KR20230162272A - Metal polymer composite - Google Patents

Abstract

A metal-resin composite is disclosed. The metal-resin composite of the present invention comprises: a metal member having a plurality of concave grooves processed on a first surface; and a resin member forming a second surface joined to the first surface and permeating the inside of the concave grooves on the second surface in a liquid phase, wherein the concave grooves are spaced apart in a first direction so as to form a maximum bonding force in the first direction. According to the present invention, it is possible to provide a metal-resin composite formed to form a more solid bonding force against an external force in a specific direction.

Description

Metal resin composite {METAL POLYMER COMPOSITE}

The present invention relates to a metal resin composite, and more specifically, to a metal resin composite that forms bonding force by filling microscopic pores formed on the surface of a metal with a resin.

Currently, the demand for ultra-high-strength steel is increasing to respond to the strengthening of automobile environmental laws and crash safety laws, but it is very difficult to satisfy automobile regulations based on this. Therefore, the demand for composite materials is emerging.

There are various joining technologies for composite materials such as mechanical joining, bonding, and welding, but due to technical difficulties, joining such as steel-CFRP (carbon fiber reinforced plastics) and aluminum-CFRP is only applied to some luxury cars and is not commercialized. It is not done.

In particular, epoxy-based general thermosetting CFRP has difficulty in application to mass-produced vehicles due to low productivity due to the long cycle time of the impregnation and curing process, as well as difficulty in recycling.

HPCi (Heat Press Cool-integrative) scratches a metal sheet to a depth of 200㎛ or more through laser pretreatment, presses and heats the pretreated metal and thermoplastic plastic through the ram of the head, and then the thermoplastic resin liquefies during the heating process. It is a dissimilar material joining technology that penetrates and joins metal structures.

Thermoplastic resin molding technologies such as Long Fiber Thermoplastic (LFT), Prepreg Compression Molding (PCM), and Wet Compression Molding (WCM) have a very short molding time (less than 10 seconds) compared to thermosetting resins and can be recycled by heat, making them highly productive and efficient. .

In this regard, Republic of Korea Patent Publication No. 2019-0042571 (hereinafter referred to as 'prior document') discloses a hybrid composite between a metal surface and a polymer material surface and a method for manufacturing the same.

The hybrid composite of the prior literature relates to a hybrid composite formed between a first coupling portion having a metal surface and a second coupling portion having a polymer material surface, wherein the metal surface includes a micro-structured recess, and this recess is a micro-structured recess. It has a width and depth with dimensions in the range of meters and is at least partially filled with a polymeric material, so that the metal surface area of the microstructured recess is at least partially directly covered with the polymeric material of the second joint.

The hybrid composite manufacturing method in the prior literature involves repeatedly irradiating the metal surface with a laser beam having short-wave pulses and/or ultra-short-wave pulses to create a recess with a depth/width ratio (s/d) of at least 5 below the metal surface. It is configured to form.

The metal surface area of the microstructured recess exhibits a fully nanostructure, the microstructured recess is in the form of a blind hole or through hole completely passing through the first bond, the aspect ratio, i.e. the ratio of depth/width, is greater than 5, and the first bond Characterized in that there is at least one bonding connection based on adhesive and/or covalent bonding forces between the nanostructured metal surface area of the secondary microstructured recess and the polymer material surface of the second bonding portion.

There are various external forces applied to automobile parts. For example, the force applied to the car seat includes the load of the occupant, the force due to the occupant's tilt, and the vibration energy of the vehicle.

The occupant's load may be applied to the car seat in the direction of gravity. And the tilt of the occupants is mainly caused by changes in the acceleration of the vehicle. Therefore, when the vehicle is driven, repeated external force may be applied to the car seat in the direction of vehicle travel and the opposite direction.

There may be a direction of external force mainly applied to the car seat frame depending on the type of vehicle and each part (seat, backrest, etc.). Therefore, it is desirable in terms of productivity and cost reduction to manufacture the metal and resin of the automobile seat frame, which is manufactured as a composite, to have a stronger bonding force against external forces in a specific direction.

