CN115847886A - Method and device for repairing damage of thermoplastic composite material - Google Patents

Abstract

The invention discloses a repair method and a repair device for thermoplastic composite material damage, through repair steps such as determining the damage situation, selecting tooling, selecting demoulding materials, heating repair, inspection and repair, and supplemented by two customized according to the shape of the thermoplastic composite material. The heating plate is clamped on both sides of the area to be repaired by two heating plates, and can reach the temperature of the corresponding melting material, which can make the resin matrix of the thermoplastic composite material have a certain flow, and under the action of repair pressure, cracks in the composite material , delamination and other defects are filled, and then the internal damage of the thermoplastic composite is repaired, the mechanical properties of the thermoplastic composite are restored to the greatest extent, the application ability of the thermoplastic composite is improved, and the surface quality of the thermoplastic composite is guaranteed during the repair process. The shape of the thermoplastic composite material is largely maintained, so that it meets the requirements of emergency use.

Description

A repair method and repair device for thermoplastic composite material damage

technical field

The invention relates to the technical field of composite material manufacturing, in particular to a method for repairing damage to thermoplastic composite materials and a repair device thereof.

Background technique

Compared with thermosetting resin-based composite materials, thermoplastic resin-based composite materials have the advantages of rapid prototyping, raw materials can be stored indefinitely, parts can be heated and formed many times, and waste parts can be recycled. It is economical and environmentally friendly. development requirements. The application of foreign thermoplastic composite materials in military and civil aviation has been completed, from non-load-bearing parts such as aircraft interiors, hatches, covers, fairings, to aircraft fixed front and rear edges, flaps, ailerons, rudders, etc., which are less loaded The position, and then to the transformation of the main load-bearing structure such as the wing box section, the fuselage panel, and the skin. Although the practical application of thermoplastic composites has achieved remarkable results and effectively made up for many problems faced in the manufacture and use of thermosetting composites, the complex service environment makes thermoplastic composites still suffer from various impact damages during use. threaten.

Compared with highly ductile materials such as metals, the energy absorption capacity of composite materials prepared by combining fiber reinforcement and resin matrix is low, so the impact energy can be transmitted deep inside the material, causing externally visible damage, including dents. Pits, cracks, breaks, etc.; and internal non-visible damage, including matrix cracking, interfacial debonding, delamination, or fiber breakage. The impact damage of composite materials may lead to the loss of about 50% of the load-bearing capacity of the composite material structure. Therefore, the special application environment makes the rapid repair of impact damage to thermoplastic composite materials important. The repair methods of composite materials mainly include excavation and mending method, hot pressing method, etc. Most of the previous research work focused on the excavation and mending method, because the excavation and mending method can restore the original structure and mechanical properties of components to the maximum extent, but this requires high technical difficulty and Longer repair times are required, and the cost of repair often approaches or exceeds the cost of replacement parts. Due to the consideration of economic factors and repair efficiency, it is urgent to reduce the repair cost of composite materials in this field and improve the adaptability of composite repair technology in different scenarios.

Contents of the invention

The purpose of the present invention is to provide a repairing method and repairing device for thermoplastic composite damage, so as to solve the above-mentioned problems in the prior art, so that the impact damage of thermoplastic composite can be quickly repaired, which greatly improves the performance of thermoplastic composite. applicability.

In order to achieve the above object, the present invention provides the following scheme: the present invention provides a repair method for thermoplastic composite damage, comprising the following steps:

Determine the damage situation: determine the impact damage location and damage area of thermoplastic composite materials;

Selection of tooling: select two heating plates that match the shape of the area to be repaired on the thermoplastic composite material, and clean the heating plate and apply it on the surface where it meets the thermoplastic composite material release agent;

Selecting a release material: preparing a release material whose structure is larger than the area to be repaired on the thermoplastic composite material;

Heating repair: placing and covering the release material on the area to be repaired on the thermoplastic composite material, covering and pressing a heating plate on the side of the release material away from the area to be repaired, placing The other heating plate is placed on the side of the thermoplastic composite material away from the release material and at a position corresponding to the area to be repaired, and the two heating plates are heated to above the melting temperature of the thermoplastic composite material , and apply the required repairing pressure to the two heating plates, so that the two heating plates clamp the thermoplastic composite material and the release material, and keep it for the required time, then maintain the required repairing pressure and cool the The heating plate is brought to the required temperature, and the heating plate is withdrawn, and the release material on the thermoplastic composite material is cleaned;

Inspection and repair: perform non-destructive testing on the repaired thermoplastic composite material to check the repair effect.

