Method for rolling and forming TC11 titanium alloy thin-walled rings

Abstract

The invention discloses a method for rolling and forming TC11 titanium alloy thin-walled rings, which is used for rolling and forming thin-walled rings with high size precision and good organization and performance. The method comprises the following steps: firstly, nesting a pre-rolled titanium alloy billet which is heated to a deformation temperature and a preheated follow-up die sleeve into a ring rolling mill, and positioning the two workpieces by a main roller, a core roller, a holding roller, an upper cone roller and a lower cone roller of the ring rolling mill, wherein the follow-up die sleeve is nested in the pre-rolled billet; and then, starting up the ring rolling mill to enable the core roller to make a feed motion radially towards the direction of the main roller and roll the pre-rolled billet together with the main roller by the rolling force of 200KN-4000KN under the support of the follow-up die sleeve, so that the width of the pre-rolled billet is expanded radially at a speed of 5-10mm / s, the wall thickness of the pre-rolled billet is gradually reduced, and after the deformation of the pre-rolled billet reaches 25%-45%, the pre-rolled billet is rolled into a thin-walled ring. The minimum value of the wall thickness of the titanium alloy thin-walled ring rolled by the method is 25 mm, and the maximum value of the height-to-thickness ratio thereof is 25 mm. The ring is mainly used for components of revolved bodies such as cylindrical shells and the like used in the fields of aviation and the like.

Description

technical field [0001] The invention relates to a rolling forming method of a ring forging, in particular to a rolling forming method of a TC11 titanium alloy thin-walled ring. Background technique [0002] TC11 titanium alloy is a two-phase titanium alloy with good comprehensive performance. The cylindrical shells and other rotary parts used in aerospace and other fields, such as thin-walled rings such as aero-engine drums, are required to be at 500 It has excellent heat strength performance and high room temperature strength when working for a long time below ℃. During rolling, due to the narrow deformation temperature range of the alloy, the small deformation, the thin wall thickness of the forging, and the high requirements for dimensional accuracy, performance and structure, the difficulty of rolling and forming is increased. [0003] The Chinese invention patent specification CN 101279345A published on October 8, 2008 discloses a rolling forming method of titanium all...

AI Technical Summary

Problems solved by technology

When using this method to roll thin-walled TC11 titanium alloy thin-walled rings, since the rolling die is fixed on the roll (that is, the main roll and the core roll), the gap between the pass shape of the rolling die and the pre-rolled billet during rolling The intense friction between them not only makes the rolling process very unstable and affects the production, but also easily leads to the temperature rise of the pre-rolled slab, which affects the structure and properties of the alloy, such as defects such as structure variation and coarse grains.

[0004] When using the above method and directly using the main roll and core roll of the ring rolling machine to roll (such as the rolling ring billet in the above method) thin-walled TC11 titanium alloy thin-walled rings, due to the rigidity of the core roll and other parts of the ring rolling machine Influenced by the thin-walled ring, coupled with poor structural rigidity and small machining allowance, it is easy to cause plastic instability of the pre-rolled billet during the rolling process, resulting in flattening, bell mouth, etc., resulting in the shape and size of the ring not reaching It is scrapped until the design use or machining requirements, which is a big loss for the expensive TC11 titanium alloy material

[0005] During the rolling process, when the pre-rolled slab is first rolled, the rolls are shifted to one side of its rotation direction, and then to the other side, so that the pre-rolled slab has a tendency to move toward its other side during the rolling process. The holding rollers on both sides swing left and right, affected by the reaction force generated by the holding rollers, the rings are easily crushed and scrapped

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