A Glue-Riveting Composite Connection Device between a Pre-Punched Carbon Fiber Composite Material and Aluminum Alloy and Its Control Method

Abstract

The present invention discloses a glue-riveting composite connection device between a pre-opened carbon fiber composite material and aluminum alloy, comprising: a female die; an aluminum alloy plate; a carbon fiber composite material plate with a pre-opened hole at its central position; a blank holder ring disposed on the carbon fiber composite material plate and coaxially arranged with the pre-opened hole; an ultrasonic punch disposed within the blank holder ring and located above the blank holder ring, with a spherical shallow pit provided at the bottom of the ultrasonic punch; a rivet disposed within the blank holder ring and coaxially arranged within the pre-opened hole, the rivet being of a T-shaped structure; a hole passage mechanism axially opened along the rivet; a plurality of through holes radially opened at the lower part of the rivet; and a nail plug fitted within the rivet, with a curved surface recessed upward at the bottom of the nail plug. The present invention can reduce the damage to the carbon fiber composite material plate during the riveting process and solve problems such as unreliable bonding between material layers, glue overflow, and local lack of glue in gluing.

Description

Technical Field

[0001] The present invention relates to a glue-riveting composite connection device between a pre-perforated carbon fiber composite material and aluminum alloy, belonging to the technical field of riveting of composite materials and metal plates. Background Art

[0002] Since the 21st century, with energy conservation and environmental protection becoming the mainstream of the development of all industries, automotive lightweight technology has become the current development direction continuously pursued by the automotive industry due to its significant role in reducing fuel consumption, emissions, and increasing the cruising range of new energy vehicles. Compared with traditional metal materials, carbon fiber composite materials have a series of characteristics such as light weight, high strength, corrosion resistance, earthquake resistance, and flexible component design, and are the most ideal materials for automotive lightweighting.

[0003] However, with the further application of lightweight materials such as carbon fiber composite materials on vehicle bodies, the multi-material hybrid body structure poses challenges to the connection technologies and processes between dissimilar materials. Carbon fiber composite materials are often connected to aluminum alloy on vehicle bodies, and common connection technologies include bolt connection, imprint bonding, self-piercing riveting, etc. These connection technologies all have some obvious defects, so combining different connection methods to combine their advantages has become an important means to optimize the joint quality.

[0004] The glue-riveting composite connection technology combines the continuous sealing performance and fatigue resistance of adhesive bonding and the anti-peeling performance of riveting. When adhesive bonding and riveting fail, they buffer each other, greatly improving the joint strength. However, when applied to the field of connection between composite materials and metals, it still has defects. Carbon fiber composite materials are brittle materials, and riveting will damage the continuity of their fibers and matrix, resulting in problems such as fiber fracture and matrix cracking. If the adhesive layer is cured and then stamped and riveted, the originally cured adhesive layer will be damaged. If the stamping and riveting are carried out when the adhesive layer is in a flowing state, problems such as adhesive overflow and local lack of adhesive will occur, affecting the joint connection performance. Therefore, based on the existing glue-riveting process, new devices and technologies need to be developed to ensure the strength of the connection joint between carbon fiber composite materials and aluminum alloy. Summary of the Invention

[0005] The present invention designs and develops a glue-riveting composite connection device between a pre-perforated carbon fiber composite material and aluminum alloy, and the rivet finally deforms into a "flowering" shape, reducing the possibility of normal peeling of the carbon fiber composite material plate after adhesive bonding failure.

[0006] The present invention also designs and develops a control method for a glue-riveting composite connection device between a pre-perforated carbon fiber composite material and aluminum alloy, using an electromagnetic induction heating coil to generate an alternating magnetic field, and in the alternating magnetic field, controlling the heating temperature by controlling the working current.

[0007] The technical solution provided by the present invention is as follows:

[0008] A bonding-riveting composite connection device between a pre-perforated carbon fiber composite material and aluminum alloy, comprising:

[0009] A female die, which is provided with an annular groove and a conical protrusion upward at the center of the annular groove;

[0010] An aluminum alloy plate, which is arranged on the female die;

[0011] A carbon fiber composite material plate, which is arranged on the aluminum alloy plate, and a pre-perforation is provided at the center position of the carbon fiber composite material plate; the pre-perforation and the annular groove are coaxial;

[0012] A blank holder, which is arranged on the carbon fiber composite material plate and is coaxial with the pre-perforation;

[0013] An ultrasonic punch, which is arranged inside the blank holder and is located above the blank holder, and a spherical pit recessed upward is provided at the bottom of the ultrasonic punch;

[0014] A T-shaped rivet, which comprises:

[0015] A large-diameter nail head and a small-diameter nail leg, the rivet is coaxially arranged in the pre-perforation, and the nail leg is in contact with the upper surface of the aluminum alloy plate;

[0016] A first hole, which is axially arranged at the center of the nail head along the axis of the nail head;

[0017] A connecting cavity, which is axially arranged in the nail leg along the axis of the nail leg; the first hole and the connecting cavity are coaxial and communicate with each other;

