Composite turbine disk profiling preform and forming method thereof

Abstract

The present application relates to a kind of composite turbine disk profiled preform and its forming method, including variable thickness polar coordinate fabric weaving, fabric ply and ply fabric stitching.The variable thickness polar coordinate fabric is by adjusting and optimizing weaving parameter, make polar coordinate fabric present the appearance of thickness change along radial direction, and weaving parameter can be optimized, accurately control the thickness of variable thickness polar coordinate fabric at different radius position, complete first thickness control.The ply fabric stitching, according to the direction of blade determines the position of suture, by a variety of suture trajectory directional introduction suture yarn, avoid the cutting of suture yarn after composite material forming, and complete second thickness control.Through variable thickness polar coordinate fabric weaving, fabric ply and ply fabric stitching etc. Process method, realize the optimization of turbine disk composite preform forming, reach variable thickness profile effect.Through in disc body position, turbine disk effectively reduces weight, and directional fiber reinforcement is carried out to turbine blade radial, effectively avoid the decline of material performance caused by the existing preform forming turbine disk after multiple cutting forming.

Description

Technical Field

[0001] This invention relates to a composite material turbine blade disk profiled preform and its molding method. Background Technology

[0002] Fiber-reinforced composite materials are increasingly widely used in aerospace, vehicle transportation, and other fields. High-performance fiber preforms are the skeleton materials of composite materials. Developing turbine bladed disk preforms with lightweight structures, high temperature resistance, and excellent overall mechanical properties plays a crucial role in breaking through the technological barriers in aero-engine development and promoting the development of the aero-engine industry. Fiber orientation reinforcement has a significant impact on the mechanical anisotropy of the composite material after preform molding. In near-circular composite materials for turbine bladed disks, the fibers within the preform need to be oriented. Turbine bladed disk composite preforms include the disk body region and the outer blade region. Existing technologies mostly use fabric preforms with uniformly distributed fibers to create integral turbine bladed disks of equal thickness, without oriented fiber reinforcement in the subsequently processed blade region and lacking further weight reduction measures. This results in structural defects in the preform, affecting the quality of the finished turbine bladed disk.

[0003] In actual operating conditions, turbine bladed disks typically reduce weight and improve performance by altering the disk's structural thickness; therefore, the disk is not of uniform thickness. Current technologies for turbine bladed disk preforms do not address the varying thickness characteristics of the preform. To meet the assembly requirements of composite turbine bladed disks and the demands of actual operating conditions, the final turbine bladed disk made from composite materials still requires multiple machining processes, including machining of the blades and disk. During machining, the complex internal structure and interactions between the fibers and matrix of composite materials can easily lead to fiber detachment and pull-out, significantly impacting the performance of the formed turbine bladed disk and affecting the yield rate. While using composite material preform structures with contour-following effects can significantly reduce subsequent machining and yield higher-performance composite parts, further contour-following structural design of the preform structure is still necessary.

[0004] Prior art patent application CN201810727285.7 discloses a weaving method and equipment for planar polar coordinate fabric. Through a polar weaving method, fiber bundles are interwoven in a circumferential and radial direction, allowing the fiber bundles to achieve the optimal load-bearing position in a circular weave. Prior art patent application 202211735832.9 discloses a turbine bladed disk preform and its weaving method, involving the introduction of circumferential and radial yarns to form a turbine bladed disk preform of uniform thickness. The aforementioned prior art applications do not address the variable thickness contour design of the turbine bladed disk preform, still requiring further processing and forming, making it difficult to avoid structural defects caused by processing allowances. Planar polar coordinate fabric is particularly suitable for high-speed rotating load-bearing composite material components such as turbine bladed disks, but the aforementioned inventions do not provide process design or further weaving parameter optimization for the preform formed from planar polar coordinate fabric, making it difficult to meet the requirements of actual working conditions. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the technical problem this invention aims to solve is to provide a composite material turbine blade disk contour preform and its molding method. The contour preform comprises a disk area and a blade processing area. The local thickness of a single-layer polar coordinate fabric is controlled by changing the local yarn weaving density. Furthermore, multiple layers of variable-thickness polar coordinate fabric are laid up and then directionally sewn with stitching yarns to control the local thickness of the disk area and blade processing area, thereby forming the contour preform. The polar coordinate fabric comprises two systems of yarns: circumferential yarns and radial yarns. The circumferential yarns are woven in an Archimedean spiral from the center outwards, while the radial yarns are uniformly introduced into the weaving structure as the radius of the polar coordinate fabric increases.

