Hot deformation behavior and microstructure evolution of sintered TC4 alloy using hydrogenated powder

The hot deformation behavior and microstructure evolution of TC4 alloy by die forming and sintering using hydrogenated powder with hydrogen content of 0.42% were studied in the temperature range 850~1000 degree C and strain rate range 0.001~0.1 s(-1) by hot compression tests. Characteristics of stress strain curves of the alloy deformed with the test parameters were analyzed. Kinetics analyses indicate that the stress exponent and deforming activation energy were 3.97 and 507.35 kJ upsilon . mol(-1) respectively, which indicate that dynamic recrystallization occurred. Microstructure observation indicates that the beta grains was elongated along metal flowed with deformation in beta region, the same microstructure change of beta phase as beta region besides recrystallization aggravated in alpha + beta region deformation, it take place recrystallization of alpha phase original duplex structure which the mass fraction of primary alpha phase content showed a decreasing trend.