阅读说明：本技术 一种直升机桨叶钛合金包边的处理方法 (Treatment method for titanium alloy wrapping edges of helicopter blades ) 是由 张艳苓 朱彦海 陈福龙 王耀奇 于 2021-01-04 设计创作，主要内容包括：本发明涉及一种直升机桨叶钛合金包边的处理方法,一种直升机桨叶钛合金包边的处理方法,包括以下步骤：钛合金板材喷砂；第一酸洗,将喷砂处理后的钛合金板材进行除油酸洗；涂防氧化涂料,将清洗后的钛合金板材的两面分别喷涂防氧化涂料；热成形,将涂防氧化涂料后的钛合金板材通过热成形加工成钛合金包边；除防氧化涂料,除去钛合金包边表面的防氧化涂料；碱崩,对钛合金包边进行碱崩处理；第二酸洗,对钛合金包边进行第二酸洗；阳极氧化,对钛合金包边进行阳极氧化处理；胶接,将阳极氧化后的钛合金包边和防除冰加热组件、桨叶本体分别进行胶接固化。提高了钛合金包边的精度及胶接性能。本发明应用于直升机技术领域。(The invention relates to a method for processing titanium alloy covered edges of helicopter blades, which comprises the following steps: sand blasting is carried out on the titanium alloy plate; performing first acid washing, namely performing oil removal and acid washing on the titanium alloy plate subjected to sand blasting; coating an anti-oxidation coating, namely respectively spraying the anti-oxidation coating on two surfaces of the cleaned titanium alloy plate; thermoforming, namely thermoforming the titanium alloy plate coated with the anti-oxidation coating into a titanium alloy wrapping edge; removing the anti-oxidation coating and removing the anti-oxidation coating on the surface of the titanium alloy wrapping edge; performing alkali disintegration, namely performing alkali disintegration treatment on the titanium alloy covered edge; carrying out second acid washing, namely carrying out second acid washing on the titanium alloy covered edge; anodizing, namely anodizing the titanium alloy covered edge; and (3) gluing and solidifying the anodized titanium alloy wrapping edge, the deicing heating assembly and the blade body respectively. The precision and the bonding performance of the titanium alloy wrapping edge are improved. The invention is applied to the technical field of helicopters.)

1. A method for processing titanium alloy covered edges of helicopter blades is characterized by comprising the following steps:

carrying out sand blasting on the titanium alloy plate, namely carrying out sand blasting on one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge;

performing first acid washing, namely performing oil removal and acid washing on the titanium alloy plate subjected to sand blasting;

coating an anti-oxidation coating, namely respectively spraying the anti-oxidation coating on two surfaces of the cleaned titanium alloy plate;

thermoforming, namely thermoforming the titanium alloy plate coated with the anti-oxidation coating into a titanium alloy wrapping edge;

removing the anti-oxidation coating and removing the anti-oxidation coating on the surface of the titanium alloy wrapping edge;

performing alkali disintegration, namely performing alkali disintegration treatment on the titanium alloy covered edge to remove an oxide skin;

carrying out second acid washing, namely carrying out second acid washing on the titanium alloy covered edge;

anodizing, namely anodizing the titanium alloy covered edge;

and (3) gluing and solidifying the anodized titanium alloy wrapping edge, the deicing heating assembly and the blade body respectively.

2. The method for processing the titanium alloy covered edge of the helicopter blade as claimed in claim 1, wherein in the step of blasting the titanium alloy plate, 40-120 meshes of carborundum or alumina sand is adopted to dry-spray one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge, and the dry-spray pressure is 0.2-0.8 MPa.

3. The processing method of a titanium alloy covered edge of a helicopter blade as claimed in claim 1, wherein in the step of coating the anti-oxidation coating, the two surfaces of the cleaned titanium alloy plate are respectively sprayed with T50 anti-oxidation coating.

4. The method for processing the titanium alloy covered edge of the helicopter blade according to claim 1, characterized in that in the step of thermoforming, a male die and a female die for thermoforming are loaded on a hot press for heating, when a preset temperature is reached, a titanium alloy plate is placed between the male die and the female die, the surface of the titanium alloy plate subjected to sand blasting is in contact with the male die, the surface of the titanium alloy plate not subjected to sand blasting is in contact with the female die, and the temperature and pressure are maintained for 1-20 minutes.

5. The method for processing the titanium alloy covered edge of the helicopter blade as claimed in claim 4, wherein the preset temperature is 650-850 ℃.

