A method of vane layup and a CMC vane manufacturing method

Abstract

A blade layup method is provided, comprising the steps of: laying a plurality of layers of first fiber cloth outside a blade inner cavity mold to form a blade layer surface; when laying each layer of first fiber cloth, folding the upper side and the lower side of each layer of first fiber cloth once to form an upper edge plate layer surface and a lower edge plate layer surface, and adding a layer of second fiber cloth on each of the upper edge plate layer surface and / or the lower edge plate layer surface to form an upper edge plate secondary layer surface and / or a lower edge plate secondary layer surface; and when adding each layer of second fiber cloth, selectively folding the layer of second fiber cloth to form an assembly surface layer surface. The blade layup method described above can obtain a blade assembly surface through continuous folding. A CMC blade manufacturing method is also provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of manufacturing turbine blades of an aero-engine, in particular to the field of manufacturing turbine blades of a ceramic matrix composite material. BACKGROUND

[0002] The ceramic matrix composite material (CMC) has high specific strength, specific stiffness, light weight and corrosion resistance at high temperature, can adapt to the working environment of the hot end part of the turbine of an aero-engine, significantly improve the upper limit of the use temperature of the hot end part and the overall performance of the engine and reduce pollution emissions, and has great application prospect in the field of aero-engines. Currently, advanced aero-engine manufacturing enterprises at home and abroad have successively applied the CMC material to the hot end parts of an aero-engine, such as a combustion chamber flame tube, a turbine outer ring and a turbine blade.

[0003] Due to the difficulty in forming the ceramic matrix composite material, it is difficult to form various complex assembly structures on the traditional metal blade, so that the assembly of the ceramic matrix composite material with the metal part is limited. At present, many metal components are introduced in the assembly structure of the CMC turbine blade for assembly with the front and rear metal casing parts. However, due to the difference in the thermal expansion coefficients of the CMC and the metal material, the thermal mismatch problem caused by the difference between the metal and the CMC material is difficult to solve. In order to reduce the metal assembly structure of the CMC turbine blade, the CMC assembly surface for assembly with the front and rear metal casings needs to be increased, but due to the brittleness of the CMC material, the folding phenomenon is easy to occur, so that the fiber cloth or unidirectional tape is difficult to realize the single-side twice folding to form the assembly surface in the layering process.

[0004] Therefore, it is necessary to provide a blade layering method to solve the above problems. SUMMARY

[0005] An object of the present application is to provide a blade layering method which can obtain a blade assembly surface by means of continuous folding.

[0006] In order to achieve the above object, a blade layering method for forming a CMC blade, the CMC blade comprising a blade body, an upper edge plate and a lower edge plate, and a plurality of assembly surfaces for lapping with metal parts on the upper edge plate and the lower edge plate, characterized in that it comprises the following steps: laying a plurality of layers of first fiber cloth outside a blade inner cavity mold to form a blade body layer surface; when laying each layer of first fiber cloth, folding the upper side and the lower side of each layer of first fiber cloth once to form an upper edge plate layer surface and a lower edge plate layer surface, and adding a layer of second fiber cloth on each layer of upper edge plate layer surface and / or lower edge plate layer surface to form a second layer surface of the upper edge plate and / or a second layer surface of the lower edge plate; and when adding each layer of second fiber cloth, selectively folding the layer of second fiber cloth to form an assembly surface layer surface.

[0007] In one or more embodiments, when the first fiber cloth of each layer at the blade layer level is folded to form the upper edge plate layer level and the lower edge plate layer level, a cutout is needed, and a fiber cloth patch is used for stitching at the cutout to form a stitched fiber layer.

[0008] In one or more embodiments, a new layer of first fiber cloth is stacked on the stitched fiber layer, and the new layer of first fiber cloth is alternately stacked with the stitched fiber layer.

[0009] In one or more embodiments, after the first layer of second fiber cloth in the upper edge plate secondary layer level and / or the lower edge plate secondary layer level is folded for the first time and forms the assembly surface layer level, each subsequent layer of second fiber cloth is folded.

