EFFECT OF HYDROGEN ON DISLOCATION VELOCITY-STRESS EXPONENTS OF Ti ALLOYS

The dislocation velocity-stress exponents,m~*,of commercial pure Ti,Ti-6Al-4V and Ti-15Mo alloys,which were charged with hydrogen,were measured by means of the stress relaxation method at room temperature.The results show that when hydrogen concentration in pure Ti,Ti-6Al-4V and Ti-15Mo alloys exceeds 310,620 and 1100 ppm respectively, the m~* value increases as the increasing of hydrogen concentration,that seems to be due to decreasing the binding energy of lattice.