A stress homogenization process for high temperature alloy annular parts

Abstract

The application discloses a stress homogenization process for a high-temperature alloy annular piece, and comprises the following steps: air cooling a high-temperature alloy annular forge piece after solid solution heat treatment, and performing afterheat shaping during the air cooling process; (1) the shaping pass is designed as multiple passes, the single-pass deformation amount is controlled to be 0.4%-0.8%, and the total deformation amount is less than or equal to 2%; (2) the shaping time is controlled to be less than or equal to 50s, and the final shaping temperature is greater than or equal to 900 DEG C. Through simulation and analysis, the stress generation time point of the high-temperature alloy annular piece during forging is determined, the afterheat shaping is directly performed after the solid solution heat treatment, the shaping is completed in a very short time, the stress homogenization is ensured, and the high-temperature alloy annular piece forging has high technical value.

Description

Technical Field

[0001] This invention discloses a stress homogenization process for high-temperature alloy ring parts, belonging to the field of high-temperature alloy forging. Background Technology

[0002] Currently, the cost pressure on military and civilian aircraft engines is increasing. In order to continuously reduce the cost of raw materials, the design of components is becoming more and more complex, and with the improvement of material quality, the wall thickness of products is getting thinner and thinner.

[0003] Currently, in order to meet the requirements when producing components for this type of aero-engine, the following two methods are generally used: increasing the blank allowance; and normal air cooling, which can easily increase the phenomenon of uneven stress.

[0004] The above method has the following drawbacks:

[0005] 1) Inefficient, with a large amount of allowance added, subsequent processing time will also increase accordingly;

[0006] 2) Solid solution treatment can easily generate new stress, which can easily cause deformation during subsequent part processing.

[0007] In addition, existing technologies also employ solution heat treatment followed by cold expansion forming and aging heat treatment. This method takes too long to process and cannot fully achieve the required stress uniformity. Summary of the Invention

[0008] To address the aforementioned challenges, this invention primarily solves the following problems:

[0009] (1) Thin-walled, large-size high-temperature alloy materials are expensive. By shaping to reduce ovality, the machining allowance can be reduced.

[0010] (2) Reduce the uneven stress generated during the solution treatment process, thereby preventing machining deformation.

[0011] During production practice, the inventors discovered that deformation is easily generated during the machining process. After analysis, the stress was mainly generated after solution treatment. Through simulation analysis, the time point of stress generation was determined, and the time point of the shaping stage was determined based on the time point, thereby controlling the stress and reducing deformation.

[0012] This invention designs a stress homogenization process for high-temperature alloy ring parts, which eliminates the need for shaping during machining, and only requires residual heat shaping after heat treatment, without the need for aging heat treatment.

[0013] The technical solution of the present invention is as follows:

[0014] A stress homogenization process for a high-temperature alloy ring component includes the following steps:

[0015] The high-temperature alloy ring forgings that have undergone solution heat treatment are air-cooled, and residual heat is used for shaping during the air-cooling process.

[0016] (1) The forming pass is designed as a multi-pass process, with the deformation amount of a single pass controlled at 0.4%-0.8%, and the total deformation amount ≤2%;

[0017] (2) The shaping time should be controlled within 50 seconds and the final shaping temperature should be ≥900℃.

[0018] Preferably, the specific steps of step (1) above are as follows:

[0019] (1-1) The forging is transferred to the expansion machine by tooling, and the transfer time is ≤20s;

[0020] (1-2) The expanding forming machine starts working. The deformation amount of the first expansion forming is controlled at 0.4%-0.8%. Then the expanding forming machine is released, and the forging springs back by 0.18-0.22%.

[0021] (1-3) Repeat step (1-2) twice to end the expansion. The total deformation is calculated based on the inner diameter of the hole, and the total deformation is 1.34-1.68%.