[0006] The stitching yarns are sewn along directional stitching tracks. The stitching yarns in the disk area and the blade processing area are sewn together using different types of stitching tracks, including circumferential stitching tracks and radial stitching tracks. The thickness of the conformal preform is changed along the radial direction of the turbine disk by altering the polar coordinate fabric weaving parameters and controlling the introduction of stitching yarns. The overall structure of the preform is a quasi-2.5D structure formed by the radial and circumferential yarns of each layer of polar coordinate fabric, as well as the stitching yarns.

[0007] Preferably, the composite material turbine disk conformal preform is characterized in that the specific stitching trajectory is distributed in the disk area, the stitching trajectory is along the circumference of the turbine disk preform, the trajectory shape is a nested ring, and the stitching yarn is introduced by needle along the Z direction of the preform and stitched along the stitching trajectory.

[0008] Preferably, the composite material turbine disk conformal preform is characterized in that the specific stitching trajectory is radially distributed at the transition position between the disk body and the blade processing area and in the blade processing area. The stitching trajectory is radial along the turbine disk preform, the trajectory shape is outwardly radial, and the stitching trajectory is located in the blade area of ​​the final formed composite material turbine disk. The blade is reinforced by directional stitching yarn, and the stitching yarn is introduced by needle along the Z direction of the preform and stitched along the stitching trajectory.

[0009] Preferably, the composite material turbine disk conformal preform is characterized in that the specific stitching trajectory is radially distributed at the transition position between the disk body and the blade processing area and in the blade processing area. The stitching trajectory is radial along the turbine disk preform, the trajectory shape is outwardly radial, and the stitching trajectory is located in the blade area of ​​the final formed composite material turbine disk. The blade is reinforced by directional stitching yarn, and the stitching yarn is stitched along the inclined direction of the preform blade and along the stitching trajectory.

[0010] Preferably, the composite material turbine disk conformal preform is characterized in that the radial yarn, circumferential yarn, and stitching yarn are made of high-performance fibers such as carbon fiber, silicon carbide fiber, and silicon nitride.

[0011] The technical solution of this invention to solve the problem of preform forming technology is to provide a method for forming a composite material turbine blade disk contour preform, characterized in that the method includes the following steps:

[0012] Step 1: Based on the requirements of the contour prefabrication body, determine the polar coordinate fabric weaving parameters, the number of layers, and complete the weaving of the variable thickness polar coordinate fabric:

[0013] Based on the thickness requirements of the composite preform of the turbine bladed disk at different radii, the thickness and number of polar coordinate fabric layers at different radii are determined. Based on the determined thicknesses of the single-layer polar coordinate fabric at different radii, the weaving parameters of the polar coordinate fabric at different radii are calculated. The arrangement of the circumferential and radial yarns of the polar coordinate fabric is planned according to the weaving parameters, and the weaving parameters of a single piece of polar coordinate fabric are determined. The polar coordinate fabric is then woven using the polar coordinate weaving method. The fabric parameters can be optimized according to the thickness variations of the turbine bladed disk. The local thickness can be adjusted by changing the density of the single piece of polar coordinate fabric to control the local fabric tightness, thus performing the first thickness control of the turbine bladed disk preform.

[0014] Step 2, Polar coordinate fabric layup:

[0015] According to the preset number of polar coordinate fabric layers, the woven single piece of polar coordinate fabric is layered. During the layering process of each polar coordinate fabric, the center of the fabric is aligned and the relative positions of the circumferential yarns between each layer of polar coordinate fabric are aligned.