[0010] Another object of the present application is to provide a CMC blade manufacturing method, comprising the following steps:

[0011] S1. Perform initial structural design of the CMC blade, and obtain CMC blade strength distribution values under different temperature and pressure loads under the initial structural design;

[0012] S2. Modify the geometric parameters of the CMC blade according to the strength distribution values, obtain a secondary structural design of the blade, and obtain CMC blade strength distribution values under different temperature and pressure loads under the secondary structural design;

[0013] S3. Repeat steps S1-S2 until the final geometric parameters that meet the strength requirements are obtained;

[0014] S4. Determine the number of blade plies, the number of folded plies, and the ply sequence based on the final geometric parameters;

[0015] S5. Use the above blade ply method to perform ply, and obtain a ply blade;

[0016] S6. Perform subsequent processing on the ply blade to obtain a formed blade.

[0017] In one or more embodiments, after step S5 is completed, an outer mold is wrapped around the outermost layer of fiber cloth to preliminarily shape the ply blade.

[0018] In one or more embodiments, the geometric parameters include assembly surface thickness, assembly surface height, and assembly surface fillet.

[0019] In one or more embodiments, in step S6, the subsequent processing includes a high-temperature pyrolysis shaping link.

[0020] The above layering method realizes two-time folding of the fiber cloth or unidirectional tape on one side, provides an assembly surface for the CMC turbine blade, thereby reducing the arrangement of metal components in the assembly structure of the CMC turbine blade; further, the layering method can also realize the design of different thicknesses of the CMC turbine blade at different positions, and the thicknesses of the blade at different positions can be adjusted according to the stress and assembly space, thereby flexibly designing the structure of the CMC turbine blade and making the blade manufacturing feasible.

[0021] The above CMC blade manufacturing method realizes the flexible design and manufacturing of the blade structure by iteratively modifying the geometric parameters of the blade, obtaining design parameters with better stress distribution, and determining the number of layering, the number of folding and the layering sequence according to the design parameters. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and other features, properties and advantages of the present application will become more apparent through the following description with reference to the accompanying drawings and embodiments, in which:

[0023] Figure 1 is a schematic diagram of a CMC blade structure.

[0024] Figure 2 is a schematic diagram of part of the structure of one embodiment of a layering blade.

[0025] Figure 3 is a schematic diagram of part of the structure of another embodiment of a layering blade.

[0026] Figure 4 is a schematic diagram of the structure of an assembly surface.

[0027] Figure 5 is a schematic diagram of part of an alternating layering surface.

[0028] Figure 6 is a schematic diagram of the flow of a CMC blade manufacturing method.

[0029] SYMBOL EXPLANATION

[0030] 1 first fiber cloth

[0031] 2 second fiber cloth

[0032] 31 blade body layer surface

[0033] 32 upper edge plate layer surface

[0034] 33 lower edge plate layer surface

[0035] 34 assembly surface layer surface

[0036] 100 blade

[0037] 101 blade body

[0038] 102 upper rim plate

[0039] 103 first assembly surface

[0040] 104 second assembly surface

[0041] 105 lower rim plate

[0042] 106 third assembly surface

[0043] 107 fourth assembly surface

[0044] 108 fifth assembly surface DETAILED DESCRIPTION

[0045] The present application will be further described with reference to the accompanying drawings and specific examples, which set forth in more detail and the present application is apparently capable of being carried out in various ways other than those explicitly described herein, and skilled persons can make similar generalizations, deductions, and extrapolations from the actual application without departing from the scope of the present application, therefore the protection scope of the present application should not be limited by the specific examples.

[0046] It should be noted that these and other subsequent drawings are only examples, which are not drawn in accordance with the condition of the same scale, and should not be used as a limitation on the actual protection scope required by the present application.