However, since the hybrid composite of the prior literature forms a generally uniform adhesion and/or bonding force across the entire metal surface, there is a problem in that it is difficult for the metal and resin produced as a composite to form a more robust bonding force against external force in a specific direction.

There are a variety of parts manufactured from metal-resin composites other than automobile seat frames, and there may be a direction of external force that mainly acts on each part. Therefore, the production of a metal-resin composite considering the direction of external force is required.

Republic of Korea Patent Publication No. 2019-0042571 (Publication date: 2019.04.24)

The purpose of the present invention is to provide a metal-resin composite that forms a more robust bonding force against external force in a specific direction.

The above object is, according to the present invention, a metal member having a plurality of concave grooves machined on its first surface; and forming a second surface joined to the first surface, comprising a resin member in which liquid permeates into the concave groove on the second surface, wherein the concave grooves form the maximum bonding force in the first direction. This is achieved by a metal-resin composite characterized by being spaced apart along one direction.

The concave grooves may be formed long in a direction perpendicular to the first direction, and the distance between them may decrease toward the front and rear of the first direction.

The concave grooves may be formed long in a direction perpendicular to the first direction, and may be formed to become deeper toward the front and rear of the first direction.

The concave grooves may be formed long in a direction perpendicular to the first direction and inclined toward the front and rear of the first direction.

The concave grooves are formed by laser processing of the first surface, and protrusions on which liquefied metal is deposited are formed along the circumference of the concave groove on the first surface, and the protrusions are directed forward and backward in the first direction. It can be made to become increasingly tilted.

The concave grooves may be formed in a direction perpendicular to the first direction and may have a zigzag or wave shape.

The concave grooves may be formed to form concentric circles with the same center and different radii.

The concave grooves are formed by laser processing of the first surface, and the concave grooves may be inclined as they become farther away from the center of the concentric circle.

According to the present invention, the concave grooves are spaced apart along the first direction to form a maximum bonding force in the first direction, thereby providing a metal-resin composite that forms a more robust bonding force against external force in the first direction.

In addition, the distance between the concave grooves decreases, becomes deeper, or is inclined toward the front and rear in the first direction, thereby providing a metal-resin composite in which the bonding force to resist external force in the first direction is improved. .

In addition, the concave grooves are formed in a direction perpendicular to the first direction and form a zigzag or wave shape, thereby providing a metal-resin composite in which the bonding force to resist external forces in the first direction as well as other than the first direction is improved. .

In addition, protrusions on which liquefied metal is deposited by laser processing are formed along the circumference of the concave groove on the first surface, and the protrusions are inclined toward the front and rear in the first direction, creating a bonding force that resists external force in the first direction. It is possible to provide a metal resin composite made to improve this.

In addition, the concave grooves form concentric circles with the same center and different radii, thereby providing a metal-resin composite that forms a more solid bonding force in all directions around the center of the concentric circle.

In addition, the concave grooves are inclined as they move away from the center of the concentric circle, making it possible to provide a metal-resin composite in which the bonding force to resist external force is improved in all directions around the center of the concentric circle.

1 is a cross-sectional view showing a metal-resin composite according to an embodiment of the present invention.
FIG. 2 is a diagram briefly showing a method of manufacturing the metal resin composite of FIG. 1.
Figure 3 is a partial cross-sectional view showing the joint surface of the metal member and the resin member in the pressing/heating step of the method for manufacturing the metal-resin composite of Figure 2.
4 to 7 are views showing the first surface of a metal member of a metal-resin composite according to an embodiment of the present invention, on which a plurality of various concave grooves are machined.
Figures 8 and 9 are cross-sectional views taken along line AA' of Figure 4.
Figures 10 and 11 are partial cross-sectional views of Figure 8.
Figure 12 is a partial cross-sectional view of Figure 9.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. However, in describing the present invention, descriptions of already known functions or configurations will be omitted to make the gist of the present invention clear.

The metal-resin composite of the present invention is made to form a more robust bonding force against external force in a specific direction.