6. The processing method of the titanium alloy covered edge of the helicopter blade as claimed in claim 1, wherein in the step of alkali disintegration, the titanium alloy covered edge is subjected to alkali disintegration processing in a solution of 200-1000 g/L sodium hydroxide and 100-300 g/L sodium nitrite to remove oxide skin.

7. The method for processing the titanium alloy covered edge of the helicopter blade as claimed in claim 1, wherein in the second pickling step, 250-700 ml/L nitric acid with a concentration of 68% and 3-100 ml/L hydrofluoric acid with a concentration of 40% are used for pickling the titanium alloy covered edge.

8. The method for processing the titanium alloy covered edge of the helicopter blade according to claim 1, wherein in the step of anodizing, the inner surface of the titanium alloy covered edge is anodized in 50-150 ml/L sulfuric acid solution, and the anodizing voltage is 10-50V.

9. The method for processing the titanium alloy covered edge of the helicopter blade as claimed in claim 1, wherein in the step of gluing, the deicing prevention heating component is made of rubber material, and the titanium alloy covered edge and the rubber material are glued and cured by J200-1A adhesive.

10. The processing method for the titanium alloy covering edge of the helicopter blade as claimed in claim 1, wherein in the step of gluing, a SY-24C (II) adhesive is used for gluing and curing the titanium alloy covering edge and the blade body.

Technical Field

The invention relates to the technical field of helicopters, in particular to a method for processing titanium alloy wrapping edges of helicopter blades.

Background

The helicopter rotor blade mainly comprises a blade body 5 made of a composite material, an anti-icing and deicing heating assembly 4 and a covered edge 31 of the front edge, wherein the covered edge 31 is an important protection structure of the blade and is mainly used for protecting the blade body 5 made of the composite material from being impacted by air scouring and raised foreign matters such as sand dust, broken stones and the like during high-speed rotation, so that the composite material is damaged in a layered mode. At present, the blade edge covering 31 is mainly made of 0Cr18Ni9Ti stainless steel, but the stainless steel has poor corrosion resistance, low room-temperature forming precision and large bonding stress, so that the phenomena of glue opening, shedding and the like can occur in the use process of the edge covering 31, and the flight safety of the helicopter is influenced.

The titanium alloy has the advantages of low density, good corrosion resistance, high hot forming precision and the like, and can further improve the corrosion resistance and reliability of the blade edge covering 31 by replacing stainless steel with the titanium alloy, the titanium alloy edge covering 31 is generally formed by a hot bending forming method, the inner surface of the edge covering 31 after hot forming needs to be respectively glued with the deicing heating assembly 4 and the blade body 5, and the inner surface needs to be roughened before gluing in order to improve the gluing quality of the edge covering 31.

In the prior art, a common method is to perform sand blasting on the inner surface of an original titanium alloy plate or an edge covering 31, when the original titanium alloy plate is subjected to high-temperature hot press forming after sand blasting, pressure and high-temperature oxidation can generate adverse effects on the sand blasting surface, so that the bonding performance of a formed part is reduced, and as the edge covering 31 of the titanium alloy is thin in wall thickness and large in size, and the wall thickness is only 0.5-0.6 mm, deformation and internal stress are easily generated by sand blasting after forming, the precision of the edge covering 31 of the titanium alloy is poor, the bonding stress is large, the bonding performance is unstable, and the use safety of the edge covering 31 of the titanium alloy edge covering is influenced.

Therefore, the inventor provides a method for processing the titanium alloy covered edge of the helicopter blade.

Disclosure of Invention

(1) Technical problem to be solved

The embodiment of the invention provides a method for processing titanium alloy covered edges of helicopter blades, which combines sand blasting treatment of a titanium alloy plate before deformation with anodic oxidation treatment after thermal forming, and solves the problems of deformation caused by sand blasting treatment of a bonding surface after forming, reduced bonding performance after thermal forming of the sand blasting surface and the like.