[0016] Step 3: Orient and stitch the precast body according to different working conditions.

[0017] After the polar coordinate fabric is laid up, directional stitching is performed using stitching yarn. The stitching trajectory of the stitching yarn is determined based on the blade position and disk size of the final turbine disk, and the stitching yarn is introduced through stitching. Following the predetermined stitching trajectory, the stitching process is referenced to the preset thickness of the preform, and the force of each needle insertion is controlled. The local thickness of the preform after stitching is continuously corrected, and a second thickness control is performed until the preset thickness requirement of the preform is finally met.

[0018] Preferably, the composite material turbine blade disk conformal preform is characterized in that the method for calculating the polar coordinate fabric weaving parameters and optimizing the parameters at different radius positions in step one is as follows:

[0019] 1. Measure the initial width and thickness of the unwoven yarn and determine the target thickness of the weaving area.

[0020] 2. Determine the yarn weaving state, i.e. the yarn crimping state of the circumferential and radial yarns, based on the initial thickness and the target thickness of the weaving area. Determine the tightness of the local area of ​​the fabric under this weaving state based on empirical values.

[0021] 3. Calculate the fabric density of the radial and circumferential yarns based on the fabric tightness and the parameters of the knitting yarns.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] (1) This invention addresses the design requirements of turbine bladed disks under actual operating conditions by proposing for the first time a composite material turbine bladed disk with variable thickness contouring preform and its molding method. By controlling the weaving parameters of polar coordinate fabric and introducing sewing yarns, the structural control of the composite material turbine bladed disk contouring preform is achieved, forming the variable thickness characteristic of the contouring preform. This solves the problem that existing medium-thickness composite material turbine bladed disk preforms cannot meet the requirements of actual operating conditions, further reduces machining allowance, and effectively avoids structural defects caused by multiple cutting processes after the preform is formed into a composite material turbine bladed disk.

[0024] (2) This invention designs multiple stitching paths and introduces stitching yarns with multiple stitching paths through Z-axis stitching to directionally reinforce the stitching yarns in the turbine disk center and blades. This effectively avoids cutting the stitching yarns in the blade positions of the composite material formed by existing preforms during machining, and further improves the mechanical properties of the turbine disk formed by the conformal preform. Attached Figure Description

[0025] Figure 1 This is a front view of the cross-sectional position of the disk center of the composite material turbine disk conformal preform of the present invention;

[0026] Figure 2 This is a schematic diagram of the polar coordinate fabric structure of the present invention;

[0027] Figure 3 This is a schematic diagram of the stitching trajectory of the composite material turbine blade disk conformal preform of the present invention;

[0028] Figure 4 This is a schematic diagram illustrating vertical and oblique threading of the sewing yarn according to an embodiment of the present invention; Detailed Implementation

[0029] Specific embodiments of the present invention are given below. These specific embodiments are only used to further illustrate the present invention in detail and do not limit the scope of protection of the claims of the present invention.

[0030] This invention provides a composite material turbine bladed disk contour preform and its molding method. The contour preform comprises a disk region 1 and a blade processing region 2. The contour preform is formed by layering multiple layers of variable-thickness polar coordinate fabric, followed by directional stitching with stitching yarns to control the local thickness of the disk region 1 and the blade processing region 2. The single-piece polar coordinate fabric comprises two systems of yarns: circumferential yarns 3 and radial yarns 4. The circumferential yarns 3 are woven in an Archimedean spiral from the center outwards, while the radial yarns 4 are uniformly introduced into the woven structure as the radius of the single-piece polar coordinate fabric increases.

[0031] The stitching yarns of the conformal preform are sewn along directional stitching tracks. The stitching yarns in disk region 1 and blade processing region 2 are sewn together using different types of stitching tracks, including circumferential stitching track 5 and radial stitching track 6. The thickness of the conformal preform is along the radial direction of the turbine disk and is changed by altering the weaving parameters of the single-layer polar coordinate fabric and controlling the introduction of stitching yarns. The overall structure of the preform is a quasi-2.5D structure formed by radial yarns 4 and circumferential yarns 3 of each single-layer polar coordinate fabric, as well as the stitching yarns.

