optimum deformation parameters. The calculated apparent activation energy was 257.73 kJ/mol for deformation in the alpha + beta phase region and 378.01 kJ/mol in the beta phase region. Two deformation mechanism domains were found: alpha + beta -> beta phase transformation and dynamic recrystallization. The results show that the optimum deformation parameters for the present alloy are (700-800 A degrees C, 10(-1.7)-1 s(-1)) and (800-900 A degrees C, 10(-2)-10 s(-1)). Based on these results, a finite element method (FEM) simulation of the hot-forming of a connecting rod was conducted, and the simulated results have been successfully used in an industrial forging of the connecting rod.