High Temperature Tensile Strength of TI6AL4V Processed by L-PBF—Influence of Microstructure and Heat Treatment

Ti6Al4V is the most widely used α-β Titanium alloy for application in medicine, automotive, and aerospace, known for its high strength and corrosion resistance, but also its high maximal operating temperature of around 420°C. Combined with its decent weldability under a shield atmosphere it became a standard alloy for additive manufacturing processes, especially laser and electron beam powder bed fusion (L-PBF). Although this material is being well studied, the influence of the L-PBF process on its tensile properties at elevated temperatures remains almost unexplored. For that reason, this work focuses on the analysis of the tensile properties of Ti6Al4V up to 500°C for different heat treatments and compares it to aerospace standards. Furnace annealed samples reach a tensile strength between 1022 to 660 MPa from room temperature to 500°C respectively while stress-relieved specimens reach 1205 to 756 MPa. Stress-relieved samples show a lower ductility at room temperature but elongation at break increases at high temperature and outperforms furnace annealed samples at 500°C.