TW202237313A - A joint method of fiber thermoplastic composite tube and aluminum alloy tube - Google Patents

Abstract

A jointing method of carbon fiber reinforced thermo plastic tube and aluminum alloy tube includes the following steps: providing an aluminum alloy tube for structure and a thermoplastic composite tube, one end of the aluminum alloy tube is provided with a joint, and one end of the thermoplastic composite tube is provided with an insertion part; sleeve the aluminum alloy tube and the thermoplastic composite tube, so that the insertion part penetrates into the joint, so that the aluminum alloy tube is provided with an overlapping area overlapped with the thermoplastic composite tube, and at least one weld bead is formed by laser assisted bonding in the overlapping area to weld the aluminum alloy tube and the thermoplastic composite tube.

Description

Joining method of fiber thermoplastic composite pipe and aluminum alloy pipe

The invention relates to a method for joining structural carbon fiber thermoplastic composite pipes and aluminum alloy pipes, in particular to a method for joining different materials using laser-assisted metal and plastic material joining methods for metal/carbon fiber thermoplastic composite materials.

Traditional thermoset composite (FRP) is a non-recyclable material, and the prepreg needs to be refrigerated. It has high tensile strength after curing, but it is difficult to shape after curing, and it breaks instantly when it is damaged, and there is almost no buffer time for deformation. The production is done in a stacking manner, which is difficult to produce quickly and automatically. It is labor-intensive and time-consuming, and it is difficult to form injection molding.

The joining of traditional thermosetting thermoplastic composite materials (CFRP) and aluminum alloy pipes, such as bicycle structural parts, is usually done by gluing technology; however, gluing technology is labor-intensive, time-consuming, and difficult to automate. In the future, if structural carbon fiber thermoplastic composites (CFRTP) are used in the bicycle structural parts industry, it will be limited to the use of two-component structural adhesives at room temperature, and the bonding and curing time required to withstand high loads must be more than 24 hours. It's been a long time. At present, taking the bicycle component industry as an example, arc welding is still mostly used for the joining of aluminum alloy and aluminum alloy components. The structural parts need to be heat treated after welding, and laser welding has not yet been applied to the production, let alone aluminum alloy pipe fittings. The application of laser-assisted metal and plastic joining methods with carbon fiber thermoplastic composite pipe fittings, and there is no commercial use of carbon fiber thermoplastic composite materials in bicycle load pipe structural parts in the world, nor the application of the above welding method (such as laser-assisted metal and plastic material bonding method), in the bonding production of bicycle structural parts.

The purpose of the present invention is to provide a method for joining structural fiber thermoplastic composite pipes and aluminum alloy pipes, using laser-assisted metal-plastic material joining technology to weld at least one ring pipe on the joint between thermoplastic composite pipes and aluminum alloy pipes or straight bead for quick joining.

In order to achieve the above object, the present invention provides a method for joining a structural fiber thermoplastic composite pipe and an aluminum alloy pipe, the steps of which include: providing a structural aluminum alloy pipe and a fiber thermoplastic composite pipe, the aluminum alloy pipe One end has a joint, and the fiber thermoplastic composite pipe has an insertion portion at one end; the aluminum alloy pipe and the fiber thermoplastic composite pipe are sleeved, so that the insertion portion penetrates into the joint, so that the aluminum alloy pipe has a section an overlapping area overlapped with the fiber thermoplastic composite pipe; and performing a laser-assisted joining on the overlapping area to form at least one weld bead for welding the aluminum alloy pipe and the fiber thermoplastic composite pipe.

In some embodiments, the aluminum alloy tube is made of AA6061.

In some embodiments, the laser-assisted joining has two weld passes, and the distance between the weld passes is 10 mm to 20 mm.

In some embodiments, the laser-assisted joining is to form a full-circumferential weld around the joint of the aluminum alloy tube or a linear weld parallel to the central axis of the aluminum alloy tube at the overlapping region.

In some embodiments, the bead length of the straight weld is 10 mm to 20 mm.

In some embodiments, the straight line welding is divided into four passes in the radial direction of the overlapping area, one at 12 o'clock, one at 3 o'clock, one at 9 o'clock, and one at 4 o'clock.

In some embodiments, the overlapping surface of the aluminum alloy tube and the fiber thermoplastic composite tube is further roughened.

In some embodiments, before the aluminum alloy tube and the fiber thermoplastic composite tube are sleeved, an adhesive is pre-coated on the overlapped surfaces.

In some embodiments, the overlapping surface of the aluminum alloy tube and the fiber thermoplastic composite tube includes a plane, and before the aluminum alloy tube and the fiber thermoplastic composite tube are socketed, the overlapping surface Apply a glue.

In some embodiments, in the above-mentioned aspect of using the adhesive, the laser-assisted bonding can be performed before the adhesive is cured.