Preferably, the thermoplastic composite material includes a resin matrix, and the resin matrix is filled with reinforcement fibers for enhancing its structural strength.

Preferably, the reinforcement fibers include but not limited to carbon fibers, glass fibers, basalt fibers, and aramid fibers.

Preferably, the resin matrix includes but not limited to PEEK, PAEK, PPS thermoplastic resins.

Preferably, the detection process in the steps of determining damage and inspecting and repairing is non-damage detection, and the non-damage detection adopts ultrasonic scanning detection, ray detection or acoustic emission detection.

Preferably, in the step of selecting a release material, the area of the release material is more than 150% of the area of the area to be repaired, and the release material covers the area to be repaired.

Preferably, in the heating repair step, the heating temperature of the heating plate is 10-25° C. higher than the melting temperature of the thermoplastic composite material.

Preferably, in the heating repair step, the required repair pressure is 1MPa<P<5MPa.

Preferably, in the heating repair step, the required time is 15 minutes to 60 minutes.

Also provided is a repairing device for thermoplastic composite material damage, comprising a hinged upper loading arm and a lower loading arm, one end of the upper loading arm is hinged to an upper support, the other end is connected to a hook, and the lower loading arm corresponds to the One end of the upper support is fixed with a lower support, and one end of the lower loading arm corresponding to the hook is hinged with an electric telescopic rod, and the end of the electric telescopic rod is connected with the hook, and the upper support and The sides of the lower supports close to each other are provided with heating plates capable of covering the area to be repaired, and the two heating plates are held on both sides of the area to be repaired.

Compared with the prior art, the present invention has achieved the following technical effects:

First, by determining the damage situation, selecting tooling, selecting demoulding materials, heating repair, inspection and repair and other repair steps, the low-speed impact damage of thermoplastic composite materials can be effectively repaired, the application ability of thermoplastic composite materials can be improved, and thermoplastic composite materials can be guaranteed. The surface quality of the material during the repair process can greatly maintain the shape of the thermoplastic composite material, making it meet the requirements of emergency use.

Second, drive the upper loading arm and the lower loading arm to rotate through the electric telescopic rod, and then drive the upper support and the lower support to close the mold, so that the two heating plates are clamped on both sides of the area to be repaired, and can reach the temperature of the corresponding melting material , supplemented by two heating plates customized according to the shape of the thermoplastic composite material, can make the resin matrix of the thermoplastic composite material flow to a certain extent, and fill the cracks, delamination and other defects in the composite material under the repair pressure, and then repair the thermoplastic The internal damage of the composite material restores the mechanical properties of the thermoplastic composite material to the greatest extent so that it meets the requirements of use, and can achieve the repair effect of quick disassembly, quick repair, stable shape and reliable quality.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without paying creative labor.

Fig. 1 is the impact damage schematic diagram of CF/PAEK thermoplastic composite material of the present invention;

Fig. 2 is the schematic diagram of the impact damage repair effect of the CF/PAEK thermoplastic composite material of the present invention;

Fig. 3 is the impact damage schematic diagram of CF/PEEK thermoplastic composite material of the present invention;

Fig. 4 is the schematic diagram of the impact damage repair effect of the CF/PEEK thermoplastic composite material of the present invention;

Fig. 5 is a schematic diagram of the entire repair device of the present invention;

Among them, 1-upper support, 2-upper template, 3-pin, 4-upper loading arm, 5-hook, 6-electric telescopic rod, 7-lower loading arm, 8-fastening screw, 9-heating rod, 10-lower formwork, 11-lower support.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The purpose of the present invention is to provide a repairing method and repairing device for thermoplastic composite damage, so as to solve the above-mentioned problems in the prior art, so that the impact damage of thermoplastic composite can be quickly repaired, which greatly improves the performance of thermoplastic composite. applicability.