[0018] Wherein, four cracks extending radially from the first hole to the outer peripheral edge of the nail head divide the nail head into four segments, and the height of the segments is less than the height of the nail head;

[0019] A plurality of through holes, which are radially arranged in the lower part of the nail leg along the radial direction of the nail leg;

[0020] An inverted T-shaped nail plug, which comprises:

[0021] A small-diameter first end, which extends vertically;

[0022] A large-diameter second end, which extends radially outward from the first end;

[0023] Wherein, the diameter of the first end is larger than the inner diameter of the first hole and abuts against the first hole; the second end has an interference fit with the connecting cavity; the lower surface of the second end is a curved surface recessed upward;

[0024] A closed first space is formed between the inverted T-shaped nail plug and the inner wall of the connecting cavity, and the first space is filled with liquid adhesive.

[0025] Preferably, the T-shaped rivet further comprises:

[0026] A nail neck, which is located between the nail head and the nail leg and is connected to the nail head through a smooth curved surface.

[0027] Preferably, it further comprises:

[0028] An annular connecting groove, which extends along the starting radial direction of the first hole to form a radial groove and is located corresponding to the nail neck.

[0029] Preferably, the upwardly concave curved surface is a spherical surface, which is coaxial with the annular groove.

[0030] Preferably, the lower end of the nail leg is a circular arc cutting edge.

[0031] Preferably, the female die is a long shaft neck, and an electromagnetic induction heating coil is wound around the outside of the long shaft neck.

[0032] Preferably, a transition is made between the first end and the second end through a round table surface.

[0033] Preferably, the height of the nail plug is less than the height between the bottom of the connecting cavity and the plurality of through holes.

[0034] Preferably, it further comprises:

[0035] A pressure sensor, which is arranged on one side of the top of the female die, close to the cavity of the female die;

[0036] A temperature sensor, which is arranged on the other side of the top of the female die;

[0037] An electromagnetic induction heating coil, which is arranged inside the long shaft neck;

[0038] A controller, which is electrically connected to the pressure sensor, the temperature sensor, the ultrasonic transmission punch and the electromagnetic induction heating coil, and is used for receiving the detection data of the pressure sensor and the temperature sensor and controlling the temperature of the adhesive riveting area.

[0039] A control method for a glue riveting composite connection device between a pre-punched carbon fiber composite material and an aluminum alloy, comprising:

[0040] Step 1: Prepare a rivet-nail plug glue-bearing combined component, place the small end of the nail plug inward and the large end outward in the lower cavity of the rivet body, and inject liquid adhesive into the gap between the rivet and the nail plug;

[0041] Step 2: Place the pre-punched carbon fiber plate and the aluminum alloy plate between the female die and the blank holder, the blank holder tightly presses the plates on the female die, and fix the rivet-nail plug glue-bearing prefabricated part to the ultrasonic transmission punch;

[0042] Step 3: The controller controls the ultrasonic transmission punch to impact downward. The ultrasonic transmission punch drives the rivet to move downward through the prefabricated hole of the carbon fiber composite material plate and contact the aluminum alloy plate. Under the action of the extrusion force, the plug extrudes the nail cap and the opening of the nail neck. The nail cap and the nail neck are gradually turned outwards in a split shape to form a rivet buckle. The liquid adhesive inside the rivet flows between the rivet and the aluminum alloy plate, between the plug and the aluminum alloy plate, and then quickly flows into the space between the carbon fiber composite material plate and the aluminum alloy plate through the opening at the edge of the nail leg, completing the bonding while achieving the fitting;

[0043] Step 4: When the ultrasonic transmission punch reaches the bottom dead center and the value of the pressure sensor no longer changes, the electromagnetic induction heating coil starts heating; when the curing degree of the glue layer reaches 1, the curing of the glue layer ends, the ultrasonic transmission punch releases pressure and returns, and the rivet and plug assembly remain in the plate, and the glued rivet joint is completed;

[0044] Among them, the electromagnetic induction heating coil is an important part for controlling the generation of an alternating magnetic field. When in the alternating magnetic field, it will generate heat by itself and cause the temperature to rise, resulting in a change in its resistance value;

[0045] When the temperature rise of the induction heating coil is ΔT, the resistance of the induction heating coil at this time is:

[0046]

[0047] The heat of the induction heating coil is:

[0048]

[0049] By controlling the working current, the heating temperature is controlled. The empirical formula of the working current is:

[0050]

[0051] In the formula, ρ is the resistivity of the induction heating coil, α is the temperature coefficient of resistance of the induction heating coil, ΔT is the change value of the temperature change of the induction heating coil, s is the cross-sectional area of the induction heating coil wire, L is the length of the induction coil wire, R is the resistance of the induction heating coil, t is the working time, and ω is the angular frequency of the alternating current.

