Fixture and clamping method for aero-engine blade heat treatment

Abstract

The invention relates to the field of aero-engine blade heat treatment clamps, in particular to a clamp for aero-engine blade heat treatment and a clamping method, and the clamp is formed by circuitously bending a stainless steel wire to form a first rod body and a second rod body; the first rod body and the second rod body are arranged in parallel at an interval; the first rod body and the second rod body are respectively sleeved with a plurality of ceramic rings in a sliding mode. The method comprises the following steps of S1, inserting a blade to be subjected to heat treatment into a gap between the first rod body and the second rod body, and S2, selecting a proper number of ceramic rings to be in contact with the blade basin side and the blade back side of the blade to support the blade. When the blade is clamped, a proper number of ceramic rings are selected to be in contact with the blade basin side and the blade back side of the blade, the blade is supported, gaps exist between the adjacent ceramic rings, the temperature uniformity of the blade in the heat treatment process is improved, and the structure transformation consistency and uniformity of the blade in the heat treatment process are promoted.

Description

Technical Field

[0001] The invention relates to the field of heat treatment fixtures for aircraft engine blades, and in particular to a fixture and a clamping method for heat treatment of aircraft engine blades. Background Art

[0002] During the high-temperature heat treatment process, the contact area between aircraft engine blades and the stainless steel fixture is large, and during the heat treatment, especially during the high-temperature heat treatment process, the stainless steel fixture and the blade material will stick together and atomic diffusion will occur. This is a major technical difficulty that needs to be paid attention to and solved during the heat treatment of aircraft engine blades, especially the heat treatment of precision forged blades.

[0003] During the heat treatment of aircraft engine blades, the fixture can promote the uniformity of heat treatment of blades and simplify the clamping process to a certain extent, thereby improving labor productivity. However, how to design a fixture that can avoid diffusion and sticking between the blades and the metal fixture becomes particularly critical. Especially for precision forged blades, this atomic diffusion will seriously affect the organizational state of the contact area between the blade and the fixture, thereby interfering with the process performance of subsequent special treatments. Such as: aluminum infiltration, etc. This diffusion may further affect the physical and chemical properties of the blades, such as reducing the comprehensive mechanical properties, corrosion resistance, ablation resistance and other key properties of the blades, and ultimately destroying the service status of the aircraft engine blades.

[0004] The fixture in the prior art, such as the patent application with publication number CN115505689A, discloses a combined fixture and a clamping method for heat treatment of precision forged blades of aircraft engines. The blade rack of the combined fixture for clamping the blades includes a plurality of parallel ceramic tubes arranged at intervals in the same plane, and the plurality of ceramic tubes are rotatably connected to the blade rack. When clamping the blade to be processed, the blade to be processed is inserted into the gap between two adjacent ceramic tubes.

[0005] However, the combined clamp disclosed in the above CN115505689A has the following problems:

[0006] (1) The contact area between the entire ceramic rod and the blade to be treated is too large, resulting in uneven temperature of the blade during the heat treatment process, which in turn affects the consistency and uniformity of the microstructure transformation during the heat treatment of the blade.

[0007] (2) During the heat treatment process, since the ceramic tube and the blade rack are rotatably connected, that is, the interval between two adjacent ceramic tubes is fixed, the blades expand due to heat during the heat treatment and are likely to squeeze the ceramic tube. If the ceramic tube is damaged, the entire tube needs to be replaced, resulting in waste. Summary of the invention

[0008] The main purpose of the present invention is to provide a fixture and a clamping method for heat treatment of aircraft engine blades, aiming to solve the above technical problems.

[0009] To achieve the above-mentioned purpose, on the one hand, the present invention proposes a fixture for heat treatment of aircraft engine blades, which uses stainless steel wire to bend in a circuitous manner to form a first rod body and a second rod body; the first rod body and the second rod body are arranged in parallel and spaced apart; and a plurality of ceramic rings are slidably sleeved on the first rod body and the second rod body respectively.

[0010] Preferably, the material of the ceramic ring is Si 3 N 4 ceramics.

[0011] Preferably, the ceramic ring is made of BN ceramic.

[0012] Preferably, the length of the ceramic ring is 3 to 6 mm.

[0013] Preferably, the diameter of the stainless steel wire material is φ3 mm, and the inner hole diameter of the ceramic ring is φ3.5 mm.

[0014] Preferably, one end of the second rod body away from the first hanging portion is bent to form a hook body and is used to buckle on the first rod body.

[0015] Preferably, the connection portion between the first rod body and the second rod body is bent downward to form a first hanging portion; and one end of the first rod body away from the first hanging portion is bent downward to form a second hanging portion.

[0016] On the other hand, the present invention also provides a clamping method for heat treatment of aircraft engine blades, using the above-mentioned fixture, comprising the following steps:

[0017] S1. Insert the blade to be heat treated into the gap between the first rod and the second rod.

