Finite Element Analysis of Phase Distribution in Forging of the Two-Phase Ti-6Al-4V Alloy to have a Hip Joint Implant

In this research, the finite element analysis (FEA) of the effect of forging parameters including temperature, strain rate and cooling rate on the percentage of α and β phases in forging of the two-phase Ti-6Al-4V alloy to fabricate a hip joint implant was investigated. In order to be used in FEA, the stress-strain curves of Ti-6Al-4V at temperatures ranged between 800 to 1000°C and, strain rates of 0.01, 0.1, 1 s^-1 up to a total strain of 0.45 by using hot compression test were obtained. The force-displacement curve of hot compression test of a cylindrical sample made of Ti-6Al-4V alloy from FEA and experiment in similar condition was used for verification. Results showed that all three input variables have an effect on the volume percentage of final α and β phases. By increasing the cooling rate, forging temperature and strain rate, the percentage of the final α phase decreases and the amount of the β phase increases. Additionally, in all cooling rates, the amount of the final α phase decreases from the center to the sides of samples.