[0022] The beneficial effects of this invention are:

[0023] This invention, through simulation analysis, determines the stress generation time point of high-temperature alloy ring parts during forging. By directly performing residual heat shaping after solution heat treatment, the shaping is completed in a very short time, ensuring stress uniformity. This invention has high technical value for the forging of high-temperature alloy ring parts. Attached Figure Description

[0024] Figure 1 This is a diagram showing the tangential stress field distribution of the annular component during the solution treatment process in Example 1, over a period of 5 seconds.

[0025] Figure 2 This is a diagram showing the tangential stress field distribution of the annular component during the solution treatment process in Example 1, over 10 seconds.

[0026] Figure 3 This is a diagram showing the tangential stress field distribution of the annular component during the solution treatment process in Example 1 for 20 seconds.

[0027] Figure 4 This is a diagram showing the tangential stress field distribution of the annular component during the solution treatment process in Example 1 over 50 seconds.

[0028] Figure 5 This is the equivalent stress distribution of the annular component during the forming process in Example 1, which is 1 second.

[0029] Figure 6 This refers to the equivalent stress distribution of the annular component during the forming process in Example 1 over 2 seconds.

[0030] Figure 7 This is the equivalent stress distribution of the annular component during the shaping process in Example 1 over 3 seconds;

[0031] Figure 8 This is the equivalent stress distribution of the annular component during the forming process in Example 1 over 4 seconds;

[0032] Figure 9 This is the equivalent stress distribution of the annular component during the forming process in Example 1 over 5 seconds;

[0033] Figure 10 This is the equivalent stress distribution of the annular component during the shaping process in Example 1 over 6 seconds;

[0034] Figure 11 This is the heating curve of step S81 in Example 2;

[0035] Figure 12 This is the heating curve of step S111 in Example 2;

[0036] Figure 13 This is the solution temperature control curve for step S14 in Example 2. Detailed Implementation

[0037] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention. Example 1

[0038] The inventors simulated the stress distribution of the ring-shaped component during the solution treatment and shaping processes.

[0039] like Figure 1-4 As shown, during the solution treatment process of the ring part (the residual stress is generated during the solution cooling process, and the stress is greatest at the very beginning of the cooling process from high temperature to low temperature. The reason for dividing it into two stages of 20 seconds and 50 seconds is because the simulation process shows that the definition of nodes is not so accurate when distinguished by the naked eye), the stress begins to be uneven in the first 20 seconds of the cooling process (air cooling). The uneven stress begins to expand within 20 seconds to 50 seconds. Therefore, the optimal shaping time should be completed within 50 seconds.

[0040] like Figure 5-10 As shown, during the residual heat shaping process, the stress begins to homogenize in the first 3 seconds. Example 2

[0041] A stress homogenization process for a high-temperature alloy ring component includes the following steps:

[0042] S1, Material feeding

[0043] Standard part blanking dimensions: Φ300(+3 / -2) × 534(+5 / 0), Standard part blanking weight (kg): 337(+1 / -1)kg;

[0044] Sample blanking dimensions: Φ300(+3 / -2) × 596(+5 / 0), Sample blanking weight (kg): 376(+1 / -1)kg;

[0045] S2, Chamfer

[0046] Chamfer size: R20

[0047] S3, upsetting, punching

[0048] S4, Forging Heating

[0049] S41. Heating and heat preservation coefficient: The heat preservation time for cold material during heating is calculated as 0.7 min / mm, and for hot material as 0.4 min / mm;

[0050] S42. Hot material reheating system: The hot material reheating temperature is the same as the current cold material heating temperature, and the holding time is based on the hot material heating holding coefficient.

[0051] S5, upsetting, punching

[0052] S51. Forging process:

[0053] Standard parts are upset to ~Φ430×260±5, and punched with Φ180 holes;

[0054] The raised part is upset to ~Φ430×290±5, and the punched hole is Φ180;

[0055] The thickness of the perforated substrate is ≤75mm;

[0056] S52. Finishing temperature (°C): ≥900°C;

[0057] S53. Forging passes: 1-2 passes;

[0058] S6, Machine-made Cleaning

[0059] S61. Machining requirements: The maximum allowable machining depth for the inner hole is Φ190±5. Defects such as punching and connecting skin should be removed by machining. The edges of the inner hole should be rounded to R10-R15.

