CN113263250B

CN113263250B - Composite manufacturing method of metal reinforced edge of aircraft engine fan blade

Info

Publication number: CN113263250B
Application number: CN202110426921.4A
Authority: CN
Inventors: 李细锋; 雷奕文; 陈军; 熊炜; 李铭
Original assignee: Shanghai Mold Technology Research Institute Co ltd; Shanghai Jiaotong University
Current assignee: Shanghai Mold Technology Research Institute Co ltd; Shanghai Jiaotong University
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2022-07-19
Anticipated expiration: 2041-04-20
Also published as: CN113263250A

Abstract

The invention relates to a composite manufacturing method of a metal reinforcing edge of a fan blade of an aero-engine, which comprises the steps of determining a geometric shape model of the metal reinforcing edge according to the shape of the fan blade, extending two ends of the geometric shape model, dividing the extended geometric shape model into a first prefabricated part model and a second prefabricated part model, and obtaining a first prefabricated part and a second prefabricated part; extending two ends of the fan blade shape to obtain a core mold model, dividing the core mold model into a plurality of block models, and manufacturing a block piece and a core mold; attaching the first prefabricated member and the second prefabricated member to two sides of a core mold, and fixing the core mold, the first prefabricated member and the second prefabricated member through pins to form an integral structure; placing the integral structure into a vacuum diffusion welding furnace for diffusion welding; and cutting off the extension part with the pin at two ends of the welded integral structure. Compared with the prior art, the invention has the advantages of improving the material utilization rate, shortening the processing period, greatly reducing the difficulty of cutting processing and the like.

Description

Composite manufacturing method of metal reinforcing edge of aircraft engine fan blade

Technical Field

The invention relates to the field of manufacturing of thin-wall deep-cavity reinforcing edges, in particular to a composite manufacturing method of a metal reinforcing edge of a fan blade of an aero-engine.

Background

The carbon fiber composite fan blade has the advantages of light weight, low noise, strong flutter resistance and the like, and is the mainstream choice of commercial aircraft engines. However, the impact resistance, compression resistance, lightning stroke resistance and other capabilities of the front edge part of the composite material blade are still insufficient compared with those of a metal blade, and the overall performance of the composite material blade can be obviously improved by adding the titanium alloy wrapping edge on the front edge of the composite material blade.

In order to adapt to the shape of the front edge of the composite fan blade, the titanium alloy reinforcing edge is often provided with a complex deep-cavity thin-wall special-shaped structure. If the whole reinforcing edge is machined by a cutting method, the material utilization rate is low, the machining time is long, and a cutter with a small diameter is easy to lose stability in the process of machining a deep cavity structure, so that the rejection rate is high.

For example, the invention patent with the publication number of CN109483183B discloses a method for manufacturing a metal reinforcing edge of a composite fan blade of an aeroengine. Firstly, cutting and processing two prefabricated parts, then directly welding two sides of the prefabricated parts, welding two ends of the prefabricated parts through sealing parts to obtain a hollow structure, arranging a core mold which is only used as a support in an inner cavity formed by the prefabricated parts, and then carrying out integral welding reinforcement through a high-temperature pressure maintaining device; and finally, taking down the sealing parts at the two ends, cutting off one unnecessary side, and taking out the core mold to obtain the metal reinforcing side. However, this method has the following disadvantages: 1. the steps are tedious and require primary welding for the first time and subsequent welding reinforcement. Meanwhile, the prefabricated member needs to be welded into a sealing structure through argon arc welding, the sealing structure comprises two prefabricated members, a core mold, two sealing elements and the like, and the core mold, the prefabricated members and the sealing elements are made of different materials, so that argon arc welding is difficult. 2. The welding reinforcement is carried out through the vent pipe and the high-temperature pressure maintaining device of the sealing element, the welding reinforcement is difficult to realize basically, and the quality of a connecting interface cannot be guaranteed. 3. It cannot be used for manufacturing metal reinforcing edges with large length and deep thin-wall cavities.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a composite manufacturing method of a metal reinforced edge of an aircraft engine fan blade.