[0047] Figure 1 The structural diagram of a conventional aero-engine turbine blade 100 is shown, the overall material of the aero-engine turbine blade is CMC material (Ceramic Matrix Composite), which is composed of high-strength ceramic fibers and ceramic matrix, can withstand high temperature, and has better toughness. The blade structure will be described below in combination with the XYZ coordinate axes in the figure as an example. Figure 1

[0048] The CMC blade 100 includes a blade body 101, an upper rim plate 102, and a lower rim plate 105, wherein the upper rim plate 102 and the lower rim plate 105 are located on the XOY plane, and the blade body 101 extends along the Z-axis direction. The blade 100 also includes a plurality of assembly surfaces that need to be lapped with metal components, such as the first assembly surface 103 and the second assembly surface 104 located on the upper rim plate 102 and connected with the front and rear metal casings, the fourth assembly surface 107 and the fifth assembly surface 108 connected with the front and rear metal components, and the third assembly surface 106 located on the lower rim plate 105 and connected with the metal components.

[0049] ​In the conventional blade layup process, the CMC blade 100 is formed by multi-layer layup of fiber cloth. The fiber cloth is a cloth-like material containing continuous SiC fibers, which is brittle and prone to breakage. Therefore, during the layup process, multiple edge folding of the fiber cloth is extremely prone to breakage of the fiber cloth, resulting in a complex blade layup manufacturing process, especially the manufacturing of the assembly surface.

[0050] The blade layup method disclosed in the present disclosure can realize that multiple assembly surfaces are obtained by the fiber cloth edge folding method, overcoming the above problems.

[0051] The method comprises the following steps: laying a plurality of layers of first fiber cloth 1 outside the blade inner cavity mold to form a blade body layer 31; when laying each layer of first fiber cloth 1, folding the upper side and the lower side of each layer of first fiber cloth 1 once to form an upper edge plate layer 32 and a lower edge plate layer 33, and adding a layer of second fiber cloth 2 on each layer of upper edge plate layer 32 and / or lower edge plate layer 33 to form an upper edge plate secondary layer and / or a lower edge plate secondary layer; when adding each layer of second fiber cloth 2, the second fiber cloth 2 is selectively folded to form an assembly surface layer 34.

[0052] It should be noted that the terms "first", "second", etc. used herein to define the fiber cloth are only used to facilitate the distinction of the fiber cloth in different parts, and the above terms have no special meaning, do not represent primary and secondary, have no material difference, and cannot be understood as a limitation on the scope of protection of the present application.

[0053] Specifically, the method combines Figure 6 As shown in the flowchart, first, step S51 is performed, and the first layer of fiber cloth 1 is laid outside the blade inner cavity mold. Under the support of the blade inner cavity mold (not shown in the figure), the blade inner cavity mold is wrapped to form a blade body layer 31, as shown in Figure 1 The position of the blade body 101.

[0054] The blade inner cavity mold can preferably be a component that does not need to be removed in the subsequent high-temperature shaping step of the blade, thereby simplifying the manufacturing process of the blade.

[0055] Subsequently, step S52 is performed, and the first layer of fiber cloth 1 of the blade body layer 31 is folded to obtain an upper edge plate layer 32 and a lower edge plate layer 33, as shown in Figure 1 The positions of the upper edge plate 102 and the lower edge plate 105.

[0056] Fiber cloth folding refers to folding the fiber cloth at the edge of the fiber cloth, so that the fiber cloth originally extending along the Z-axis is folded along the XOY plane, as shown in Figure 2 The A direction, thereby forming the upper edge plate 102 and the lower edge plate 105 located on the XOY plane.

[0057] In one embodiment, when the first fiber cloth on the blade surface 31 is folded over, it is necessary to cut the first fiber cloth. A fiber cloth patch is then used to sew the cuts together, forming a patched fiber layer. The cutting operation creates a gap in the original first fiber cloth 1, breaking the continuous SiC fibers within the cloth and affecting the blade strength at the cuts. Using the fiber cloth patch to sew together a patched fiber layer fills the gap, ensuring the continuity of the SiC fibers there, thereby maintaining blade strength at the cuts and enhancing the strength of the build-up layer.

[0058] When a new layer of first fiber cloth 1 is subsequently laid in multiple layers, a new layer of first fiber cloth 1 is stacked on the mending fiber layer so that the new layer of first fiber cloth 1 and the mending fiber layer are stacked alternately. The alternating stacking method can effectively improve the interlayer strength and tensile strength of the edge plate.