Figure 1 is a cross-sectional view showing a metal-resin composite 10 according to an embodiment of the present invention.

FIG. 2 is a diagram briefly showing the manufacturing method (S100) of the metal resin composite 10 of FIG. 1.

FIG. 3 is a partial cross-sectional view showing the joint surface of the metal member 100 and the resin member 200 in the pressing/heating step (S120) of the manufacturing method (S100) of the metal resin composite 10 of FIG. 2.

As shown in FIG. 1, the metal-resin composite 10 according to an embodiment of the present invention is made to form a bonding force by resin filled in microscopic holes formed on the metal surface, and includes a metal member 100 and a resin member ( 200).

As shown in FIG. 1, the metal member 100 forms a first surface 101 on one side. The metal member 100 may have a plate or block shape.

The first surface 101 refers to a surface joined to the second surface 201 of the resin member 200. The first surface 101 may be a flat surface. Alternatively, the first surface 101 may be a curved surface. The first surface 101 and the second surface 201 may have substantially the same shape.

The metal member 100 may be made of copper (Cu), iron (Fe), aluminum (Al), titanium (Ti), nickel (Ni), chromium (Cr), etc. Alternatively, the metal member 100 may be an alloy thereof.

A plurality of concave grooves 112 are machined on the first surface 101 of the metal member 100. The concave groove 112 refers to a concave groove based on the first surface 101. The concave groove 112 may be formed by the laser device (L). When forming the concave groove 112 by a laser, liquefied metal may be deposited around the concave groove 112.

Accordingly, a protrusion 111 on which liquefied metal is deposited can be formed along the circumference of the concave groove 112. The protrusion 111 may protrude in the normal direction of the first surface 101 along the circumference of the concave groove 112. The height of the protrusion 111 can create the effect of increasing the depth of the concave groove 112.

As shown in FIG. 1, the resin member 200 forms a second surface 201 on one side. The resin member 200 may have a plate or block shape.

The second surface 201 refers to a surface joined to the first surface 101 of the metal member 100. The second surface 201 may be a flat surface. Alternatively, the second surface 201 may be a curved surface. The first surface 101 and the second surface 201 may have substantially the same shape. Hereinafter, the surface where the first surface 101 and the second surface 201 are joined will be referred to as a 'joint surface'.

The resin member 200 may be made of thermoplastic resin. As an example, the resin member 200 is made of polypropylene (PP), polyacetal (POM), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), acrylonitrile butadiene styrene (ABS), and polyethylene (PE). , polybutylene terephthalate (PBT), epoxy, etc. Alternatively, the resin member 200 may be made of carbon fiber reinforced plastic (CFRP).

The resin member 200 is solidified after the liquid penetrates into the concave groove 112 on the second surface 201. Therefore, the metal member 100 and the resin member 200 form a mechanical bonding force at the joint surface.

As shown in FIG. 2, the manufacturing method (S100) of the metal-resin composite 10 may include a laser pre-treatment step (S110) and a pressing/heating step (S120).

The laser preprocessing step (S110) is performed by the laser device (L). The laser device L may include a continuous laser beam source or a pulsed laser beam source. The laser device L forms a plurality of scratches 110 on the first surface 101 of the metal member 100. As shown in Figure 1, the scratch 110 includes a protrusion 111 and a concave groove 112.

The concave groove 112 is formed by the energy of the laser. The concave groove 112 refers to a concave groove based on the first surface 101. The concave groove 112 may have a depth of 200 μm or more. A protrusion 111 on which liquefied metal is deposited is formed around the concave groove 112.

The protrusion 111 protrudes in the normal direction of the first surface 101 along the circumference of the concave groove 112. The height of the protrusion 111 can create the effect of increasing the depth of the concave groove 112. Therefore, the mechanical bonding strength of the metal member 100 and the resin member 200 at the joint surface can be improved.

The pressing/heating step (S120) is performed by the press device (1) and the heating device (2). In the compressing/heating step (S120), the metal member 100 and the resin member 200 are first compressed using a pair of press devices 1. That is, the first surface 101 and the second surface 201 come into close contact, and the metal member 100 and the resin member 200 are compressed.

