Evaluation of heat treatment in creep of Ti-6Al-4V alloy

This study aimed to evaluate the resistance of a Ti-6Al-4V alloy in creep after heat treatments. It was used a Ti-6Al-4V alloy in cylindrical bars forms, forged condition and annealing at 190 °C for 6 hours and cooled in air. The microstructure Ti-6Al-4V alloy was evaluated after heat treatment and was submitted to creep tests at 600 °C and stress conditions from 125 to 319 MPa at constant load. Samples preparation for optical microscopy and scanning electron microscopy followed the usual methods of metallography. Three different conditions of heat treatments were utilized to obtain the following microstructures: Widmanstätten, Martensite and Bimodal. The alloy with Widmanstätten structure shows greater resistance to creep with a longer life time in creep.