Effect of environment on the creep behavior of the Ti-6Al-4V alloy

The influence of the atmosphere in tensile creep behavior of Ti-6Al-4V has been investigated in the temperature range from 500 to 700 °C and in the stress range from 14 to 520 MPa. Constant load creep tests were conducted in air and nitrogen atmospheres. Primary and secondary creep is being considered. The results show that both steady-state and primary creep follow power-law creep, with stress exponents in the range from 2.23 to 11.73. Analysis of the primary and secondary creep suggest that the creep mechanisms for both creep stages and atmospherics conditions are related to dislocation climb. The relation between primary creep time and steady-state creep rate, obeyed the equation tp(ε˙s)N=P for both atmospherics conditions at 500, 600 and 700 °C. The higher creep resistance of Ti-6Al-4V was observed in nitrogen atmosphere.