Then, the metal member 100 is heated using the heating device 2 to liquefy the resin member 200 at the joint surface. The heating device 2 includes an induction heating coil. When current is applied to the induction heating coil, a magnetic field is generated to inductively heat the metal member 100.

As shown in Figure 3, the liquefied resin penetrates into and fills the concave groove 112. Afterwards, the operation of the heating device 2 stops, and the liquefied resin solidifies again to form a mechanical bond between the metal member 100 and the resin member 200.

The metal resin composite 10 according to an embodiment of the present invention is made by scratch processing a metal plate through a laser pretreatment operation, so that the thermoplastic resin disposed on the metal plate is liquefied by heating and penetrates into the metal structure and is bonded, thereby forming screws, rivets, Not only is it possible to join without additional materials such as adhesives, but it also has the advantage of being able to join regardless of whether it is a single fiber, a long fiber, or a continuous fiber.

4 to 7 are diagrams showing the first surface 101 on which various concave grooves 112 of the metal member 100 of the metal resin composite 10 according to an embodiment of the present invention are processed.

As shown in FIG. 4, in the laser pre-processing step (S110), scratches 110 may be formed long in a direction perpendicular to the first direction (X). Scratch 110 includes a protrusion 111 and a concave groove 112. Hereinafter, the direction perpendicular to the first direction (X) on the first surface 101 will be referred to as the 'second direction (Y)'.

Accordingly, within the concave groove 112, the metal member 100 and the resin member 200 form a wide contact surface in the first direction (X). Accordingly, the metal resin composite 10 combined in the pressing/heating step (S120) forms maximum bonding force in the first direction (X).

Metals and plastics are materials with different coefficients of thermal expansion. In general, plastic is a material with a coefficient of linear expansion that is about 10 times greater than that of metal.

Therefore, the conventional composite of metal and resin had a problem with a high possibility of cracking at low temperatures. Conventional metal-resin composites mainly cracked at edge areas where there was a large displacement between the metal and resin due to thermal expansion or thermal contraction.

As shown in FIG. 4, the scratches 110 are formed long in the second direction (Y), and the distance between them may decrease toward the front and rear of the first direction (X). Therefore, the metal-resin composite 10 according to an embodiment of the present invention can minimize the occurrence of cracking at the edges due to thermal expansion or thermal contraction with respect to the first direction (X).

As shown in FIG. 5, the scratches 110 are formed in the second direction (Y) and may have a zigzag or wave shape. Accordingly, within the concave groove 112, the metal member 100 and the resin member 200 form a wide contact surface in the first direction (X) and also form a contact surface in the second direction (Y).

Therefore, the metal resin composite 10 combined in the pressing/heating step (S120) not only forms the maximum bonding force in the first direction (X), but also forms a certain level of bonding force in the second direction (Y). Therefore, the metal resin composite 10 according to an embodiment of the present invention has the advantage of being able to differently adjust the bonding force in the first direction (X) and the second direction (Y).

As shown in FIG. 6, the scratches 110 form a zigzag or wave shape in the second direction (Y), and the distance between them may decrease toward the front and rear of the first direction (X). Therefore, the metal resin composite 10 according to an embodiment of the present invention can minimize the occurrence of cracking at the edge due to thermal expansion or thermal contraction based on the first direction (X) and the second direction (Y).

As shown in FIG. 7, the scratches 110 may form concentric circles with the same center and different radii. Therefore, the metal-resin composite 10 according to an embodiment of the present invention has the advantage of forming a constant bonding force in all directions around the center of the concentric circle.

As the scratches 110 move away from the center of the concentric circle, the distance between them may decrease. Therefore, the metal resin composite 10 according to an embodiment of the present invention can minimize the occurrence of cracking at the edges due to thermal expansion or thermal contraction in all directions centered on the center of the concentric circle.

Figures 8 and 9 are cross-sectional views taken along line A-A' of Figure 4.