[0018] S2. Slide ceramic rings left and right on the first rod and the second rod, and select a suitable number of ceramic rings to contact the blade basin side and the blade back side of the blade to form support for the blade.

[0019] Preferably, in step S2, three ceramic rings are used to form a three-point support structure for the blade.

[0020] Preferably, the method of forming a three-point support for the blade is: when two ceramic rings are used to support the blade basin side, one ceramic ring is used to support the blade back side; when one ceramic ring is used to support the blade basin side, two ceramic rings are used to support the blade back side.

[0021] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0022] (1) In the present invention, when clamping the blades to be heat treated, ceramics are used to support the blades, so that the stainless steel wire material is separated from the blades, which can completely avoid direct contact between the blades and the first rod body and the second rod body, completely eliminate sticking and diffusion behaviors, and effectively improve the material consistency of the blades. In addition, compared with the clamps in the prior art, when clamping the blades, a suitable number of ceramic rings are selected to contact the blade basin side and the blade back side to form a support for the blade, and there are gaps between adjacent ceramic rings, which improves the temperature uniformity of the blades during the heat treatment process and promotes the consistency and uniformity of the structural transformation of the blades during the heat treatment process. It effectively overcomes the problem of excessively large contact area between the entire ceramic rod and the blade to be treated in the prior art.

[0023] (2) In the present invention, three ceramic rings form a three-point support structure for the blade. Specifically, when two ceramic rings are used to support the blade basin side, one ceramic ring is used to support the blade back side; when one ceramic ring is used to support the blade basin side, two ceramic rings are used to support the blade back side. The three-point support method reduces the number of ceramic rings in contact with the blade while ensuring the reliability of clamping, thereby improving the temperature uniformity of the blade during the heat treatment process.

[0024] (3) By adopting the fixture and clamping method provided by the present invention, the heat treatment process performance of aircraft engine blades and the sticking and diffusion problems after heat treatment are significantly improved, and the process adaptability of the blades after heat treatment to subsequent treatment is improved, thereby obtaining aircraft engine blades that better meet the design requirements. Finally, the comprehensive mechanical properties of the blades after heat treatment are significantly improved, ensuring the delivery quality of aircraft engine blades.

[0025] (4) The angle provided by the present invention is composed of a stainless steel wire and a plurality of ceramic rings, which has a simple structure and low manufacturing cost.

[0026] (5) Since the angle is made of stainless steel wire, when the blade expands due to heat treatment, the stainless steel wire has a certain elasticity to give way, which can prevent the ceramic ring from being squeezed and broken. In addition, even if one or two ceramic rings are damaged, it will not affect the use of the entire fixture. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0028] Figure 1 A schematic diagram of a fixture for heat treatment of aero-engine blades provided by the present invention;

[0029] Figure 2 It is an enlarged view of the second rod body in the present invention being bent to form a hook body and buckled on the first rod body.

[0030] Description of the accompanying drawings: 1. first rod body; 2. second rod body; 3. first hanging part; 4. second hanging part; 5. ceramic ring; 6. hook body. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] Combination Figure 1 to Figure 2 As shown, on the one hand, this embodiment provides a fixture for heat treatment of aircraft engine blades, which uses stainless steel wire to bend in a circuitous manner to form a first rod body 1 and a second rod body 2; the first rod body 1 and the second rod body 2 are arranged in parallel and spaced apart; and a plurality of ceramic rings 5 ​​are slidably sleeved on the first rod body 1 and the second rod body 2, respectively.

[0035] In this embodiment, the number of ceramic rings 5 ​​used on each rod body is sufficient to ensure that the fixture does not contact the blade after clamping the blade. However, under the condition of ensuring no contact, each rod body should not use too many ceramic rings 5 ​​to prevent excessive ceramic rings 5 ​​from reducing the uniformity of heating of the blade and thus affecting the microstructure and performance of the blade after heat treatment. The number of ceramic rings 5 ​​used is related to the number of blades clamped by the fixture, and will not be repeated here.

[0036] In this embodiment, the material of the ceramic ring 5 is S i 3N 4 Ceramics. Silicon nitride has good chemical stability, good heat resistance, thermal stability, thermal conductivity, and high-temperature dielectric strength. It is an ideal heat dissipation material and high-temperature insulation material. In addition, the material of the ceramic ring 5 can also be BN ceramic. Boron nitride has better thermal stability and a lower dielectric constant than silicon nitride ceramics. It is one of the few compounds whose decomposition temperature can reach 3000°C. Therefore, the ceramic ring 5 made of silicon nitride and boron nitride ceramic materials can not only eliminate the diffusion and adhesion problems between the blades and the first rod body 1 and the second rod body 2, but also promote the process performance of the blade heat treatment and the consistency and uniformity of the heat treatment effect.