[0060] S62. Machining reference: During machining, the inner hole is used as the reference for rounding.

[0061] S63. Cleaning requirements: Visually inspect the surface for defects such as cracks. If defects are found, arrange for coloring and polishing to clean the surface until there are no defects. The width-to-depth ratio of the polished area should be ≥8.

[0062] S7, Frame-type enlarged hole

[0063] S8, Forging Heating

[0064] S81. Cold material heating regime: According to the heating curve, such as Figure 11 .

[0065] S82.TDD-01 Furnace loading amount ≤ 4; TDD-02 Furnace loading amount ≤ 9; TDD-04 Furnace loading amount ≤ 9; TDD-05 Furnace loading amount ≤ 9; TDD-06 Furnace loading amount ≤ 9; TDD-32 Furnace loading amount ≤ 9; TDD-33 Furnace loading amount ≤ 9; TDD-34 Furnace loading amount ≤ 9; TDD-42 Furnace loading amount ≤ 9; TDD-43 Furnace loading amount ≤ 9;

[0066] S83. Placement method: Lay flat;

[0067] S84. Furnace loading position requirements: Load the forgings into the furnace in sequence, with a distance of ≥50mm between each piece and a height of ≥50mm between the forging and the furnace bottom plate; record the loading position.

[0068] S9, Frame-type enlarged hole

[0069] S91. Forging process:

[0070] For standard parts, the end face is flattened to: Φ550±10×Φ350±10×253±5;

[0071] The end face of the heightened component is expanded and flattened to: Φ550±10×Φ350±10×283±5;

[0072] S92. Finishing temperature (°C): ≥900°C;

[0073] S93. Forging passes: 2-3 passes;

[0074] S94. Cooling after forging: Air cooling.

[0075] S95. Transfer time (S) ≤ 120S;

[0076] S96. Preheating fixtures: Preheating related molds before forging;

[0077] S97. Tooling temperature lower limit (°C): 250, Tooling temperature upper limit (°C): 350;

[0078] S98. Forging speed: Control the reduction amount, the reduction amount per hammer blow ≤50mm;

[0079] S99. Crack Treatment: If cracks appear during forging, stop forging, air cool to room temperature and clean the cracks, with a width-to-depth ratio ≥ 8.

[0080] S10, rolled ring

[0081] S11, Forging Heating

[0082] S111. Cold material heating regime: According to the heating curve, such as Figure 12 As shown;

[0083] S112.TDD-04 Furnace loading amount ≤9; TDD-11 Furnace loading amount ≤9; TDD-12 Furnace loading amount ≤9; TDD-13 Furnace loading amount ≤9; TDD-18 Furnace loading amount ≤4; TDD-27 Furnace loading amount ≤4; TDD-32 Furnace loading amount ≤9; TDD-33 Furnace loading amount ≤9; TDD-41 Furnace loading amount ≤9;

[0084] S113. Placement method: Lay flat;

[0085] S114. Furnace loading position requirements: Load the forgings into the furnace in sequence, with a distance of ≥50mm between each piece and a height of ≥50mm between the forging and the furnace bottom plate. Stacking is allowed (but not overlapping). Record the loading position.

