Processing process of difficult-to-deform high temperature alloy GH141 cold-drawn material

Abstract

The invention discloses a processing process of a difficult-to-deform high temperature alloy GH141 cold-drawn material. On one hand, the structure of a cold-drawing blank and the ratio of cold drawing decrease section are controlled and the internal stress of a rod obtained after cold drawing is reduced by use of a special process; on the other hand, excellent usability is obtained by use of a reasonable thermal treatment process. The adopted technical scheme is as follows: 1, the internal structure of the cold-drawing blank is controlled; 2, softening annealing treatment is adopted; 3, a reasonable ratio of cold drawing decrease section is selected; 4, two different straightening processes are adopted after cold drawing; 5, a reasonable thermal treatment process is selected. The processing process of the difficult-to-deform high temperature alloy GH141 cold-drawn material has the advantages that the structure of the blank is controlled to be uniform, the grain is fine and the crack formation trend can be effectively reduced, the hardness of the cold-drawing blank is reduced by virtue of softening annealing, the internal stress of the rod obtained after cold drawing is reduced effectively by virtue of straightening, and due to the adopted reasonable heat treatment process, at a room temperature, the plastic percentage elongation after fracture of the cold-drawn rod is 25% and the percentage reduction of area is 22%, at 760 DEG C, the high temperature tensile plastic percentage elongation after fracture of the cold-drawn rod is 34% and the percentage reduction of area is 36%; in short, the difficult-to-deform high temperature alloy GH141 cold-drawn material is excellent in properties.

Description

technical field [0001] The invention belongs to the field of cold-drawn processing of metal materials, and discloses a process for processing hard-to-deform high-temperature alloy cold-drawn materials, which is mainly used for the production of GH141 alloy cold-drawn materials for fasteners. Background technique [0002] Difficult-to-deform superalloy cold-drawn materials are mostly used in key components of aerospace engines because of their excellent performance such as high temperature resistance, high strength, corrosion resistance, and oxidation resistance. Due to the high strength of this type of alloy, the internal stress increases sharply during cold working, and crack defects are prone to occur, especially the bar has high performance indicators, strict organizational requirements, and low yield. [0003] GH141 alloy is a precipitation hardening nickel-based superalloy developed on the basis of the American Rene′41 alloy composition and process, after optimizing and...

AI Technical Summary

Problems solved by technology

[0004] GH141 alloy is a typical variety of hard-to-deform high-temperature alloy. Since the alloy contains a large amount of solid solution strengthening elements C, Mo, Cr, Co, etc., and contains more Al, Ti aging strengthening elements, the content of Al, Ti elements in the alloy and It reaches more than 4.7%, and its γ' phase Ni3 (Al, Ti) content reaches about 24%, which makes the alloy have poor processing plasticity and a narrow deformation temperature range. It is a very difficult to deform alloy, especially for cold deformation processing. If the bar is placed for a long time, it will easily cause stress cracks in the bar itself. At the same time, in the process of annealing and heat treatment, when it reaches 750 ° C ~ 910 ° C, a large amount of strengthening phase γ' phase will be precipitated, resulting in a larger structure. The superposition of the two stresses can easily cause transverse and longitudinal cracks on the surface of the bar, resulting in a large number of cold-drawn bars being rejected

In order to avoid stress cracks in the bar during production, softening and annealing treatment is required quickly after the bar is drawn, which seriously affects the production efficiency, and there are still surface cracks during the softening and annealing process, so the yield of the cold drawn material is extremely low, only in About 20% to 30%, at the same time, due to the need for multiple softening and annealing, the energy consumption is high and the production efficiency is low

Moreover, in the standards for cold-drawn rods, the requirements for room temperature tensile and 760°C high-temperature tensile plasticity are both elongation after fracture ≥ 8%, and reduction of area ≥ 10%, which is difficult to meet.

Difficult-to-deform superalloys are usually used as important materials for military industry. Their production technology is strictly kept secret abroad, and relevant information cannot be found.

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