BETA-TITANIUM ALLOY AND METHOD OF ITS THERMOMECHANICAL TREATMENT

摘要

FIELD: metallurgy.;SUBSTANCE: beta-titanium alloy with ultrafine-grained structure consists of beta-phase gains with mean size not exceeding 0.5 mcm, precipitations of secondary alpha-phase particles of spherical shape and mean size not exceeding 0.5 mcm and volume fraction in the structure making at least 40%. Proposed method comprises intensive plastic deformation and thermal treatment. Thermal treatment is carried out before deformation by heating to temperature exceeding that of polymorphic conversion by 5-15°C for, at least, one minute for 1 mm of diameter cross-section and quenching in water. Intensive plastic deformation is performed by equal-channel angular pressing with changing deformation direction through 90 degrees after every deformation cycle at (T_"пп"-200…T_"пп"-150)°C with total accumulated deformation e≥3.5 and subsequent quenching in water.;EFFECT: higher strength and fatigue characteristics of alloys.;2 cl, 1 tbl, 1 ex