METHOD FOR MANUFACTURING BIMETALLIC PIPES FROM TWO-PHASE (α+β)-TITANIUM AND WROUGHT ALUMINUM ALLOYS Russian patent published in 2023 - IPC B21C37/06 B21C23/22 B23K20/04 B23K20/22 C22F1/18 

FIELD: pipelines.

SUBSTANCE: invention relates to the field of metal forming and can be used for the manufacture of bimetallic pipes from (α+β)-titanium alloy and aluminum components firmly and tightly welded over their entire contact surface, designed to work under conditions of aggressive liquids or gases. (α+β)-titanium alloy is used to produce a round bar by two-cycle hot hydraulic forging, the temperature is not higher than 0.5 of the temperature of the polymorphic transformation of the alloy, the elongation ratio λ=8-10. After hydraulic forging, the bar is immediately quenched in water, then the bar is heated to a temperature not exceeding 0.5 of the temperature of the polymorphic transformation of the alloy and subjected to hot hydraulic forging in the opposite direction to the original one to obtain a round bar of the required diameter, elongation ratio λ=4-5. After hot hydraulic forging the bar is quenched into water, and then composite billet is assembled by piercing of the aluminum component heated to its hot deformation temperature, and the titanium component with simultaneous scalping of the titanium component and subsequent drilling of a through axial hole for the press needle. Next, the composite billet is subjected to hot hydraulic forging with an elongation factor λ>8 at a temperature that provides a ratio between the deformation resistances of the components at the level of 0.8-1.2.

EFFECT: obtaining bimetallic pipes with uniform welding strength of components along the length and perimeter of the pipes, without breaks in the aluminum component and high accuracy of geometric dimensions.

1 cl, 1 ex, 3 dwg