In some embodiments, the glue comprises a thermoset.

The present invention has at least the following features: the proposed laser-assisted joining method of metal and plastic material is suitable for the production of automatic welding without glue. The fiber thermoplastic composite material of the present invention can be applied to structural components, especially to bicycle load-bearing components. Apply laser-assisted metal and plastic material joining technology to aluminum alloy tubes, such as: AA6061T6, and fiber thermoplastic composite materials, such as: carbon fiber thermoplastic composite material tubes, bicycle components, without the need for labor-consuming and time-consuming applications, greatly improving the joining efficiency And aging, if it is reinforced with adhesives, the cost of adhesives can be saved, especially in the future demand for the substantial development of the electric bicycle aluminum (Al) and carbon fiber thermoplastic composite (CFRTP) heterogeneous material application market, which has great potential. The present invention directly applies AA6061T6 aluminum alloy to carbon fiber thermoplastic composite materials and uses laser-assisted metal and plastic materials to join, without heat treatment after welding, still has excellent joint performance, and can be applied to solid components. The invention overcomes the traditional bicycle industry, because the weldment needs heat treatment after welding, and does not directly use the aluminum alloy T6 material, so the invention will greatly save the equipment investment, manufacturing process and time cost of post-weld heat treatment.

1,1a,1b,1': aluminum alloy tube

11, 11a, 11b: joints

2,2a,2b,2': fiber thermoplastic composite pipe

21, 21a, 21b: insertion part

3,3a,3b,3': overlapping area

4,4a,4b,5a,5b,6a,6b,6c,6d: weld bead

A: Laser bonding equipment

B: laser beam

F: bicycle frame

G: joint glue

L: Length

S: Spacing

P: Plane

S11 to S13: Joining steps of fiber thermoplastic composite pipe and aluminum alloy pipe for structural use

[Fig. 1] is a flow chart of the steps of the joining method of the structural fiber thermoplastic composite pipe and the aluminum alloy pipe according to an embodiment of the present invention;

[Fig. 2] is a schematic diagram of electro-radiation assisted bonding according to an embodiment of the present invention;

[Fig. 3] is a schematic view before bonding of a fiber thermoplastic composite tube and an aluminum alloy tube for structure applied to a bicycle frame according to an embodiment of the present invention;

[Fig. 4] is a schematic diagram of Fig. 3 after bonding;

[Fig. 5A] is a schematic view of the welding bead of the structural fiber thermoplastic composite pipe and the aluminum alloy pipe according to an embodiment of the present invention;

[FIG. 5B] is a transfer sectional view along the 5B-5B section line of FIG. 5A;

[Fig. 5C] is a cross-sectional view of Fig. 5A along the section line 5C-5C;

[Fig. 6A] is a circular cross-sectional schematic diagram of a fiber thermoplastic composite pipe and an aluminum alloy pipe for a structure of an embodiment of the present invention;

[FIG. 6B] is a transfer sectional view along the section line 6B-6B of FIG. 6A;

[FIG. 7A] is a schematic diagram of a cross section of a fiber thermoplastic composite pipe and an aluminum alloy pipe for structure according to an embodiment of the present invention; and

[FIG. 7B] is a cross-sectional view taken along the section line 7B-7B of FIG. 7A.

The embodiments of the present invention are described in detail below in conjunction with the drawings. The attached drawings are mainly simplified schematic diagrams, which only schematically illustrate the basic structure of the present invention. Therefore, only components related to the present invention are marked in these drawings. , and the displayed components are not drawn with the number, shape, size ratio, etc. at the time of implementation, and the specifications and sizes at the time of actual implementation are actually an optional design design, and its component layout may be more complex.

The following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the present invention may be practiced. The directional terms mentioned in the present invention, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side", etc., are for reference only The orientation of the attached schema. Therefore, the directional terms used are used to illustrate and understand the application, but not to limit the application. Also, in the specification, unless it is clearly described to the contrary, the word "comprising" will be understood as meaning including the stated elements, but not excluding any other elements.

Please refer to Figure 1 to Figure 4. The steps of the joining method of fiber thermoplastic composite material pipe and aluminum alloy pipe for structure in this embodiment:

Step S11 : providing a structural aluminum alloy pipe 1 and a fiber thermoplastic composite pipe 2 , the aluminum alloy pipe 1 has a joint 11 at one end, and the fiber thermoplastic composite pipe 2 has an insertion portion 21 at one end. It is worth mentioning that the material of the aforementioned aluminum alloy tube may be AA6061. In one embodiment, the aforementioned AA6061 has been heat-treated, for example: T6 heat-treated. The fiber thermoplastic composite pipe 2 can be made by applying the applicant's Republic of China certificate number TW I721488 B "Thermoplastic composite manufacturing device and method", the traditional fiber thermosetting composite material (hereinafter referred to as thermosetting composite material) It is a non-environmentally friendly material that is difficult to recycle and reuse. The prepreg needs to be refrigerated, the production time is long, and injection molding is difficult. When the material is destroyed, it will be destroyed instantly, and there is little buffer and time. Compared with thermosetting composite materials which are non-recyclable materials, thermoplastic composite materials have the advantages of being recyclable and reusable, prepreg materials do not need to be refrigerated, and have good heating formability after curing, and the cross-section can be shaped and diversified. Injection, the forming time is about 10% of the thermosetting composite material, the production cost is lower than that of the thermosetting composite material, and it will not be destroyed immediately when it is damaged, so there is a buffer and time. In one embodiment, the fibers in the fiber thermoplastic composite tube 2 are carbon fibers.

Step S12: Connecting the aluminum alloy tube 1 and the carbon fiber thermoplastic composite tube 2 so that the insertion part 21 penetrates into the joint 11 so that a section of the aluminum alloy tube 1 overlaps with the carbon fiber thermoplastic composite tube 2 The overlap area 3.

Step S13: Using a laser bonding device A to irradiate a laser beam B on the overlapping area 3 to perform a laser assisted metal & plastic joining (LAMP) to form at least one weld in the overlapping area 3 4 to weld the aluminum alloy pipe 1 and the carbon fiber thermoplastic composite pipe 2, as shown in FIGS. 2 to 4 . In one embodiment, after the heat-treated aluminum alloy tube 1 is joined to the fiber-thermoplastic composite tube 2 through laser-assisted bonding, the mechanical strength of the aluminum alloy tube 1 before joining can still be maintained, so the aluminum alloy tube 1 after joining There is no need for heat treatment such as solid solution and aging.

In the aforementioned embodiment, the welding bead 4 of the laser-assisted joining can be two, as shown in FIG. 5A , and the distance S between the welding bead and the welding bead is preferably 10 mm to 20 mm, but it is not limited thereto. .

In some embodiments, the laser-assisted joining is to form a full-circumference weld around the joint 11 of the aluminum alloy tube 1 in the overlapping region 3, such as the weld bead (4a, 4b, 4a, 4b, 5a, 5b).

As shown in FIG. 2 , if the aforementioned weld bead 4 is a straight weld bead, the length L of the weld bead 4 is preferably 10 mm to 30 mm, but not limited thereto.

As shown in Figure 5A and Figure 5C. In some embodiments, the laser-assisted joining is to form a straight line weld parallel to the central axis of the aluminum alloy tube 1 at the overlapping region 3 . Furthermore, the above-mentioned linear welding bead can be welded in four radial directions in the overlapping area 3, one at 12 o'clock, one at 3 o'clock, one at 9 o'clock, and one at 4 o'clock, as shown in Figure 5C. Weld beads (6a, 6b, 6c, 6d).

Moreover, in order to improve the bonding strength between the aluminum alloy pipe 1 and the fiber thermoplastic composite pipe 2 degree, before the above step S12 of the two joined pipe fittings, a glue G can be pre-coated on the overlapping surface of the overlapping area 3, as shown in Figures 6A and 6B, or as shown in Figures 7A and 7B In the embodiment, the overlapping surface of the aluminum alloy tube 1' and the fiber thermoplastic composite tube 2' includes a plane P, and the plane P is located between the aluminum alloy tube 1' and the fiber thermoplastic composite tube 2'. Before joining, a glue G, such as thermosetting glue, is pre-coated on the surface of the overlapping planes P, and then laser-assisted joining is performed. In particular, it needs to be stated that after coating the overlapping surface of the overlapping region 3' with the adhesive G, it is not necessary to wait for the adhesive to cure, and then the laser-assisted bonding process can be performed immediately, for example, under the bonding portion Apply glue and apply laser-assisted bonding on the top, as shown in Figure 7A and Figure 7B. The advantage of this embodiment of gluing plus laser-assisted bonding is that the method of laser-assisted bonding plus gluing can overcome the problems caused by the straight circle of the mold. Insufficient degree of tightness makes the overlapping surface of the pipe fittings not tight enough; under certain conditions, the fiber thermoplastic composite pipe 2 in the inner layer may soften and deform after receiving the laser, possibly due to the influence of the thickness of the pipe fittings and the laser power parameters , so that the overlapping gap with the outer aluminum alloy tube wall increases or even separates, which easily affects the strength of laser welding. At this time, if there is an adhesive coating, this situation can be avoided.

In the above embodiment, before the aluminum alloy tube 1 and the fiber thermoplastic composite tube 2 are socketed, the overlapping surface of the aluminum alloy tube 1 and the fiber thermoplastic composite tube 2 is further roughened, such as sandblasting, Acid etching and other construction methods are used to increase the friction of the surface and improve the joint fastness of the two pipe fittings.