(2) Technical scheme

In a first aspect, an embodiment of the present invention provides a method for processing a titanium alloy covered edge of a helicopter blade, including the following steps:

carrying out sand blasting on the titanium alloy plate, namely carrying out sand blasting on one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge;

performing first acid washing, namely performing oil removal and acid washing on the titanium alloy plate subjected to sand blasting;

coating an anti-oxidation coating, namely respectively spraying the anti-oxidation coating on two surfaces of the cleaned titanium alloy plate;

thermoforming, namely thermoforming the titanium alloy plate coated with the anti-oxidation coating into a titanium alloy wrapping edge;

removing the anti-oxidation coating and removing the anti-oxidation coating on the surface of the titanium alloy wrapping edge;

performing alkali disintegration, namely performing alkali disintegration treatment on the titanium alloy covered edge to remove an oxide skin;

carrying out second acid washing, namely carrying out second acid washing on the titanium alloy covered edge;

anodizing, namely anodizing the titanium alloy covered edge;

and (3) gluing and solidifying the anodized titanium alloy wrapping edge, the deicing heating assembly and the blade body respectively.

Further, in the step of sand blasting of the titanium alloy plate, dry spraying is carried out on one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge by adopting 40-120 meshes of carborundum or alumina sand, and the dry spraying pressure is 0.2-0.8 MPa.

Further, in the step of coating the anti-oxidation coating, the two surfaces of the cleaned titanium alloy plate are respectively sprayed with T50 anti-oxidation coating.

Further, in the step of thermoforming, a male die and a female die for thermoforming are arranged on a hot press to be heated, when the preset temperature is reached, a titanium alloy plate is placed between the male die and the female die, the surface, subjected to sand blasting, of the titanium alloy plate is in contact with the male die, the surface, not subjected to sand blasting, of the titanium alloy plate is in contact with the female die, and the temperature and the pressure are kept for 1-20 minutes.

Further, the preset temperature is 650-850 ℃.

Further, in the step of alkali disintegration, the titanium alloy covered edge is subjected to alkali disintegration treatment in a solution with 200-1000 g/L of sodium hydroxide and 100-300 g/L of sodium nitrite to remove oxide skin.

Further, in the second pickling, 250-700 ml/L nitric acid with the concentration of 68% and 3-100 ml/L hydrofluoric acid with the concentration of 40% are adopted to pickle the titanium alloy covered edge.

Further, in the step of anodizing, anodizing the inner surface of the titanium alloy covered edge in 50-150 ml/L sulfuric acid solution, wherein the anodizing voltage is 10-50V.

Further, in the step of bonding, the ice prevention and removal heating assembly is made of rubber materials, and the titanium alloy wrapping edges and the rubber materials are bonded and cured by J200-1A adhesive.

And further, in the step of gluing, a SY-24C (II) adhesive is adopted between the titanium alloy wrapping edge and the blade body for gluing and curing.

(3) Advantageous effects

In conclusion, in the method for processing the titanium alloy covered edge of the helicopter blade, the step of sand blasting the titanium alloy plate is to obtain a rough surface which is clean and has proper roughness, so that the method is beneficial to improving the bonding force of the anti-oxidation coating and the bonding force of the adhesive; the first acid washing step is to remove oil stains and other pollutants on the surface of the titanium alloy plate; the step of coating the anti-oxidation coating is to prevent the titanium alloy plate from being oxidized in the hot forming process and play a role in lubricating in the forming process; step of hot forming, namely processing the titanium alloy plate into a titanium alloy wrapping edge; the step of removing the anti-oxidation coating is to remove the anti-oxidation coating on the surface of the titanium alloy covered edge, and particularly, the anti-oxidation coating on the surface of the titanium alloy covered edge is cleaned by clear water, so that the cost is low; the step of alkali disintegration is to further clean the coating, dirt and titanium alloy oxide on the titanium alloy covered edge; the second acid washing step is to remove oxides and impurities on the titanium alloy covered edge and to influence the size and the surface roughness of the titanium alloy covered edge as little as possible; the step of anodizing is to improve an inert structure on the bonding surface of the titanium alloy covered edge and further improve the bonding performance of the titanium alloy covered edge and an anti-icing and deicing heating assembly as well as the bonding performance of the titanium alloy covered edge and a blade body made of a composite material; the step of bonding is used for respectively performing bonding solidification on the titanium alloy edge after anodic oxidation, the deicing heating assembly and the blade body.

According to the method for processing the titanium alloy wrapping edge of the helicopter blade, the problems of deformation caused by sand blasting treatment on the bonding surface after forming, bonding performance reduction after hot forming on the sand blasting surface and the like are solved by combining sand blasting treatment on the titanium alloy plate before deformation with anodic oxidation treatment after hot forming, so that the manufacturing precision of the titanium alloy wrapping edge and the bonding performance between the titanium alloy wrapping edge and an anti-icing heating assembly and between the titanium alloy wrapping edge and a blade body made of a composite material are further improved, the molding precision of the titanium alloy wrapping edge on the front edge of the helicopter blade can be well ensured, the bonding strength and durability of the titanium alloy wrapping edge and the anti-icing heating assembly and between the titanium alloy wrapping edge and the blade body are improved, and the use safety of the titanium alloy wrapping edge is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a partial cross-sectional view of a prior art helicopter rotor blade.

