Thermal cycling behavior of as-quenched and aged Ti-6Al-4V alloy

Thermal cycling tests between 77 and 623 K were performed on Ti-6A1-4V alloy; the tensile properties were evaluated, and transmission electron microscopy (TEM) microstructural analysis was performed both before and after thermal cycling. Thermal cycling (1000 cycles) promptly increases the strength of the as-quenched alloy, induces a slight decrease in strength for the near-peak-aged alloy, and makes no change for that of,the overaged alloy. The elongation of the alloy in all heat-treated conditions decreases after 1000 thermal cycles. The loss of fracture elongation of the as-quenched alloy is the largest, but the residual ductility is the highest. The loss of fracture elongation for the near-peak-aged alloy is lower, and the residual plasticity is higher than those for the overaged alloy.