Thermomechanical behavior of Ti-6Al-4V alloy

Ti-6Al-4V, among the Ti alloys, is the most widely used. In the present work, the behavior of Ti-6Al-4V alloy has been investigated by the uniaxial hot isothermal compression tests and a series of dilatometric experiments were also carried out to determine the transformation temperatures at different cooling rates. Specimens for hot compression tests were homogenized at 1050degreesC for 10 min and then quickly cooled to different straining temperatures from 1050 to 850degreesC. Cooling rates were chosen fast enough to prevent high temperature transformation during cooling. Compression tests were conducted at temperatures from 1050 to 850degreesC in steps of 50degreesC at constant true strain rates of 10(-3) or 10(-2) s(-1). The apparent activation energy for compression in two-phase region was calculated 420 kJ(.)mol(-1). Partial globularization of alpha phase was observed in the specimen deformed at low strain rates and at temperatures near the transformation zone and annealed after deformation.