The purpose of the invention can be realized by the following technical scheme:

a composite manufacturing method of a metal reinforcing edge of an aircraft engine fan blade is characterized in that the metal reinforcing edge is of a special-shaped metal thin-wall structure with a narrow deep cavity, and the composite manufacturing method comprises the following steps:

determining a geometric shape model of the metal reinforcing edge according to the shape of the fan blade, extending two ends of the geometric shape model, and dividing the extended geometric shape model into a first prefabricated part model and a second prefabricated part model;

cutting a material plate according to the first prefabricated part model and the second prefabricated part model to obtain a blank piece, and carrying out hot pressing on the blank piece to obtain a first prefabricated part and a second prefabricated part;

extending two ends of the fan blade shape to obtain a core mold model, and dividing the core mold model into a plurality of block models;

manufacturing a blocking piece according to the blocking model, and then splicing the blocking piece to obtain a core mold;

attaching the first prefabricated member and the second prefabricated member to two sides of a core mold, and fixing the core mold, the first prefabricated member and the second prefabricated member through pins to form an integral structure;

placing the integral structure into a vacuum diffusion welding furnace for diffusion welding;

and cutting off the extending part with the pins at two ends of the welded integral structure, and taking out the core mold to obtain the metal reinforcing edge.

Furthermore, the blocking pieces of the core mould are connected through a chimeric structure.

Further, a solder resist is applied to each of the outer layers of the blocks of the core mold.

And the shape of the inner cavity of the diffusion connection module is consistent with the outer surface profile of the metal reinforcing edge after the two ends of the metal reinforcing edge extend, and the integral structure is placed into the inner cavity of the diffusion connection module and then placed into a vacuum diffusion welding furnace for diffusion welding.

Further, the core mold has at least three pieces of the divided pieces.

Further, the partition of the core mold is a bent portion, a portion of which the circumferential dimension changes, or a set length portion of the fan blade shape.

Further, the lengths of the first preform and the second preform are less than or equal to the length of the core mold.

Further, the core mold is made of heat-resistant stainless steel or high-temperature alloy.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention simplifies the manufacturing process of the metal reinforcing edge of the fan blade, adopts a composite method of thermoplastic processing and diffusion welding, can obviously improve the material utilization rate, shorten the processing period, greatly reduce the difficulty of cutting processing, and has obvious cost and efficiency advantages.

2. According to the invention, the two prefabricated parts and the partitioned core mold form an integral structure, and the integral structure can be directly placed into a vacuum diffusion welding furnace mature in the prior art for diffusion welding, so that the two prefabricated parts form the integral structure, a heating and pressurizing device is not required to be additionally arranged, only one welding procedure is required, the operation is convenient, and the processing effect is good.

3. The integral structure can be arranged in a diffusion connection die and then placed in a vacuum diffusion welding furnace, so that the forming precision of the outer surface of the metal reinforcing edge is improved.

4. The core mold is of a structure of a partitioning piece and is connected with the prefabricated piece through a pin, after welding is completed, the core mold can be conveniently taken out only by cutting redundant extension parts on two sides of the integral structure, a finished product of the metal reinforcing edge is obtained, and production efficiency is high. The blocking pieces can be directly made into fan blade shapes and are mutually embedded and connected, the fan blade shape cutting device is suitable for metal reinforcing edges with large length, cutting processing only relates to the blocking pieces at two ends, the blocking pieces in the middle can be repeatedly used, and the material utilization rate is high.

5. The core mold is made of heat-resistant stainless steel or high-temperature alloy, so that deformation in the diffusion connection process is avoided, and the forming precision of the inner cavity of the metal reinforcing edge is ensured.

Drawings

FIG. 1 is a view of the construction of a complex narrow deep cavity profiled thin wall of the metal reinforcing rim of this example.

FIG. 2 is a schematic representation of the shape of the preform of this example.

FIG. 3 is a schematic of the preform thermoforming process.

Fig. 4 is a schematic structural view of the core mold.

FIG. 5 is a schematic view of the overall structure of the preform and core die assembly.

Fig. 6 is a schematic view of the structure of the integrated structure in the diffusion bonding mold.

Reference numerals: 1. metal reinforcing edge, 11, inner cavity, 2, first prefabricated part, 3, second prefabricated part, 4, 41, blocking part, 5, diffusion bonding mould.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

In order to ensure the aerodynamic performance, the composite material fan blade of the aircraft engine generally has a complex streamline shape, so as shown in fig. 1, the metal reinforcing edge 1 of the fan blade also needs to have a complex space geometry and is generally in a narrow deep-cavity special-shaped thin-wall structure. The fan blades of the composite material are tightly connected with the inner cavity 11 of the metal reinforcing edge 1 in a gluing mode and the like. The process of manufacturing the metal reinforcing flange 1 according to the present invention will be described in detail.