As shown in FIG. 8, the laser device L may form scratches 110 on the first surface 101 by irradiating a laser from above the normal direction of the first surface 101. θ in FIG. 8 means 90 degrees.

RP in FIGS. 8 and 9 refers to a reference surface (RP) that passes through the center of the first surface 101 and forms a right angle to the first surface 101.

X ₀ in FIGS. 8 and 9 means the first direction (X) coordinate of the reference surface (RP). X ₁ means a first direction (X) coordinate located in the first direction (X) than the reference surface (RP). X ₂ means a first direction (X) coordinate located in the first direction (X) than X ₁ . X ₃ means a first direction (X) coordinate located in the first direction (X) than X ₂ .

θ ₀ in FIG. 9 means 90 degrees. θ ₁ means an angle less than 90 degrees. θ ₂ means an angle smaller than θ ₁ .

Figures 10 and 11 are partial cross-sectional views of Figure 8.

As shown in FIG. 10, the laser device L irradiates a laser from above the normal direction of the first surface 101 to form scratches 110 on the first surface 101, in the first direction (X). The depth of the concave grooves 112 can be formed to be constant along .

Z ₀ in FIG. 10 means the depth of the concave groove 112 at X ₀ . Z ₁ means the depth of the concave groove 112 in X ₁ . Z ₂ means the depth of the concave groove 112 at X ₂ . In Figure 10, Z ₀ =Z ₁ =Z ₂ .

As shown in FIG. 11, the laser device L irradiates a laser from above the normal direction of the first surface 101 to form scratches 110 on the first surface 101, in the first direction (X). The depth of the concave grooves 112 can be formed deeper toward the front and rear of .

Z ₀ in FIG. 11 means the depth of the concave groove 112 at X ₀ . Z ₁ means the depth of the concave groove 112 in X ₁ . Z ₂ means the depth of the concave groove 112 at X ₂ . In FIG. 10, Z ₀ <Z ₁ <Z ₂ .

Accordingly, within the concave groove 112, the metal member 100 and the resin member 200 form a wider contact surface in the first direction (X) toward the front and rear of the first direction (X). Therefore, the metal-resin composite 10 according to an embodiment of the present invention can minimize the occurrence of cracking at the edges due to thermal expansion or thermal contraction with respect to the first direction (X). Additionally, the mechanical bonding strength of the metal member 100 and the resin member 200 at the joint surface can be improved.

Figure 12 is a partial cross-sectional view of Figure 9.

As shown in FIG. 12, the laser device L may form scratches 110 on the first surface 101 by irradiating a laser from above the normal direction of the reference surface RP.

Accordingly, the concave grooves 112 may be formed long in a direction perpendicular to the first direction (X) and inclined toward the front and rear of the first direction (X). Additionally, the protrusions 111 may form a shape that is inclined toward the front and rear in the first direction (X).

Z ₀ in FIG. 12 means the depth of the concave groove 112 at X ₀ . Z ₁ means the depth of the concave groove 112 in X ₁ . Z ₂ means the depth of the concave groove 112 at X ₂ . The laser device (L) can output a laser with greater energy toward the front and rear of the first direction (X). Accordingly, the protrusions 111 may be formed as Z ₀ =Z ₁ =Z ₂ even if they are inclined toward the front and rear in the first direction (X).

Accordingly, within the concave groove 112, the metal member 100 and the resin member 200 form a contact surface that becomes wider toward the front and rear in the first direction (X). Therefore, the metal resin composite 10 according to an embodiment of the present invention can further minimize the occurrence of cracking at the edge due to thermal expansion or thermal contraction with respect to the first direction (X). Additionally, the mechanical bonding strength of the metal member 100 and the resin member 200 at the joint surface can be improved.

As shown in FIG. 7, the scratches 110 form concentric circles with the same center and different radii, but the laser device L forms a concentric circle based on the normal direction of the first surface 101. Scratches 110 may be formed on the first surface 101 by irradiating a laser from above.

CP in FIG. 7 refers to a reference point (CP) located above the concentric circle based on the normal direction of the first surface 101. The laser device (L) can irradiate laser at the reference point (CP).

