Method for forming high-temperature alloy split casing ring piece with low notch deformation
By regulating the die forging of special-shaped blanks and the cooling rate of heat treatment, combined with thermal insulation coating and slow-feed wire cutting, the problem of large deformation of the casing ring cut was solved, and an efficient and low-cost preparation method was achieved.
Patent Information
- Application Number
- CN202510985711.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-09-16
AI Technical Summary
In the process of preparing aircraft engine casing rings, the deformation of the cut is large, resulting in the inability to fine-process, low material utilization, long process flow and high cost.
By using die forging special-shaped blanks, adjusting the heat treatment cooling rate and using thermal insulation coatings to control the residual stress distribution, combined with slow wire cutting technology, the amount of incision deformation can be reduced.
It improves material utilization, reduces machining workload, shortens process flow, reduces forging costs, and improves production efficiency.
Smart Images
Figure CN120644929A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of forging, and in particular relates to a method for forming a high-temperature alloy split casing ring with low notch deformation. Background Art
[0002] The casing is the primary load-bearing component of an aircraft engine, with a complex external structure. During operation, it primarily bears gas loads and mass inertia forces, as well as thermal and acoustic loads, and some assembly stresses. Therefore, it requires sufficient creep resistance, strength, stiffness, and stability. As the most complex of the annular casings, the split casing undergoes a manufacturing process involving upsetting, punching, ring rolling, bulging, heat treatment, rough machining, slitting, and fine machining. Each of these manufacturing processes generates residual stresses within the material, which are transferred and accumulated at each step. However, due to the thin wall thickness and poor rigidity of the casing rings, coupled with irrational residual stress distribution, the residual stresses can easily cause deformation during slicing of the entire ring. This can lead to problems such as widening or shrinking of the cut and non-conforming metal flow lines, making fine machining impossible and resulting in scrap. Summary of the Invention
[0003] The present invention provides a method for forming a high-temperature alloy split casing ring with low cut deformation. The method improves deformation uniformity by designing a special-shaped blank, and regulates the residual stress distribution on the inner and outer ring surfaces of the blank by adjusting the heat treatment cooling rate. The cut deformation is small during cutting; the material utilization rate is improved, the process flow is short, the forging cost is low, and the production efficiency is high.
[0004] The technical solutions of the present invention are as follows: A method for forming a high-temperature alloy split casing ring with low notch deformation comprises the following steps: 1) The forging of the split receiver ring is formed by ring rolling of die forged special-shaped billets. The difference in deformation of different parts of the forging is ≤5%. The die forging heating temperature is 955~995℃; 2) During die forging and ring rolling, the die temperature in contact with the inner ring surface of the blank is 400~500℃; 3) During the bulging process, the billet heating temperature is set to 940~990℃, and the bulging deformation is set to 1~4%; 4) During heat treatment cooling, apply thermal insulation coating on the outer ring surface of the blank or place a high-temperature workpiece; 5) When cutting the split receiver ring, use slow wire cutting and control the cutting rate to 1~5cm / min.
[0005] Furthermore, in the method for forming a high-temperature alloy split casing ring with low notch deformation, in step 4), the thickness of the thermal insulation coating is 1-2 mm.
