We proposed a method for the treatment of VT9 alloy, which increases its conventional yield strength by 25percent and ultimate strength by 15percent at 400-550 deg as compared with the traditional strengthening treatment. This method consists of the saturation of blanks with hydrogen, and their deformation, quenching, aging, and dehydrogenating vacuum annealing. Since the growth of strength characteristics is connected with the formation of a special structural state in the alloy, we describe the results of its investigation after each stage of treatment. In this alloy, one can obtain a fine-grained lamellar microstructure with a size of P-grains of 20 to 40mum and the alpha-phase, whose composition is close to ordered Ti_3Al intermetallic compound. The structural state and properties of the alloy remain invariable after its additional holding at 500 deg for 100 h.
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