In summary, the present invention preassembles aluminum alloy tubes and fiber thermoplastic composite tubes, and uses laser-assisted metal-plastic material joining methods or laser-assisted metal-plastic material joining methods plus adhesives, especially thermosetting Circumferential welding or linear welding can be made with glue, which can reduce the interference of circumferential welding, and after laser-assisted metal-plastic material joining and welding, the metal material does not need heat treatment such as solid solution and aging, which reduces self-destructive The time and cost of the plastic heat treatment of the vehicle frame (structural parts); if all laser-assisted metal-plastic joints are used (without the use of adhesives), the average shear load of the joint can reach more than 5,911N after verification by the test piece after welding. And it can save the cost of adhesive and the cost of numerous gluing process.

The present invention is applied on the bicycle frame. In the aspect of ISO 4210-6 horizontal force fatigue test, the forward force 600N and the backward force 600N are tested for more than 100,000 cycle tests in the competition sports car (racing bike), and the test is passed in the mountain bike ( mountain bike) with a forward force of 1200N and a backward force of 600N push-pull test for more than 50,000 cycles and passed the test.

The embodiments disclosed above are only illustrative of the principles, features and effects of the present invention, and are not intended to limit the scope of the present invention. Any person familiar with the art can, without departing from the spirit and scope of the present invention, Modifications and changes are made to the above-mentioned embodiments. Any equivalent change and modification accomplished by using the content disclosed in the present invention should still be covered by the scope of the following patent application.

S11 to S13: Joining steps of carbon fiber thermoplastic composite pipe and aluminum alloy pipe for structural use

Claims (12)

A method for joining a fiber thermoplastic composite pipe and an aluminum alloy pipe, the steps of which include: An aluminum alloy tube and a fiber thermoplastic composite tube are provided, one end of the aluminum alloy tube has a joint, and one end of the fiber thermoplastic composite tube has an insertion portion; Sleeve the aluminum alloy tube and the fiber thermoplastic composite tube, the insertion part penetrates into the joint, so that the aluminum alloy tube has an overlapping area overlapped with the fiber thermoplastic composite tube; and A laser-assisted bonding is performed on the overlapping area to form at least one weld bead to weld the aluminum alloy pipe and the fiber thermoplastic composite pipe. The method for joining fiber thermoplastic composite pipes and aluminum alloy pipes according to Claim 1, wherein the material of the aluminum alloy pipes is heat-treated AA6061. The method for joining fiber thermoplastic composite material pipes and aluminum alloy pipes as described in claim 1, wherein the welding bead for the laser-assisted joining is two, and the distance between the welding bead and the welding bead is 10 mm to 20 mm. The method for joining a fiber thermoplastic composite pipe and an aluminum alloy pipe according to claim 1, wherein the laser-assisted joining is to form a weld bead around the aluminum alloy pipe in the overlapping region. The method for joining a fiber thermoplastic composite pipe and an aluminum alloy pipe according to claim 1, wherein the laser-assisted joining is to form a weld bead parallel to the central axis of the aluminum alloy pipe in the overlapping region. The method for joining fiber thermoplastic composite material pipes and aluminum alloy pipes according to claim 5, wherein the length of the weld bead is 10 mm to 30 mm. The method for joining fiber thermoplastic composite pipes and aluminum alloy pipes as described in Claim 5, wherein the welding bead is welded radially in four passes in the overlapping area, respectively in the direction of 12 o'clock and the direction of 3 o'clock , 9 o'clock direction and 4 o'clock direction each. The joining method of fiber thermoplastic composite pipe and aluminum alloy pipe as described in Claim 1, which Before the aluminum alloy tube is socketed with the fiber thermoplastic composite tube, the overlapping surface of the aluminum alloy tube and the fiber thermoplastic composite tube is further roughened. The method for joining structural fiber thermoplastic composite pipes and aluminum alloy pipes as described in claim 1, wherein before the aluminum alloy pipe and the fiber thermoplastic composite pipe are socketed, the overlapping surfaces of the overlapping areas are pre-coated Cloth-adhesive. The method for joining fiber thermoplastic composite pipe and aluminum alloy pipe according to claim 1, wherein the overlapping surface of the aluminum alloy pipe and the fiber thermoplastic composite pipe includes a plane, and the plane is parallel to the aluminum alloy pipe and the aluminum alloy pipe Before the fiber thermoplastic composite pipe is sleeved, an adhesive is pre-coated on the surface of the overlapping plane of the overlapping area. The method for joining fiber thermoplastic composite pipes and aluminum alloy pipes according to claim 9 or 10, wherein the laser-assisted joining is performed before the adhesive is cured. The method for joining fiber thermoplastic composite pipes and aluminum alloy pipes according to claim 9 or 10, wherein the adhesive comprises a thermosetting adhesive.

Images