[0006] The beneficial effects of the present invention are as follows: the present invention improves deformation uniformity by designing special-shaped blanks, and regulates the residual stress distribution on the inner and outer ring surfaces of the blank by adjusting the heat treatment cooling rate, which will greatly improve the consistency of forging microstructure and performance, the uniformity of residual stress distribution, the residual stress levels of the inner and outer ring surfaces are basically consistent, the streamlines are distributed in a shape-following manner, and the residual stress of the forging is regulated to a low level and uniformly distributed state, and the deformation of the incision is small during cutting; the material utilization rate is improved, the machining amount is reduced, the process flow is short, the forging cost is low, and the production efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 This is a schematic diagram of the die forging process of a high-temperature alloy split casing; Figure 2 is a residual stress distribution diagram of a part in the embodiment; Figure 3 This is the residual stress distribution diagram of the parts in the original preparation process. DETAILED DESCRIPTION
[0008] like Figure 1 As shown, a method for forming a high-temperature alloy split casing ring with low notch deformation includes the following steps: 1) Cutting the GH4706 bar on a sawing machine to obtain an initial blank 1; spraying a lubricant on the initial blank 1 and heating it at a heating temperature of 1060° C.; 2) Upsetting and punching: Install a die on a forging press and perform upsetting and punching on the initial blank 1. A smooth curved surface with a large curvature is provided in the punching die cavity to reduce tensile stress and shear force generated during forming and avoid the generation of cracks. The transfer time is ≤ 60 s, the die temperature is preheated to 300°C, and the punch temperature is 400°C. The hammer head pressing speed is 30 mm / s, and the deformation is 55%. A blank 2 with a hole is obtained. 3) Pre-rolling: Spray lubricant on the perforated blank 2 and heat it to 1050°C. Pre-roll the perforated blank 2 into a rectangular ring blank 3. Preheat the core roll to 400°C, the main roll to 300°C, increase the forging speed to 10 mm / s, and forge the single piece forging time to 3 minutes. Pre-rolling deformation: 30%; 4) Preparation of special-shaped blank 4 by tire membrane: Spray lubricant on rectangular ring blank 3 and heat it to 960°C, preheat the tire membrane core mold temperature to 400°C, the outer mold temperature to 300°C, and press down at a speed of 20 mm / s to obtain special-shaped blank 4; 5) Final rolling: Spray insulation coating on the special-shaped blank 4 and heat it to 1030°C. Roll the special-shaped blank 4. Preheat the core roller to 400°C and the main roller to 200°C. Increase the forging speed by 10 mm / s and forge the single piece for 3 minutes to obtain the special-shaped ring 5. 6) Bulging: The special-shaped ring 5 is heated to 950°C, the preheating mold temperature is 400°C, the bulging speed is 6 mm / s, and the bulging amount is 3% to obtain the split casing ring 6; 7) Initial rough machining and surface protection: Rough machining is performed on the surface of the split receiver ring 6, and a thermal insulation coating is applied to its outer surface with a thickness of approximately 2 mm. The inner surface is not coated with the coating; 8) performing solution treatment and aging heat treatment on the split casing ring 6; 9) Secondary rough machining and cutting: The split receiver ring 6 is subjected to secondary rough machining and cut by wire cutting at a cutting speed of 3 cm / min.
[0009] like Figure 2 As shown, the residual stress distribution of the split casing ring produced in this embodiment is that the residual stress of the inner and outer ring surfaces is basically the same, and the cut deformation is 0.8 mm. In the figure: the dot line is the inner ring surface, and the square line is the outer ring surface.
[0010] like Figure 3 As shown in the figure, the residual stress distribution of the split receiver ring produced by the original preparation process has a large difference in residual stress between the inner and outer ring surfaces, and the cut deformation is 4.3mm. In the figure: the dotted line is the inner ring surface, and the square line is the outer ring surface.
Claims
1. A method for forming a high-temperature alloy split casing ring with low notch deformation, characterized in that: The steps include: 1) The forging of the split receiver ring is formed by ring rolling of die forged special-shaped billets. The difference in deformation of different parts of the forging is ≤5%. The die forging heating temperature is 955~995℃; 2) During die forging and ring rolling, the die temperature in contact with the inner ring surface of the blank is 400~500℃; 3) During the bulging process, the billet heating temperature is set to 940~990℃, and the bulging deformation is set to 1~4%; 4) During heat treatment cooling, apply thermal insulation coating on the outer ring surface of the blank or place a high-temperature workpiece; 5) When cutting the split receiver ring, use slow wire cutting and control the cutting rate to 1~5cm / min.
2. The method for forming a high-temperature alloy split casing ring with low notch deformation according to claim 1, characterized in that: In the step 4), the thickness of the thermal insulation coating is 1-2 mm.