CREEP BEHAVIOR OF TI-6AL-4V WITH MARTENSITIC AND EQUIAXED STRUCTURES AT 600°C

Ti-6Al-4V presents important properties as high specific strength, corrosion and creep resistance and metallurgical stability and it has been used in aerospace and aeronautical industries in some applications that requires high temperatures resistance. For these reasons is important understand Ti-6Al-4V deformation at high temperatures. A method of increasing the resistance of a material is heat treatments which can modify its microstructure. Aiming the improvement of Ti-6Al-4V creep resistance it was performed a specific heat treatment in this alloy to obtain a martensitic microstructure. The material was heat-treated at 1,050°C for 30 minutes and cooled in water until room temperature. The aim of this work is to evaluate Ti-6Al-4V creep behavior with equiaxed and martensitic microstructure at 600°C and stress conditions of 125 MPa, 250 MPa e 319 MPa at constant load. The alloy with martensitic structure showed higher creep resistance with a longer time in creep and lower steady-state creep rate