[0032] The thickness of the single-piece polar coordinate fabric is controlled by changing the local yarn density of the circumferential yarn 3 and the radial yarn 4. In the specific sewing trajectory, the circumferential sewing trajectory 5 is distributed in the disk area 1. The sewing trajectory is along the circumference of the turbine disk preform, and the trajectory shape is a nested ring. The sewing yarns are all introduced by needles along the Z direction of the preform and sewn along the specific sewing trajectory.

[0033] In operating condition one, i.e., under normal operating conditions, specific radial stitching tracks are distributed at the transition position between the disk and blade processing area 2, as well as in blade processing area 2. The stitching tracks are radially along the turbine disk preform, with an outward radial shape, and are located within the blade area of ​​the final molded composite material. The blade is reinforced by directional stitching yarn. The stitching yarn is a vertical threaded yarn 601, which is introduced along the Z-axis of the preform and stitched along the stitching tracks.

[0034] Condition 2, where the blade processing angle is large, conventional threading methods are insufficient to meet the requirements. Specific radial stitching tracks are distributed at the transition between the disk and blade processing areas (2) and within the blade processing area (2). The stitching tracks are radially distributed along the turbine disk preform, with an outward radial shape. The stitching tracks are located within the blade area of ​​the final molded composite material, and the blade is reinforced by directional stitching. The stitching tracks are obliquely threaded 602, all stitched along the blade's tilt direction and along the stitching tracks.

[0035] Throughout the process, the radial yarn, circumferential yarn, and stitching yarn can be made of high-performance fibers such as carbon fiber, silicon carbide fiber, and silicon nitride.

[0036] This invention also provides a method for forming a composite material turbine blade disk contour preform, characterized in that the method includes the following steps:

[0037] Step 1: Based on the requirements of the contour prefabrication body, determine the polar coordinate fabric weaving parameters and the number of layers, and complete the weaving of the variable thickness polar coordinate fabric:

[0038] Based on the thickness requirements of the composite preform of the contoured turbine disk at different radii, the thickness and number of polar coordinate fabric layers at different radii are determined. Based on the determined thicknesses of the single-layer polar coordinate fabric at different radii, the weaving parameters of the polar coordinate fabric at different radii are calculated. The arrangement of the circumferential yarns 3 and radial yarns 4 of the polar coordinate fabric is planned according to the weaving parameters, and the polar coordinate fabric is woven using the polar coordinate weaving method. The fabric parameters can be optimized according to the thickness variation of the turbine disk body. The local thickness can be adjusted by changing the density of a single piece of polar coordinate fabric to control the local fabric tightness, thus performing the first thickness control of the contoured turbine disk preform.

[0039] Step 2, Polar coordinate fabric layup:

[0040] Based on the preset number of polar coordinate fabric layers, the woven single piece of polar coordinate fabric is layered, ensuring that the center of the fabric is aligned during the layering process of each polar coordinate fabric layer.

[0041] Step 3: Oriented stitching and shaping

[0042] Condition 1: In this directional stitching method, all stitching yarns are stitched along the thickness direction of the preform. During the stitching process, the stitching yarns of the conforming preform are introduced by needle insertion along the Z-axis. At the disk position of the conforming preform, circumferential stitching trajectory 5 is used, with the stitching trajectory along the circumference of the turbine disk preform. In the transition area between the disk and the blade, and at the blade position, radial stitching trajectory 6 is used, with the stitching trajectory along the radial direction of the turbine disk preform and located within the blade area of ​​the final formed composite material, thus directionally reinforcing the blades through the stitching yarns. For the polar coordinate fabric after layup, directional stitching is performed using stitching yarns. The stitching trajectory of the stitching yarns is determined according to the blade position and disk size of the final formed turbine disk, and the stitching yarns are introduced through Z-axis stitching. According to the predetermined stitching trajectory, during the stitching process, the needle insertion force is controlled with reference to the preset thickness of the conforming preform, continuously correcting the local thickness of the preform after stitching, performing a second thickness control until the preset thickness requirement of the conforming preform is finally met, thus forming the required composite material turbine disk conforming preform.