Firstly, determining a geometric model of the metal reinforcing side 1 according to the shape of the adaptive fan blade, then extending two ends of the geometric model, and dividing the extended geometric model into a first prefabricated member 2 model and a second prefabricated member 3 model. Meanwhile, the core mold model is obtained by extending both ends of the fan blade shape, and then the core mold model is divided into a plurality of block models. The block models have a jogged structure between them, and the segment is generally selected at the bend of the shape, the change of the circumferential dimension or the set length. The number of the blocks is generally equal to or greater than three, and three are preferred in the embodiment. Pin holes are arranged at two ends of the core model. This step may employ, but is not limited to, computer-aided CAD design.

And secondly, cutting a material plate according to the model of the first prefabricated part 2 and the model of the second prefabricated part 3 to obtain a first blank part and a second blank part, and performing hot pressing on the blank parts to obtain the first prefabricated part 2 and the second prefabricated part 3, wherein the shape of the blank parts is as close to that of the prefabricated parts as possible on the premise of easy forming. Then, hot press forming is performed through a mold, and finally, a first preform 2 and a second preform 3 are obtained, as shown in fig. 2 and 3.

Third, as shown in fig. 4, the block pieces 4 are manufactured according to the block model, and then the block pieces 41 are assembled to obtain the core mold 4. The core mold 4 is made of heat-resistant stainless steel or high-temperature alloy, and can prevent deformation in subsequent processing. And meanwhile, the outer layer of each block piece 41 is coated with solder resist, so that the block pieces are prevented from being welded with the prefabricated member.

And fourthly, as shown in fig. 5, attaching the first preform 2 and the second preform 3 to both sides of the core mold 4, and fixing the core mold 4 and the first preform 2 and the second preform 3 by pins to form an integral structure. The first preform and the second preform generally have a length less than or equal to the length of the core mold, which in this embodiment is the same.

And fifthly, placing the integral structure into an existing vacuum diffusion welding furnace for diffusion welding. The core mold 4 not only supports the first preform 2 and the second preform 3, but also shapes both the preforms and ensures the accuracy and quality of the inner surfaces thereof.

And sixthly, cutting off the extending part with the pin at the two ends of the integral structure. After the diffusion bonding is completed, the entire structure is taken out, the extending portions at both ends are cut off, the core mold 4 is taken out, and the metal reinforcing flange 11 is finally obtained. The cutting-off is not limited, and wire cutting is preferably used.

In another embodiment, as shown in fig. 6, a diffusion bonding mold 5 may be designed during the manufacturing process, and the mold has a top and bottom mold structure, and the top and bottom molds form a cavity shape after being closed. The shape of the inner cavity is consistent with the outline of the outer surface of the metal reinforcing edge 1 after the two ends extend. The integral structure formed by splicing the prefabricated member and the core mold 4 is placed into an inner cavity of the diffusion connection module and then placed into a vacuum diffusion welding furnace for diffusion welding. The diffusion bonding mold 5 applies pressure to the first preform 2 and the second preform 3 to complete the diffusion bonding process, and shapes the two preforms and ensures the accuracy and quality of the outer surfaces thereof.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the prior art according to the concepts of the present invention should be within the scope of protection determined by the claims.

Claims

1. A composite manufacturing method of a metal reinforcing edge of an aircraft engine fan blade is characterized by comprising the following steps:

manufacturing a partitioning piece according to the partitioning model, and then splicing the partitioning piece to obtain a core mold; the blocking pieces of the core mold are connected through an embedded structure; the partition of the core mold is a fan blade-shaped bending part, a circumferential size change part or a set length part;

placing the integral structure into a vacuum diffusion welding furnace for diffusion welding; the integral structure is placed into the inner cavity of the diffusion connection mould and then placed into a vacuum diffusion welding furnace for diffusion welding;

2. The composite manufacturing method for the metal reinforcing edge of the fan blade of the aircraft engine as defined in claim 1, wherein a solder resist is coated on the outer layer of each block of the core mold.

3. The composite manufacturing method for the metal reinforcing edge of the fan blade of the aero-engine as claimed in claim 1, wherein the number of the core mold divided pieces is at least three.

4. The composite manufacturing method for the metal reinforcing edge of the fan blade of the aircraft engine as claimed in claim 1, wherein the lengths of the first prefabricated member and the second prefabricated member are less than or equal to the length of the core mold.

5. The composite manufacturing method for the metal reinforcing edge of the fan blade of the aircraft engine as defined in claim 1, wherein the core mold is made of high-temperature alloy.