Control of the structure of titanium alloys by the method of thermohydrogen treatment

We show the possibility of controlling the structure of titanium alloys of different classes by means of their thermohydrogen treatment and consider the process of structure formation in shaped castings of VT20L alloy under additional alloying with hydrogen. Depending on the hydrogen content in the course of thermohydrogen treatment, the transformation of a course-lamellar structure into a fine-lamellar one with alpha-particle sizes from several micrometers to nanometers is possible. We describe the mechanism of phase and structural transformations in titanium alloys with a heightened content of beta-eutectoid stabilizers (Ti-12Cr) or aluminum (VT6, VT23) under the action of hydrogen. We also show the possibility of producing a composite structure of the beta-phase and TiCr(2) intermetallic compound or noncoherent particles of the alpha(2)-and alpha-phases, depleted with aluminum.