[0086] S12, rolled ring

[0087] S121. Forging process:

[0088] First fire of ring rolling

[0089] For standard parts, the ring is rolled to: Φ685±5×Φ535±5×250±5;

[0090] The heightened component is rolled to: Φ685±5×Φ535±5×280±5;

[0091] Hot material is returned to the furnace and kept warm for 30 minutes;

[0092] Second fire of ring rolling

[0093] For standard parts, the ring is rolled to: Φ989±5×Φ890±5×247±5;

[0094] The heightened component is rolled to: Φ989±5×Φ890±5×277±5;

[0095] S122. Finishing temperature (°C): ≥900°C;

[0096] S123. Forging fire level: 2 fires;

[0097] S124. Post-forging cooling: air cooling;

[0098] S125. Transfer time (S) ≤ 120S;

[0099] S126. Preheating fixture: Preheat the main and core rollers of the ring mill before transfer;

[0100] S127. Lower limit of tooling temperature (°C): 250, Upper limit of tooling temperature (°C): 350;

[0101] S128. Crack treatment: If cracks appear during forging, stop forging, air cool to room temperature and clean the cracks, with a width-to-depth ratio ≥ 8.

[0102] S13, Heat Treatment

[0103] S14, solid solution

[0104] S141.TRD-05 Furnace loading amount ≤12; TRD-06 Furnace loading amount ≤12; TRD-08 Furnace loading amount ≤12; TRD-17 Furnace loading amount ≤12; TRD-13 Furnace loading amount ≤8; TRD-14 Furnace loading amount ≤8; TRD-16 Furnace loading amount ≤2;

[0105] S142. Placement method: Stacked; Number of stacked layers ≤ 2;

[0106] S143. Requirements for heating furnaces: They shall meet the requirements for Class III furnaces in GJB509;

[0107] S144. Furnace loading position requirements: Load the forgings into the furnace in sequence, with a distance of ≥50mm between each piece and a height of ≥50mm between the forging and the furnace bottom plate; record the loading position.

[0108] Temperature control of solid solution, such as Figure 13 As shown.

[0109] S15, Plastic Surgery

[0110] Equipment: 4000T shaping machine

[0111] The amount of plastic surgery performed per session is 0.4%-0.8%, and the total amount of plastic surgery performed is no more than 2%.

[0112] Specific steps

[0113] S151. The forging is air-cooled and then transferred to the expansion machine with special tooling. The transfer time is ≤20s.

[0114] S152, The expanding machine starts working, expanding 7mm in the first pass, the expanding machine releases pressure, and the forging springs back 2-3mm;

[0115] The second pass of expansion is 7mm, the expansion machine is then loosened, and the forging springs back 2-3mm;

[0116] The third pass of expansion is 7mm, the expansion machine is released, and the forging springs back 2-3mm;

[0117] The bulging process is complete. The total deformation is calculated based on the inner diameter, and the total deformation is 1.34-1.68%.

[0118] Final cosmetic surgery results in:

[0119] Standard parts up to: Φ998±5×Φ903±2×247±5;

[0120] The height of the component is increased to: Φ998±5×Φ903±2×277±5;

[0121] S153, transfer time ≤ 20s, total shaping time not longer than 50 seconds, final shaping temperature not lower than 900℃.

[0122] S16, Rough machining

[0123] Machining requirements: Forgings shall be machined according to the special roughing drawings.

[0124] The high-temperature alloy ring produced in Example 2 ensures stress uniformity.

[0125] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A process for stress homogenization of a high temperature alloy annulus, characterized in that It comprises the following steps: The high-temperature alloy ring forging after solution heat treatment is air-cooled, and the afterheat is shaped during the air-cooling process; (1) The shaping pass is designed as multiple passes, and the single-pass deformation is controlled to be 0.4%-0.8%, and the total deformation is ≤2%; (2) The shaping time is controlled to be within 50s, and the final shaping temperature is ≥900℃.

2. A process for stress homogenization of a high temperature alloy annular piece according to claim 1, characterized in that The specific steps of the step (1) are as follows: (1-1) The forging is transferred to the expander through a tooling to be shaped, and the transfer time is ≤20s; (1-2) The expander starts to work, the first-pass expander deformation is controlled to be 0.4%-0.8%, then the expander is loosened, and the forging rebounds by 0.18-0.22%; (1-3) Step (1-2) is repeated twice, the expander is stopped, and the total deformation is calculated according to the inner hole diameter, and the total deformation is 1.34-1.68%.

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