METHOD OF THERMOMECHANICAL TREATMENT OF SHEETS OF TWO-PHASE TITANIUM ALLOYS TO PRODUCE LOW VALUES OF THERMAL COEFFICIENT OF LINEAR EXPANSION (TCLP) IN PLANE OF SHEET Russian patent published in 2017 - IPC C22F1/18 B21B3/00 

FIELD: metallurgy.

SUBSTANCE: method for thermomechanical treatment of sheet semi-finished products made of two-phase titanium alloy with molybdenum equivalent from 3.3 to 22% includes hot rolling of semi-finished sheet products and cold longitudinal-transverse rolling. Hot rolling is carried out at temperature from 500°C to T_pt - 20°C with total reduction of not less than 10%, then hardening is carried out from temperature in the range from 600°C to T_pt, and subsequent cold longitudinal-transverse rolling of semi-finished sheet product is carried out at temperature not higher than 300°C with total reduction from 1 to 30%, where T_pt is temperature of complete polymorphic transformation of used alloy melt. The TCLP value is not more than 5⋅10⁶ K^-1 in sheet plane in the temperature range from -140 to +80°C, while strength is greater than 900 MPa and ductility more than 5%.

EFFECT: producing low values of thermal coefficient of linear expansion in the sheet plane.

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