BILLET FOR HIGH-STRENGTH FASTENERS MADE FROM DEFORMABLE TITANIUM ALLOY, AND METHOD OF MANUFACTURING THEREOF Russian patent published in 2020 - IPC C22F1/18 C22C14/00 

FIELD: metallurgy.

SUBSTANCE: present invention generally relates to metallurgy, particularly to materials of titanium alloy with given mechanical properties for making fasteners of aviation equipment. Billet for high-strength fasteners, made from deformed titanium alloy, containing wt. %: 5.5–6.5 Al; 3.0–4.5 V; 1.0–2.0 Mo; 0.3–1.5 Fe; 0.3–1.5 Cr; 0.05–0.5 Zr; 0.2–0.3 O; not more than 0.05 N, not more than 0.08 C, not more than 0.25 Si, titanium and inevitable impurities, in which the value of the structural aluminium equivalent [Al]eq = 7.5–9.5, and the value of the structural molybdenum equivalent [Mo]eq = 6.0–8.5, wherein equivalents are determined by following expressions: [Al]eq =  [Al] + [O] × 10 + [Zr] / 6; [Mo]eq = [Mo] + [V] / 1.5 + [Cr] × 1.25 + [Fe] × 2.5. Method of billet manufacturing for high-strength fasteners includes melting of ingot from titanium alloy with specified composition, manufacturing of forged billet from ingot at temperatures β- and/or (α + β)-area, forged billet machining, hot rolling at metal heating temperature in β- and/or (α + β)-area with production of rolled stock, subsequent annealing of rolled billet at temperature of 550–705 °C (1022–1300 °F) for at least 0.5 hour.

EFFECT: blanks are obtained in annealed condition with high tensile strength and double shear strength while maintaining high plastic properties.

12 cl, 6 tbl, 3 ex, 5 dwg