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1 to 5, this embodiment provides a method for repairing damage to thermoplastic composite materials, especially for repairing damage to high-performance thermoplastic composite materials, including the following steps:

Determine the damage situation: determine the impact damage location and damage area of thermoplastic composite materials;

Selection of tooling: select two heating plates that match the shape of the area to be repaired on the thermoplastic composite material, clean the heating plate, and apply a release agent on the surface where it meets the thermoplastic composite material; preferred , the cleaning agent used in the cleaning operation is a mold cleaner, which can remove impurities and chemical residues on the working surface of the repair tooling. The release agent is a high-temperature release agent, and its temperature resistance level is higher than the processing temperature. The higher temperature resistance level guarantees The release agent will not fail during the repair process, which can make the composite material release smoothly and have a high surface quality;

Selection of release material: Prepare a release material whose structure is larger than the area to be repaired on the thermoplastic composite; preferably, its temperature resistance level is higher than the repair temperature of the thermoplastic composite, and completely covers the impact damage area of the thermoplastic composite. The synergistic use of the mold agent can obtain better demoulding effect and higher surface quality. Specifically, the mold release material can be used to prevent the heating plate from being fully separated from the thermoplastic composite material after the repair is completed, resulting in damage to the surface of the thermoplastic composite material. The impact of the heating plate is damaged, and then through the release material, the heating plate can be contacted with the thermoplastic composite material through the release material, and in the process of demoulding, the release material enables the heating plate to be quickly separated from the thermoplastic composite material, and through The release agent is arranged between the heating plate and the release material, so as to prevent the release material from adhering to the heating plate during the molding process, which will affect the cleaning of the subsequent heating plate; preferably, the release material is made of polyimide Lamination of amine film and high temperature release cloth, thermoplastic composite material and polyimide film, lamination of polyimide film and high temperature release cloth, lamination of high temperature release cloth and heating plate;

Heating repair: place and cover the release material on the thermoplastic composite material to be repaired, cover and press a heating plate on the side of the release material away from the area to be repaired, place another heating plate on the thermoplastic composite material away from One side of the demoulding material, and at the position corresponding to the area to be repaired, heat the two heating plates to above the melting temperature of the thermoplastic composite material, and apply the required repair pressure to the two heating plates, so that the two heating plates clamp the thermoplastic composite material and release material and hold for the required time, then maintain the required repair pressure and cool the heating plate to the desired temperature and evacuate the heating plate and clean the release material from the thermoplastic composite; where the heating plate is heated to thermoplastic Above the melting temperature of the composite material, apply the required repair pressure and maintain the required time, then maintain the repair pressure and cool to the required temperature, the required heating temperature can make the thermoplastic composite resin matrix have a certain flow, and the repair pressure Fill the cracks, delamination and other defects in the composite material under the action, and then repair the internal damage of the thermoplastic composite material, restore the mechanical properties of the thermoplastic composite material to the greatest extent, and make it meet the use requirements;

Preferably, in the heating repair step, the heating temperature of the heating plate (i.e. repair temperature) is 10-25°C higher than the melting temperature of the thermoplastic composite material, the required repair pressure is 1MPa<P<5MPa, and the required time is 15min to 60min; Specifically, the repair temperature T, repair pressure P and repair pressure t are fine-tuned with the thickness of the thermoplastic composite material. When the thickness h of the thermoplastic composite material is <3mm, the repair temperature T>the melting temperature Tm of the thermoplastic composite material is (10～ 15℃), the repair pressure is 1MPa<P<2MPa, 15min<t<30min; when the thickness is 3mm<h<5mm, the repair temperature T> the melting temperature Tm of the thermoplastic composite material is (15～20℃), the repair pressure is 2MPa<P <3MPa, 30min<t<45min; when the thickness is 5mm<h<8mm, the repair temperature T> the melting temperature Tm of the thermoplastic composite material is (20～25°C), the repair pressure is 3MPa<P<5MPa, 45min<t<60min, The repair process can select the appropriate repair conditions according to the thickness of the composite material, and the appropriate temperature can make the resin matrix of the composite material have a certain flow, and under the action of the repair pressure, the defects such as cracks and delamination in the composite material can be filled. , and then repair the internal damage of the thermoplastic composite material, restore the mechanical properties of the thermoplastic composite material to the greatest extent, and make it meet the use requirements;

Inspection and repair: conduct non-destructive testing on the repaired thermoplastic composite material to check the repair effect.

Preferably, the thermoplastic composite material includes a resin matrix filled with reinforcement fibers for enhancing its structural strength, and the composite material of the resin matrix and reinforcement fibers can adapt to complex service environments and meet the requirements of most structures. Preferably, the reinforcement fibers include but not limited to carbon fibers, glass fibers, basalt fibers, and aramid fibers. And preferably, the resin matrix includes but not limited to PEEK, PAEK, PPS thermoplastic resin, so that the entire resin matrix has excellent mechanical properties.