FIG. 2 is a schematic diagram showing the relationship between a male die, a female die and a titanium alloy sheet in the step of thermoforming according to the embodiment of the present invention.

Fig. 3 is a schematic structural view of a titanium alloy covered edge according to an embodiment of the invention.

In the figure:

1-male die; 2-a female die; 3-titanium alloy edge covering; 31-edge wrapping; 4-an anti-icing heating component; 5-blade body.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the invention and are not intended to limit the scope of the invention, i.e., the invention is not limited to the embodiments described, but covers any modifications, alterations, and improvements in the parts, components, and connections without departing from the spirit of the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 1 to 3, the titanium alloy covered edge 3 of the present embodiment and the covered edge 31 of the prior art have the same shape and structure, and therefore, for convenience of illustration, the covered edge 31 in fig. 1 may represent the titanium alloy covered edge 3 of the present embodiment.

A method for processing titanium alloy covered edges of helicopter blades comprises the following steps:

carrying out sand blasting on the titanium alloy plate, namely carrying out sand blasting on one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge 3;

performing first acid washing, namely performing oil removal and acid washing on the titanium alloy plate subjected to sand blasting;

coating an anti-oxidation coating, namely respectively spraying the anti-oxidation coating on two surfaces of the cleaned titanium alloy plate;

thermoforming, namely thermoforming the titanium alloy plate coated with the anti-oxidation coating into a titanium alloy covered edge 3;

removing the anti-oxidation coating and removing the anti-oxidation coating on the surface of the titanium alloy wrapping 3;

performing alkali disintegration, namely performing alkali disintegration treatment on the titanium alloy edge covering 3 to remove oxide skin;

performing second pickling, namely performing second pickling on the titanium alloy wrapping 3;

anodizing, namely anodizing the titanium alloy covered edge 3;

and (3) performing adhesive bonding, namely respectively performing adhesive bonding and curing on the anodized titanium alloy edge 3, the deicing heating assembly 4 and the blade body 5.

In the method for treating the titanium alloy covered edge of the helicopter blade, the step of sand blasting the titanium alloy plate is to obtain a rough surface which is clean and has proper roughness, so that the bonding force of the anti-oxidation coating and the bonding force of the adhesive are improved; the first acid washing step is to remove oil stains and other pollutants on the surface of the titanium alloy plate; the step of coating the anti-oxidation coating is to prevent the titanium alloy plate from being oxidized in the hot forming process and play a role in lubricating in the forming process; step hot forming is used for processing the titanium alloy plate into a titanium alloy covered edge 3; the step of removing the anti-oxidation coating is to remove the anti-oxidation coating and impurities on the surface of the titanium alloy covered edge 3, and particularly, the anti-oxidation coating on the surface of the titanium alloy covered edge 3 is cleaned by clear water, so that the cost is low; the step of alkali disintegration is to further clean the coating, dirt and titanium alloy oxide on the titanium alloy covered edge 3; the second acid cleaning step is to remove oxides on the titanium alloy covered edge 3 and to influence the size and the surface roughness of the titanium alloy covered edge 3 as little as possible; the step of anodizing is to improve an inert structure on the adhesive surface of the titanium alloy covered edge 3 and further improve the adhesive property of the titanium alloy covered edge 3 and the deicing heating component 4 and the adhesive property of the titanium alloy covered edge 3 and the blade body 5 made of the composite material; the step of gluing is used for respectively gluing and curing the anodized titanium alloy edge 3, the deicing heating assembly 4 and the blade body 5.

According to the method for processing the titanium alloy covered edge of the helicopter blade, the problems of deformation caused by sand blasting treatment on the bonding surface after forming, bonding performance reduction after hot forming on the sand blasting surface and the like are solved by combining sand blasting treatment on the titanium alloy plate before deformation with anodic oxidation treatment after hot forming, so that the manufacturing precision of the titanium alloy covered edge 3 is further improved, the bonding performance between the titanium alloy covered edge 3 and the anti-icing heating assembly 4 and between the titanium alloy covered edge 3 and the blade body 5 made of the composite material is improved, the molding precision of the titanium alloy covered edge 3 on the front edge of the helicopter blade can be well guaranteed, the bonding strength and durability of the titanium alloy covered edge 3 and the anti-icing heating assembly 4 and between the titanium alloy covered edge 3 and the blade body 5 are improved, and the use safety of the titanium alloy covered edge 3 is improved.