[0059] Continuing to step S53, a second layer of fiber cloth 2 is added on the upper edge plate layer 32 and / or the lower edge plate layer 33 to obtain the upper edge plate secondary layer 34 and / or the lower edge plate secondary layer 35. Figure 2 and Figure 3 As shown, the solid lines represent the multiple layers of first fiber cloth 1 within the blade airfoil layer 31, and the dotted lines represent the added second fiber cloth 2. On top of the upper and lower edge panel layers, the added second fiber cloth 2 forms the upper and lower edge panel secondary layers 34 and 35. Therefore, due to the added layers of second fiber cloth 2, the thickness of the upper and lower edge panels 102 and 105 is greater than that of the blade airfoil 101.

[0060] After obtaining the upper edge plate secondary layer 34 and / or the lower edge plate secondary layer 35, step S54 or S55 is performed, that is, whether the second fiber cloth 2 needs to be folded, such as Figure 2 The B direction is shown to form the assembly surface layer 34.

[0061] The selection of step S54 or S55 is related to the current thickness of the upper edge plate 102 or the lower edge plate 105. Since the forces on different surfaces of the blade are different, the designed thickness is also different, and the designed thickness can be achieved by increasing or decreasing the number of layers of fiber cloth.

[0062] Therefore, when the thickness of the upper edge plate 102 or the lower edge plate 105 meets the strength requirement, step S54 is performed to fold the second fiber cloth 2 to form the assembly surface layer 34. Figure 1 The first assembly surface 103 and the second assembly surface 104 are located on the upper edge plate 102 , and the third assembly surface 106 is located on the lower edge plate 105 .

[0063] When the thickness of the upper edge plate 102 or the lower edge plate 105 does not meet the strength requirement, it is necessary to further increase the thickness of the edge plate by stacking the second fiber cloth 2 .

[0064] In one embodiment, after the first layer of the second fiber cloth 2 in the upper edge plate secondary layer and / or the lower edge plate secondary layer is folded and formed into the assembly surface layer 34, each subsequent layer of the second fiber cloth 2 is folded. As shown by the path indicated by the dashed line. When the second fiber cloth 2 is folded, the subsequent layers of the second fiber cloth 2 need to be folded to increase the number of fiber cloth layers of the assembly surface layer 34 and enhance the strength of the assembly surface. Figure 5

[0065] Through the above method, each layer of fiber cloth is only folded once, but three assembly surfaces, i.e., the first assembly surface 103, the second assembly surface 104, and the third assembly surface 106, are formed at the same time, which takes into account the material properties of the fiber cloth, avoids damage to the fiber cloth, solves the existing lamination problem, improves the manufacturing efficiency, simply and efficiently forms three assembly surfaces, reduces the use of metal components in the CMC blade, and thus reduces the thermal mismatch problem between the metal assembly structure and the CMC blade.

[0066] In addition, the above method can also be designed in different positions and thicknesses according to the stress and assembly space of different assembly surfaces, thereby increasing the design flexibility of the CMC blade.

[0067] Specifically, a CMC blade manufacturing method includes the following steps.

[0068] S1. Perform initial structural design of the CMC blade, and obtain CMC blade strength distribution values under different temperature and pressure loads in the initial structural design; S2. Modify the geometric parameters of the CMC blade according to the strength distribution values, obtain a secondary structural design of the blade, and obtain CMC blade strength distribution values under different temperature and pressure loads in the secondary structural design; S3. Repeat steps S1-S2 until the final geometric parameters that meet the strength requirements are obtained; S4. Determine the number of blade layers, the number of folded layers, and the layering sequence based on the final geometric parameters; S5. Use the above blade layering method, i.e., Figure 5 the steps S51-S56 shown in the figure to layer, and obtain a layered blade; S6. Perform subsequent processing on the layered blade to obtain a formed blade.

[0069] In steps S1-S3, a simulation software is used to design and iterate the structure of the CMC blade until the geometric parameters that meet the design requirements are obtained.

[0070] In one embodiment, the geometric parameters include the assembly surface thickness, the assembly surface height, and the assembly surface fillet, which determine the number of blade layers and the number of folded layers.