Further, the detection process in the determination of damage and inspection and repair steps is non-damage detection, and non-damage detection adopts ultrasonic scanning detection, ray detection or acoustic emission detection to perform flaw detection and post-repair detection on thermoplastic composite materials to ensure that thermoplastic composite materials The repair effect of the material. Preferably, the non-destructive testing method is ultrasonic scanning. Ultrasonic scanning equipment has the advantage of being portable, and can detect the damage location and damage area of the composite material, which can meet the requirements for rapid detection.

In the step of selecting the release material, the area of the release material is more than 150% of the area of the area to be repaired, and the release material covers the area to be repaired.

In the heating repair step, the heating temperature of the heating plate is 10-25° C. higher than the melting temperature of the thermoplastic composite material.

In the heating repair step, the required repair pressure is 1MPa<P<5MPa.

In the heat repair step, the required time is 15 minutes to 60 minutes.

Also provided is a repairing device for thermoplastic composite material damage, comprising a hinged upper loading arm and a lower loading arm, one end of the upper loading arm is hinged to an upper support, the other end is connected to a hook, and the lower loading arm corresponds to one end of the upper support The lower support is fixed, and the end of the lower loading arm corresponding to the hook is hinged with an electric telescopic rod. The end of the electric telescopic rod is connected to the hook. Heating plates in the area, two heating plates are held on both sides of the area to be repaired. Among them, the upper support is connected with the lower loading arm through the pin-hole structure, and the lower support is fixed on the upper loading arm, so that the loading arm can apply pressure to the template evenly. The two heating plates are customized according to the shape of the damaged area of the thermoplastic composite material, and can quickly Disassembly and replacement; the heating rod is located at the opening of the two heating plates, which can apply a stable temperature through the temperature control system; the electric telescopic rod connects the upper and lower loading arms through the hook, and can exert pressure on the lower template. The tooling can replace the two heating plates It is used to meet the repair needs of composite materials with different shapes, and can be used to repair damage at different positions by extending the loading arm.

As a preferred embodiment of the present invention, if faced with a 150mm×100mm×4.5mm carbon fiber reinforced PAEK thermoplastic composite plate, the repair of impact damage under 25J energy.

Step 1: Use an ultrasonic scanning microscope to conduct non-destructive testing on the carbon fiber reinforced PAEK thermoplastic composite material after impact, and determine that the damage area of the composite material is about 5.4cm ² , and the internal damage shape is oval;

Step 2: Select a flat tooling that is consistent with the shape of the repaired area of thermoplastic composite materials;

Step 3: Use sandpaper and mold cleaner to clean the flat tooling for repairing the impact damage of thermoplastic composite materials, and apply a release agent;

Step 4: cutting the release material whose area is greater than 150% of the impact damage area of the composite material, and making it completely cover the damaged area of the thermoplastic composite material;

Step 5: Bond the thermoplastic composite material with the release material, and the release material is bonded with the flat tooling coated with the release agent;

Step 6: Raise the temperature of the flat tooling to 340 ° C; and apply a pressure of 2 MPa; maintain the temperature and pressure for 30 minutes;

Step 7: Use an ultrasonic scanning microscope to conduct non-destructive testing on the repaired thermoplastic composite material to check the repair effect.

According to the above repair method, the impact damage of the 150mm×100mm×4.5mm carbon fiber reinforced PAEK thermoplastic composite plate under 25J energy can be repaired intact.

As a preferred embodiment of the present invention, if faced with a 150mm×100mm×5mm carbon fiber reinforced PEEK thermoplastic composite material flat plate, the repair of impact damage under 30J energy.

Step 1: Use an ultrasonic scanning microscope to conduct non-destructive testing on the carbon fiber reinforced PEEK thermoplastic composite material after impact, and determine that the damage area of the composite material is about 5.6cm ² , and the internal damage shape is oval;

Step 2: Select a flat tooling that is consistent with the shape of the repaired area of thermoplastic composite materials;

Step 3: Use sandpaper and mold cleaner to clean the flat tooling for repairing the impact damage of thermoplastic composite materials, and apply a release agent;

Step 4: Cut the release material whose area is greater than 150% of the impact damage area of the composite material, and make it completely cover the damaged area of the composite material;

Step 5: Bond the thermoplastic composite material with the release material, and the release material is bonded with the flat tooling coated with the release agent;

Step 6: Raise the temperature of the flat tooling to 390°C; and apply a pressure of 4MPa; maintain the temperature and pressure for 45 minutes;

Step 7: Use an ultrasonic scanning microscope to conduct non-destructive testing on the repaired thermoplastic composite material to check the repair effect.