[0037] In this embodiment, in order to reduce the contact area between the ceramic ring 5 and the blades, the length of the ceramic ring 5 is designed to be 3-6 mm.

[0038] In this embodiment, the diameter of the stainless steel wire material is φ3mm, and the inner diameter of the ceramic ring 5 is φ3.5mm. The ceramic ring 5 forms a clearance fit with the first rod 1 and the second rod 2, which facilitates sliding the ceramic ring 5 on the first rod 1 and the second rod 2 when clamping the blade.

[0039] Combination Figure 1 to Figure 2 As shown, one end of the second rod 2 away from the first hanging portion 3 is bent to form a hook 6 and is used to buckle on the first rod 1. By providing the hook 6, after the blade to be heat-treated is inserted into the structure between the first rod 1 and the second rod 2, the hook 6 is buckled on the first rod 1 to prevent the blade from sliding off.

[0040] Combination Figure 1 , Figure 2 As shown, the connection part between the first rod body 1 and the second rod body 2 is bent downward to form a first hanging part 3; the end of the first rod body 1 away from the first hanging part 3 is bent downward to form a second hanging part 4. When performing heat treatment, the first hanging part 3 and the second hanging part 4 are hung on the hanger of the heat treatment equipment.

[0041] In this embodiment, when the ceramic ring 5 is damaged, the ceramic ring 5 can be installed on the first rod body and the second rod body 2 in sequence from the second hanging portion 4, which is convenient for maintenance of the clamp.

[0042] On the other hand, this embodiment also provides a clamping method for heat treatment of aircraft engine blades, using the above-mentioned fixture, including the following steps:

[0043] S1, insert the blade to be heat treated into the gap between the first rod body 1 and the second rod body 2,

[0044] S2. Slide the ceramic rings 5 ​​left and right on the first rod body 1 and the second rod body 2, and select a suitable number of ceramic rings 5 ​​to contact the blade basin side and the blade back side of the blade to form support for the blade.

[0045] In step S2, three ceramic rings 5 ​​are used to form a three-point support structure for the blade. Specifically, the method of forming the three-point support for the blade is: when two ceramic rings 5 ​​are used to support the blade basin side of the blade, one ceramic ring 5 is used to support the blade back side of the blade; when one ceramic ring 5 is used to support the blade basin side of the blade, two ceramic rings 5 ​​are used to support the blade back side of the blade.

[0046] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A fixture for heat treatment of aircraft engine blades, characterized in that: A first rod body (1) and a second rod body (2) are formed by bending stainless steel wire in a circuitous manner; the first rod body (1) and the second rod body (2) are arranged in parallel and spaced apart; and a plurality of ceramic rings (5) are slidably sleeved on the first rod body (1) and the second rod body (2), respectively.

2. A fixture for heat treatment of aircraft engine blades according to claim 1, characterized in that: The material of the ceramic ring (5) is Si3N4 ceramic.

3. A fixture for heat treatment of aircraft engine blades according to claim 1, characterized in that: The material of the ceramic ring (5) is BN ceramic.

4. A fixture for heat treatment of aircraft engine blades according to claim 1, characterized in that: The length of the ceramic ring (5) is 3 to 6 mm.

5. The fixture for heat treatment of aircraft engine blades according to claim 1, characterized in that: The diameter of the stainless steel wire material is φ3 mm, and the inner hole diameter of the ceramic ring (5) is φ3.5 mm.

6. A fixture for heat treatment of aircraft engine blades as claimed in claim 1, characterized in that: One end of the second rod body (2) away from the first hanging portion (3) is bent to form a hook body (6) and is used to buckle onto the first rod body (1).

7. A fixture for heat treatment of aircraft engine blades as claimed in claim 1, characterized in that: The connection portion between the first rod body (1) and the second rod body (2) is bent downward to form a first hanging portion (3); and one end of the first rod body (1) away from the first hanging portion (3) is bent downward to form a second hanging portion (4).

8. A clamping method for heat treatment of aircraft engine blades, characterized in that: The clamp according to any one of claims 1 to 7 is used, comprising the following steps: S1. inserting the blade to be heat treated into the gap between the first rod (1) and the second rod (2), S2. Slide the ceramic rings (5) left and right on the first rod (1) and the second rod (2), and select a suitable number of ceramic rings (5) to contact the blade base side and the blade back side of the blade to form support for the blade.

9. A clamping method for heat treatment of aircraft engine blades according to claim 8, characterized in that: In step S2, three ceramic rings (5) are used to form a three-point support structure for the blade.

10. A clamping method for heat treatment of aircraft engine blades according to claim 9, characterized in that: The method of forming a three-point support for the blade is: When two ceramic rings (5) are used to support the blade base side of the blade, one ceramic ring (5) is used to support the blade back side of the blade; When one ceramic ring (5) is used to support the blade base side of the blade, two ceramic rings (5) are used to support the blade back side of the blade.

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