Therefore, as shown in FIG. 12, the concave grooves 112 may form a shape that is inclined as the distance from the center of the concentric circle increases. Additionally, the protrusions 111 may form a shape that is inclined as it moves away from the center of the concentric circle.

Therefore, the metal-resin composite 10 according to an embodiment of the present invention can further minimize the occurrence of cracking at the edges due to thermal expansion or thermal contraction in all directions centered on the center of the concentric circle.

According to the present invention, the concave grooves 112 are spaced apart along the first direction (X) to form a maximum bonding force in the first direction (X), thereby forming a more robust bonding force against external force in the first direction (X). It is possible to provide a metal resin composite (10) made of.

In addition, the concave grooves 112 are formed to improve the coupling force to resist external force in the first direction (X) by decreasing the distance between them, deepening the depth, or tilting toward the front and rear of the first direction (X). It is possible to provide a metal resin composite (10).

In addition, the concave grooves 112 are formed in a direction perpendicular to the first direction (X) and form a zigzag or wave shape, so that the bonding force resists external forces other than the first direction (X) as well as the first direction (X). It is possible to provide a metal resin composite (10) made to be improved.

In addition, protrusions 111 on which liquefied metal is deposited by laser processing are formed along the circumference of the concave groove 112 on the first surface 101, and the protrusions 111 are located at the front and rear in the first direction (X). By being inclined toward , it is possible to provide a metal-resin composite 10 in which the bonding force to resist external force in the first direction (X) is improved.

In addition, the concave grooves 112 form concentric circles with the same center and different radii, thereby providing the metal-resin composite 10 to form a more solid bonding force in all directions around the center of the concentric circle. It becomes possible.

In addition, the concave grooves 112 are inclined as they move away from the center of the concentric circle, making it possible to provide the metal-resin composite 10 in which the bonding force to resist external force is improved in all directions around the center of the concentric circle.

Although specific embodiments of the present invention have been described and shown above, it is known in the art that the present invention is not limited to the described embodiments, and that various modifications and changes can be made without departing from the spirit and scope of the present invention. This is self-evident to those who have it. Accordingly, such modifications or variations should not be understood individually from the technical idea or viewpoint of the present invention, and the modified embodiments should be regarded as falling within the scope of the claims of the present invention.

10: Metal resin composite
100: Metal member 200: Resin member
101: Side 1 201: Side 2
110: Scratch L: Laser device
111: Protrusion 1: Press device
112: concave groove 2: heating device
RP: Reference plane
CP: reference point Y: second direction
S100: Manufacturing method
S110: Laser pre-processing step
S120: Compression/heating step

Claims (8)

A metal member having a plurality of concave grooves machined on its first surface; and
Forming a second surface joined to the first surface, and comprising a resin member whose liquid permeates into the concave groove on the second surface,
The concave grooves are spaced apart along the first direction to form maximum coupling force in the first direction,
Metal resin composite. According to paragraph 1,
The concave grooves are formed long in a direction perpendicular to the first direction, and the distance between them decreases toward the front and rear of the first direction.
Metal resin composite. According to paragraph 1,
The concave grooves are formed long in a direction perpendicular to the first direction and become deeper toward the front and rear of the first direction.
Metal resin composite. According to paragraph 1,
The concave grooves are formed long in a direction perpendicular to the first direction and are inclined toward the front and rear of the first direction.
Metal resin composite. According to paragraph 1,
The concave grooves are formed by laser processing of the first surface, and a protrusion on which liquefied metal is deposited is formed along the circumference of the concave groove,
The protrusions are inclined toward the front and rear in the first direction,
Metal resin composite. According to paragraph 1,
The concave grooves are formed in a direction perpendicular to the first direction and form a zigzag or wave shape.
Metal resin composite. According to paragraph 1,
The concave grooves have the same center and form concentric circles with different radii,
Metal resin composite. In clause 7,
The concave grooves are formed by laser processing of the first surface,
The concave grooves are inclined as they move away from the center of the concentric circle.
Metal resin composite.

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