بررسي رفتار دما بالاي آلياژ بيومواد Ti-6Al-4V ELI با استفاده از رسم نقشه فرآيند

Hot Deformation Behavior of Medical Grade Titanium Alloy Ti-6A1-4V Using Processing Map

In this present work, high temperature behavior of titanium alloy (Ti-6A1-4V ELI) was investigated. Hot tensile test in range of 800 to 1050 °C and strain rates of 4.17xl04to 1 S1 were selected. Flow stress as a function of strain and temperature was applied in order to draw processing maps for this particular alloy. The map consists of a superplasticity region in a-(3 stability area. Maximum dissipation energy efficiency occurs near the temperature of 900 °C and the strain rate of 4.17xl04S1. The kinetics analysis using two models including ASHBY and SCHOCK showed a hot deformation of this alloy in this range of temperature and strain rate does not follow only one mechanism. Another result reveals that, at low strains rate, hot deformation of gram is mostly affected by the diffusion mechanism and at the higher strain rates, effect of stress is more observable. On the other hand, during the hot deformation of Ti-6A1-4V alloy thermal-stress mechanisms are active.