[0071] Specifically, refer to Figure 4 and Figure 5 ​As shown, after calculation, the force conditions of each surface of the blade can be different, the assembly space is also different, and therefore the thickness of the assembly surface is also different.

[0072] For example, the thickness of the blade body 101 is set as H1, the thickness of the upper edge plate 102 is set as H2, the thickness of the first assembly surface 103 is set as H3, the thickness of the second assembly surface 104 is set as H4, the thickness of the lower edge plate 105 is set as H5, the thickness of the third assembly surface 106 is set as H6, and the thickness of the fourth assembly surface 107 is set as H7, and the thickness of the fifth assembly surface 108 is set as H8.

[0073] The thickness H1 of the blade body 101 is determined by the number of layers of the first fiber cloth 1, the thickness H2 of the upper edge plate 102 and the thickness H5 of the lower edge plate 105 are determined by the sum of the first fiber cloth 1 and the second fiber cloth 2, and the thickness H3, H4 and H6 of the third assembly surface 103, the fourth assembly surface 104 and the third assembly surface 106 are determined by the number of layers of the second fiber cloth 2 that are folded.

[0074] For example, if the thickness of the single-layer first fiber cloth 1 and the second fiber cloth 2 is 0.2mm, 20 layers of the first fiber cloth 1 are laid at the blade body 101, and the thickness H1 of the blade body is 4mm. The first fiber cloth 1 laid at the blade body is folded once on each side of the upper and lower sides to obtain the upper edge plate 102 and the lower edge plate 105, and in addition, 15 layers of the second fiber cloth 2 are laid at the upper edge plate 102, and the thickness H2 of the upper edge plate 102 is (20+15)·0.2, that is, 7mm.

[0075] In the 15 layers of the second fiber cloth 2, 10 layers are selected and folded on both sides to obtain the first assembly surface 103 and the second assembly surface 104, and the thickness of the first assembly surface 103 and the second assembly surface 104 is 2mm; if 8 layers are selected on one side to form the first assembly surface 103 and 12 layers are selected on the other side to form the second assembly surface 104, the thickness of the first assembly surface 103 and the second assembly surface 104 is 1.6mm and 2.4mm respectively; and if all the 15 layers are folded, the thickness of the first assembly surface 103 and the second assembly surface 104 is 3mm.

[0076] The thickness of the fourth assembly surface 107 is H7 and the thickness of the fifth assembly surface 108 is H8, which can be consistent with the thickness of the blade, i.e. the same number of layers of the first fiber cloth 1; or the layers can be lost, i.e. part of the fourth assembly surface 107 and the fifth assembly surface 108 composed of part of the first fiber cloth is cut off, so that the thickness of the fourth assembly surface 107 and the fifth assembly surface 108 is inconsistent with the thickness of the blade. For example, if the number of layers of the first fiber cloth 1 is 15 layers, the thickness of the blade is 3mm, and the designed thickness of the fourth assembly surface 107 is 2mm, 5 layers of the first fiber cloth 1 can be cut off at the position of the first assembly surface 103, so that there are only 10 layers at the position of the fourth assembly surface 107, thereby achieving the thinning process.

[0077] At the same time of laying the whole layer of fiber cloth on the upper and lower edge plates, in order to improve the interlayer tensile strength, the laid whole layer of fiber cloth can be inserted in the blade layer. As shown in Figure 4 The middle of the first fiber cloth 1 layer of the blade is increased with a whole layer of second fiber cloth 2, so that the whole layer of fiber cloth and the blade layer are alternated. The first fiber cloth 1 and the second fiber cloth 2 are alternately laid, i.e. the first fiber cloth 1 is cut and folded into the blade, and then a layer of second fiber cloth 2 is laid, so that there is a continuous, uncut second fiber cloth 2 in the middle of each layer or several layers of cut first fiber cloth 1, thereby improving the interlayer tensile strength of the upper and lower edge plates and providing higher assembly strength for the CMC turbine blade.

