Roll forming method of GH4033 high-temperature alloy thin-wall ring piece

Abstract

The invention discloses a roll forming method of a GH4033 high-temperature alloy thin-wall ring piece, wherein the thin-wall ring piece is roll-formed and has high size precision and excellent structure and performance. The technical is as follows: sleeving a titanium alloy pre-rolled blank which is heated to a deforming temperature and a pre-heated follow-up mould sleeve into a ring rolling mill; sleeving the follow-up mould sleeve in the pre-rolled blank; positioning the two workpieces by utilizing a main roller, a core roller, holding rollers and upper and lower conical rollers of the ring rolling mill; and starting the ring rolling mill, wherein the core roller of the ring rolling mill performs radial feed motion toward the main roller and rolls the pre-rolled blank together with the main roller under the support of the follow-up mould sleeve with a rolling force of 220-4,200 KN so that the pre-rolled blank is widened radially at a speed of 5-8 mm / s and the wall thickness is gradually reduced; and after the deformation of the pre-rolled blank reaches 25-45%, the pre-rolled blank is rolled into a thin-wall ring piece. The minimum of the wall thickness of the titanium alloy thin-wall ring piece roll-formed by the method is 25 mm, and the maximum of the height-thickness ratio is 25 mm; and the ring piece is mainly applied to the rotational parts such as a cylindrical shell and the like used in the fields of aerospace 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 GH4033 superalloy thin-walled ring. Background technique [0002] The GH4033 superalloy is a nickel-based deformed superalloy based on nickel-chromium, which is used in the aerospace and other fields of aerospace and other fields, such as cylindrical shells and other rotary parts, such as thin-walled rings such as the front case of aero-engines. , It is required to have sufficient high temperature strength for long-term use at 700-750 °C, and good oxidation resistance for long-term work below 900 °C. 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 101279346A publi...

AI Technical Summary

Problems solved by technology

When using this method to roll thin-walled GH4033 superalloy thin-walled rings with thin wall thickness, since the rolling die is fixed on the roll (that is, on 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 GH4033 superalloy thin-walled rings, due to the rigidity of the core roll and other components of the rolling ring 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 will be scrapped until the design use or machining requirements, which is a big loss for the expensive GH4033 superalloy 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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