[0043] In Condition 2, based on Condition 1, the directional stitching method is changed to partially stitching the stitching yarn along the thickness direction of the conforming preform, and partially stitching the stitching yarn along the blade tilt direction at the blade processing position. During the stitching process, the stitching yarn of the conforming preform is introduced into the disk body along the Z-axis. At the blade position, the stitching yarn is introduced along the blade tilt angle. The stitching yarn is arranged in the polar coordinate fabric layers in the same direction as the blade tilt. At the disk position of the conforming preform, circumferential stitching trajectory 5 is used, with the stitching trajectory along the circumference of the turbine disk preform. In the transition area between the disk and the blade, and at the blade position, radial stitching trajectory 6 is used, with the stitching trajectory along the radial direction of the turbine disk preform and located within the blade area of ​​the final molded composite material. The blade is directionally reinforced by the stitching yarn. For the polar coordinate fabric after the layup is completed, directional stitching is performed using stitching yarn. The stitching trajectory of the stitching yarn is determined according to the blade position and the size of the turbine disk body in the final molded turbine disk, and the stitching yarn is introduced through Z-axis stitching. Following the predetermined stitching trajectory, the stitching process is carried out with reference to the preset thickness of the preform, and the force of each stitch is controlled. The local thickness of the preform after stitching is continuously corrected, and a second thickness control is performed until the preset thickness requirement of the preform is finally met, thus forming the required composite material turbine blade disk preform.

[0044] Preferably, the composite material turbine blade disk conformal preform is characterized in that the method for calculating the polar coordinate fabric weaving parameters and optimizing the parameters at different radius positions in step one is as follows:

[0045] 1. Measure the initial width and thickness of the unwoven yarn and determine the target thickness of the weaving area.

[0046] 2. Determine the yarn weaving state, i.e. the yarn crimping state of the circumferential and radial yarns, based on the initial thickness and the target thickness of the weaving area. Determine the tightness of the local area of ​​the fabric under this weaving state based on empirical values.

[0047] 3. Calculate the fabric density of the radial and circumferential yarns based on the fabric tightness and the parameters of the knitting yarns.

[0048] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A composite material turbine blade disk contour preform, characterized in that, The conformal preform includes a disc area (1) and a blade processing area (2); the local thickness of the single-layer polar coordinate fabric is controlled by changing the local yarn weaving density, and further, the local thickness of the disc area (1) and the blade processing area (2) is controlled by directional sewing of multiple layers of polar coordinate fabric after lay-up, thereby forming the conformal preform; the single-layer polar coordinate fabric includes two systems of yarns: circumferential yarn (3) and radial yarn (4). The circumferential yarn (3) is woven in an Archimedean spiral from the center outwards, and the radial yarn (4) is uniformly introduced into the weaving structure as the radius of the polar coordinate fabric increases; the sewing The yarn is sewn along the directional sewing trajectory. The sewing yarn in the disk area (1) and the blade processing area (2) is sewn through different types of sewing trajectories, including the circumferential sewing trajectory (5) distributed in the disk area (1) and the radial sewing trajectory (6) distributed in the transition position between the disk and the blade processing area (2) and the blade processing area (2). The thickness of the conformal preform is changed along the radius direction of the turbine blade disk by changing the polar coordinate fabric weaving parameters and controlling the introduction of sewing yarn. The overall structure of the preform is a 2.5D-like structure formed by the circumferential yarn (3) and radial yarn (4) of each layer of polar coordinate fabric and the sewing yarn.