[0078] In an embodiment, after the completion of step S5, the outer mold is wrapped outside the outermost layer of fiber cloth to preliminarily shape the laid blade, so that the preliminarily shaped blade is better shaped in the subsequent process of step S6, such as high temperature pyrolysis.

[0079] The above method can be designed with different thicknesses at different positions according to the stress and assembly space of different assembly surfaces, and the thickness is determined by the fiber cloth laid layer by layer, thereby increasing the design flexibility of the CMC blade.

[0080] The application uses specific language to describe the embodiments of the application. As used in this application, the terms "one embodiment," "an embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. Therefore, it is emphasized and should be appreciated that a described "embodiment" or "one embodiment" or "an alternative embodiment" is not necessarily a same embodiment as previously mentioned embodiments. Additionally, the various features, structures, or characteristics of one or more embodiments of this application can be combined in any suitable manner. In order to simplify the present disclosure, expressions of the foregoing description are sometimes used to generalize the description of one or more embodiments of the application. However, such a disclosure does not imply that the application requires a greater number of features than those mentioned in the claims. In fact, an embodiment of the application has fewer features than all the features disclosed in the foregoing description of a single embodiment.

[0081] Although the present application has been disclosed in connection with the preferred embodiments shown, it should be understood that certain modifications would occur to those skilled in the art and are intended to be within the scope of the application, which is to be limited only by the claims. Accordingly, the application is not to be construed as limited to the specific examples or embodiments disclosed.

Claims

1. A method of layup of a vane for forming a CMC vane, the CMC vane comprising a vane body, an upper shroud and a lower shroud, the upper shroud and the lower shroud further comprising a plurality of mating faces for lapping with metal components, characterized in that, The method comprises the following steps: Laying a plurality of layers of first fiber cloth outside the vane inner cavity mold to form a vane body layer; When laying each layer of first fiber cloth, folding the upper side and the lower side of each layer of first fiber cloth once to form an upper edge plate layer and a lower edge plate layer, and adding a layer of second fiber cloth on each of the upper edge plate layer and / or the lower edge plate layer to form a second upper edge plate layer and / or a second lower edge plate layer; When adding each layer of second fiber cloth, the second fiber cloth of the layer is selectively folded to form an assembly surface layer; When the first fiber cloth of each layer of the vane body layer is folded to form the upper edge plate layer and the lower edge plate layer, a cut is needed, and a fiber cloth patch is used for stitching at the cut to form a stitched fiber layer; A new layer of first fiber cloth is placed on the stitched fiber layer, and the new layer of first fiber cloth and the stitched fiber layer are alternately placed.

2. The method of laying up a blade shell according to claim 1, wherein, After the first folding of the second fiber cloth in the second upper edge plate layer and / or the second lower edge plate layer and the formation of the assembly surface layer, each subsequent layer of second fiber cloth is folded.

3. A method of manufacturing a CMC vane, characterized by, The method comprises the following steps: S1. Perform initial structural design of the CMC vane, and obtain CMC vane strength distribution values under different temperature and pressure loads under the initial structural design; S2. Modify the geometric parameters of the CMC vane according to the strength distribution values, obtain a secondary structural design of the vane, and obtain CMC vane strength distribution values under different temperature and pressure loads under the secondary structural design; S3. Repeat steps S1-S2 until the final geometric parameters that meet the strength requirements are obtained; S4. Determine the number of vane layup layers, the number of folded layers, and the layup sequence based on the final geometric parameters; S5. Use the vane layup method according to any one of claims 1-2 to perform layup to obtain a layup vane; S6. Perform subsequent processing on the layup vane to obtain a formed vane.

4. The CMC vane manufacturing method of claim 3, wherein, After step S5 is completed, an outer mold is wrapped outside the outermost layer of fiber cloth to preliminarily shape the layup vane.

5. The CMC vane manufacturing method of claim 3, wherein, The geometric parameters include assembly surface thickness, assembly surface height, and assembly surface fillet.

6. The CMC vane manufacturing method of claim 3, wherein, In step S6, the subsequent processing includes a high-temperature pyrolysis shaping link. The geometric parameters include assembly surface thickness, assembly surface height, and assembly surface fillet.

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