METHOD OF FORGING WORKPIECES WITH ULTRA-FINE-GRAINED STRUCTURE OF TWO-PHASE TITANIUM ALLOYS Russian patent published in 2019 - IPC B21J5/00 B21J1/00 C22F1/18 

FIELD: technological processes.

SUBSTANCE: invention relates to metal forming and can be used for production of billet from titanium two-phase alloys. Billet is subjected to thermal treatment to produce duplex structure with volume fraction of grains of primary α-phases of not more than 30 %. Then, workpiece is plastically deformed by high-speed rotary forging at temperature of 200…300 °C is lower than temperature of polymorphous transformation, with logarithmic degree of deformation of not less than 1.5. UFG structure of a bimodal type is obtained. Further, workpiece is forged in isothermal conditions. For this purpose, die and workpiece are heated to temperature of 200…300 °C is lower than temperature of polymorphous transformation of workpiece material. After forming, workpiece is cooled to room temperature and stabilizing annealing is performed at temperature of 400…450 °C is lower than temperature of polymorphous transformation, for 2…6 hours with cooling in air.

EFFECT: result is improved mechanical properties of the workpiece.

1 cl, 1 ex