According to the above repair method, the impact damage of the 150mm×100mm×5mm carbon fiber reinforced PEEK thermoplastic composite plate under 30J energy can be repaired intact.

Adaptive changes made according to actual needs are within the protection scope of the present invention.

It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. . Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In the present invention, specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method and core idea of the present invention; meanwhile, for those of ordinary skill in the art, according to the present invention The idea of the invention will have changes in the specific implementation and scope of application. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims (10)

1. A method for repairing damage of a thermoplastic composite material is characterized by comprising the following steps:

determining the damage condition: determining the impact damage position and the damage area of the thermoplastic composite material;

selecting a tool: selecting two heating flat plates which are matched with the shape of the area to be repaired on the thermoplastic composite material, cleaning the heating flat plates, and smearing a release agent on the surface of the joint of the heating flat plates and the thermoplastic composite material;

selecting a demoulding material: preparing a demolding material with a structure larger than a to-be-repaired area on the thermoplastic composite material;

heating and repairing: placing and covering the demolding material on the thermoplastic composite material at the position of the area to be repaired, covering and pressing one heating flat plate on one side of the demolding material far away from the area to be repaired, placing the other heating flat plate on one side of the thermoplastic composite material far away from the demolding material and corresponding to the position of the area to be repaired, heating the two heating flat plates to be above the melting temperature of the thermoplastic composite material, applying required repairing pressure to the two heating flat plates, enabling the two heating flat plates to clamp the thermoplastic composite material and the demolding material and keeping the required repairing pressure for required time, then keeping the required repairing pressure, cooling the heating flat plates to be at the required temperature, withdrawing the heating flat plates, and cleaning the demolding material on the thermoplastic composite material;

checking and repairing: and carrying out nondestructive testing on the repaired thermoplastic composite material, and checking the repairing effect.

2. The method of repairing damage to a thermoplastic composite of claim 1, wherein the thermoplastic composite comprises a resin matrix filled with reinforcement fibers for enhancing its structural strength.

3. The method of repairing damage to a thermoplastic composite of claim 2 wherein said reinforcement fibers include, but are not limited to, carbon fibers, glass fibers, basalt fibers, aramid fibers.

4. A method of repairing damage to a thermoplastic composite as claimed in claim 3 wherein the resin matrix includes but is not limited to PEEK, PAEK, PPS thermoplastic resin.

5. The method for repairing damage to a thermoplastic composite material according to any one of claims 1 to 4, wherein the steps of determining the damage condition and inspecting the damage are performed by non-destructive inspection using ultrasonic scanning inspection or radiation inspection or acoustic emission inspection.

6. The method according to claim 5, wherein in the step of selecting the mold release material, the area of the mold release material is 150% or more of the area of the region to be repaired, and the mold release material covers the region to be repaired.

7. The method for repairing damaged thermoplastic composite material according to claim 6, wherein in the step of heating and repairing, the heating temperature of the heating flat plate is 10-25 ℃ higher than the melting temperature of the thermoplastic composite material.

8. The method for repairing a damaged thermoplastic composite material according to claim 7, wherein in the step of heat-repairing, the required repairing pressure is 1MPa < P < 5MPa.

9. The method for repairing a damaged thermoplastic composite material according to claim 8, wherein the time required for the heat repairing step is 15 to 60min.

10. A repairing device applying the method for repairing the damage of the thermoplastic composite material as claimed in any one of claims 1 to 9, comprising an upper loading arm and a lower loading arm which are hinged to each other, wherein one end of the upper loading arm is hinged to an upper support, the other end of the upper loading arm is connected to a hook, one end of the lower loading arm corresponding to the upper support is fixed to a lower support, one end of the lower loading arm corresponding to the hook is hinged to an electric telescopic rod, the end of the electric telescopic rod is connected to the hook, one side of each of the upper support and the lower support, which is close to the other side, is provided with a heating flat plate capable of covering the area to be repaired, and the two heating flat plates are clamped on the two side surfaces of the area to be repaired.

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