2. The composite material turbine blade disk conformal preform according to claim 1, characterized in that... The circumferential stitching trajectory (5) is distributed in the disk area (1). The stitching trajectory is along the circumference of the turbine disk preform. The trajectory shape is a nested ring. The stitching yarn is a vertical thread (601). All of them are introduced by needles along the Z direction of the preform and stitched along the stitching trajectory.

3. The composite material turbine blade disk conformal preform according to claim 1, characterized in that... The radial stitching trajectory (6) is distributed at the transition position between the disk body and the blade processing area (2) and the blade processing area (2). The stitching trajectory is radial along the turbine blade disk preform, and the trajectory shape is outwardly radial. The stitching trajectory is located in the blade area of ​​the final formed composite material. The blade is reinforced by the stitching yarn. The stitching yarn is obliquely threaded (602) and is stitched along the inclined direction of the preform blade and along the stitching trajectory.

4. The composite material turbine blade disk conformal preform according to claim 1, characterized in that... The radial yarn (4), circumferential yarn (3), and stitching yarn are made of carbon fiber, silicon carbide fiber, or silicon nitride fiber.

5. A method for forming a composite material turbine bladed disk contour preform, characterized in that, The method includes the following steps: Step 1: Based on the requirements of the contour prefabrication body, determine the polar coordinate fabric weaving parameters and the number of layers, and complete the weaving of the variable thickness polar coordinate fabric: Based on the thickness requirements of the composite material preform of the turbine blade disk at different radii, the thickness of the single-layer polar coordinate fabric at different radii and the number of polar coordinate fabric layers are determined respectively; based on the determined thickness of the single-layer polar coordinate fabric at different radii, the polar coordinate fabric weaving parameters at different radii are calculated; based on the weaving parameters, the arrangement of the circumferential yarn (3) and radial yarn (4) of the polar coordinate fabric is planned, the polar coordinate fabric weaving parameters are determined, and the polar coordinate fabric is woven using the polar coordinate weaving method; based on the thickness change of the turbine blade disk, the fabric parameters are optimized, and the fabric density of the polar coordinate fabric is changed to control the local fabric tightness to adjust the local thickness, and the first thickness control of the composite turbine blade disk preform is carried out; Step 2, Polar coordinate fabric layup: According to the preset number of polar coordinate fabric layers, the woven single-layer polar coordinate fabric is laid up. During the laying up of each layer of polar coordinate fabric, the center of the fabric is aligned and the relative positions of the circumferential yarns between each layer of polar coordinate fabric are aligned. Step 3: Oriented suturing and shaping: After the polar coordinate fabric is laid up, it is oriented and sewn with sewing yarn. The sewing trajectory of the sewing yarn is determined according to the blade position and the size of the turbine disk. This includes the circumferential sewing trajectory (5) distributed in the disk area (1) and the radial sewing trajectory (6) distributed in the transition position between the disk and the blade processing area (2) and the blade processing area (2). The sewing yarn is introduced by sewing. For the radial sewing trajectory (6), the sewing yarn is introduced by needle along the Z direction of the preform and vertically threaded (601), or introduced by needle along the blade tilt direction of the preform and obliquely threaded (602). According to the predetermined sewing trajectory, the sewing process is referenced to the preset thickness of the conforming preform. The sewing force is controlled each time, and the local thickness of the preform after sewing is continuously corrected. The second thickness control is performed until the preset thickness requirement of the conforming preform is finally met.

6. The method for forming a composite material turbine blade disk contour preform according to claim 5, characterized in that, Step 1, which calculates the polar coordinate fabric weaving parameters at different radius positions and the method for parameter optimization, specifically includes:

1. Measure the initial width and thickness of the unwoven yarn and determine the target thickness of the weaving area; 2. Based on the initial thickness and the target thickness of the weaving area, determine the yarn weaving state, that is, the yarn buckling state of the circumferential yarn (3) and the radial yarn (4), and determine the tightness of the local area of ​​the fabric under this weaving state based on empirical values.

3. Calculate the fabric density of the circumferential yarn (3) and the radial yarn (4) based on the fabric tightness and the parameters of the knitting yarn.

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