In the embodiment, as a further improvement of the technical scheme, in the step of blasting the titanium alloy plate, one surface of the titanium alloy plate for manufacturing the titanium alloy covered edge 3 is subjected to dry spraying by using 40-120-mesh carborundum or alumina sand, and the dry spraying pressure is 0.2-0.8 MPa. Specifically, one side of a TC4 titanium alloy plate with the thickness of 1300 x 300 x 0.5mm is subjected to sand blasting, alumina sand with the sand grain number of 60 is adopted, dry blasting is carried out, the pressure is 0.2Mpa, and the roughness of the surface of the titanium alloy plate obtained after sand blasting is 2.83 microns.

In this embodiment, as a further improvement of the above technical solution, in the step of coating the anti-oxidation coating, T50 anti-oxidation coatings are respectively sprayed on two surfaces of the cleaned titanium alloy plate.

In the embodiment, as a further improvement of the technical scheme, in the step of thermoforming, the male die 1 and the female die 2 for thermoforming are arranged on a hot press for heating, when a preset temperature is reached, a titanium alloy plate is placed between the male die 1 and the female die 2, the surface, subjected to sand blasting, of the titanium alloy plate is in contact with the male die 1, the surface, not subjected to sand blasting, of the titanium alloy plate is in contact with the female die 2, and the heat preservation and pressure maintaining are carried out for 1-20 minutes. In this embodiment, as a further improvement of the above technical solution, the preset temperature is 650 to 850 ℃. Specifically, a hemming hot forming die is arranged on a hot press to be heated, when the temperature is raised to 700 ℃, a titanium alloy plate is arranged, one surface of the titanium alloy plate subjected to sand blasting is in contact with a male die 1, the surface of the titanium alloy plate not subjected to sand blasting is in contact with a female die 2, the die is closed, the hot forming is carried out, and the heat preservation and pressure maintaining are carried out for 15 minutes.

In the embodiment, as a further improvement of the technical scheme, in the step of alkali disintegration, the titanium alloy covered edge 3 is subjected to alkali disintegration treatment in a solution of 200-1000 g/L of sodium hydroxide and 100-300 g/L of sodium nitrite to remove oxide skin. Specifically, the titanium alloy edge covering 3 is subjected to alkali disintegration treatment in a solution with 200-1000 g/L of sodium hydroxide and 100-300 g/L of sodium nitrite to remove oxide skin, so that the coating, dirt and titanium alloy oxide are further cleaned.

In the embodiment, as a further improvement of the technical scheme, in the second pickling in the step, 250-700 ml/L of nitric acid with a concentration of 68% and 3-100 ml/L of hydrofluoric acid with a concentration of 40% are used for pickling the titanium alloy covered edge 3. Specifically, the titanium alloy covered edge 3 is pickled by using a solution of 300ml/L nitric acid (68%) and 40ml/L hydrofluoric acid (40%), so as to remove oxides and influence the size and the surface roughness of the titanium alloy covered edge 3 as little as possible.

In the embodiment, as a further improvement of the technical scheme, in the step of anodizing, anodizing the inner surface of the titanium alloy covered edge 3 in 50-150 ml/L sulfuric acid solution, and the anodizing voltage is 10-50V. Specifically, the inner surface of the titanium alloy edge-covering 3 is subjected to anodic oxidation treatment in 100ml/L sulfuric acid solution, the anodic oxidation voltage is 20V, and the purpose is to improve the inert structure of the adhesive surface of the titanium alloy edge-covering 3 and further improve the adhesive property of parts.

In the embodiment, as a further improvement of the technical scheme, in the step of bonding, the ice prevention and removal heating assembly 4 is made of a rubber material, and the titanium alloy wrapping 3 and the rubber material are bonded and cured by a J200-1A adhesive.

In the embodiment, as a further improvement of the technical scheme, in the step of bonding, a SY-24C (II) adhesive is used between the titanium alloy wrapping 3 and the blade body 5 for bonding and curing.

The above description is only an example of the present application and is not limited to the present application. Various modifications and alterations to this application will become apparent to those skilled in the art without departing from the scope of this invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.