[0052] The beneficial effects of the present invention are as follows:

[0053] 1. This method uses a pre-punched carbon fiber composite material plate. Before riveting, the carbon fiber composite material plate is cut by laser to make holes. There are no burrs and no delamination at the hole edges. The prefabricated holes avoid damage to the carbon fiber composite material plate during the riveting process, ensuring the forming quality and mechanical properties of the joint.

[0054] 2. The rivet head and shank of the rivet finally show a "blooming" deformation, reducing the possibility of normal peeling of the carbon fiber composite material plate after the bonding failure. Moreover, the mechanical interlocking of the rivet and the plug is safer and more reliable than the deformation of the punch hitting the rivet head.

[0055] 3. The plug extrudes the central through-hole of the rivet head and shank of the rivet, seals the entire bonded rivet joint, avoids glue overflow, and improves the joint strength and corrosion resistance.

[0056] 4. During the forming process of the entire joint, the rivet head does not directly stamp the material around the prefabricated hole of the carbon fiber composite material plate, reducing the impact damage to the carbon fiber composite material plate.

[0057] 5. The ultrasonic transfer punch transmits ultrasonic vibration to the joint part, which can not only enhance the fatigue strength and corrosion resistance of the joint, but also strengthen the fluidity of the adhesive inside the joint, making it evenly distributed between the rivet, plug assembly and aluminum alloy, and between the aluminum alloy and the carbon fiber composite material plate, improving the strength of the bonded rivet joint.

[0058] 6. Compared with setting solid hot melt adhesive in the rivet, the rivet-plug adhesive-bearing preform of the present invention can place the adhesive in a liquid state at room temperature inside the rivet, with higher bonding strength, and the amount of adhesive-bearing can be changed by changing the specifications of the rivet and the plug, which can be used for mass production.

[0059] 7. After the connection is completed, the rivet and plug assembly remains at the joint position of the plate. Compared with non-rivet riveting, it can better ensure the bearing capacity of the joint.

[0060] 8. Traditional bonded riveting requires the prior production of bonded rivet preforms, including glue layer pretreatment work such as spreading glue on the metal surface and removing impurities. This method does not require the production of bonded rivet preforms, simplifies the pre-process, and is easier to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic cross-sectional structure view of the bonded rivet composite connection device between the pre-opened carbon fiber composite material plate and the aluminum alloy described in the present invention.

[0062] Figure 2 It is a full cross-sectional view of the pre-opened carbon fiber composite material plate described in the present invention.

[0063] Figure 3 It is a full cross-sectional view of the T-shaped open semi-hollow adhesive-bearing rivet described in the present invention.

[0064] Figure 4 It is a top view of the T-shaped open semi-hollow adhesive-bearing rivet described in the present invention.

[0065] Figure 5 It is a full cross-sectional view of the plug described in the present invention.

[0066] Figure 6Full sectional view of the rivet-plug rubber-bearing preform of the present invention.

[0067] Figure 7 Partial sectional view of the distribution positions of the pressure sensor and temperature sensor on the upper surface of the female die of the present invention.

[0068] Figure 8 Process flow chart of the first step of the adhesive-rivet composite connection of the present invention.

[0069] Figure 9 Process flow chart of the second step of the adhesive-rivet composite connection of the present invention.

[0070] Figure 10 Process flow chart of the third step of the adhesive-rivet composite connection of the present invention.

[0071] Figure 11 Process flow chart of the fourth step of the adhesive-rivet composite connection of the present invention. Detailed implementation manners

[0072] The present invention will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can implement it according to the description in the specification.

[0073] As Figures 1-11 shown, the present invention provides an adhesive-rivet composite connection device between a pre-perforated carbon fiber composite material plate and aluminum alloy, including: a rivet 1, a plug 2, an ultrasonic transmission punch 3, a female die 4, a blank holder 5, an electromagnetic induction heating coil 6, a pressure sensor 7, a temperature sensor 8, a carbon fiber composite material plate 9, and an aluminum alloy plate 10.

[0074] As Figure 1 shown, the female die 4 is arranged on a horizontal plane. On the female die 4, an aluminum alloy plate 10 and a carbon fiber composite material plate 9 are sequentially arranged. The aluminum alloy plate 10 covers the notch of the female die 4. On the carbon fiber composite material plate 9, a pre-perforation 91 is opened at the central position. The blank holder 5 is arranged on the carbon fiber plate 9 and is coaxially arranged with the pre-perforation 91. The ultrasonic transmission punch 3 is arranged inside the blank holder 5 and is located above the blank holder 5. A spherical concave pit is arranged at the bottom of the ultrasonic transmission punch 3. The rivet 1 is arranged inside the blank holder and is coaxially arranged in the central pre-perforation 91 of the carbon fiber composite material plate 9. The rivet has a T-shaped structure. On the rivet 1, a channel mechanism is axially opened, and a plurality of through holes 16 are radially opened at the lower part of the rivet 1. The plug 2 has an inverted T-shaped structure and is arranged inside the rivet 1 in a matching manner. The plug 2 and the rivet 1 are in interference fit. Through the cooperation of the rivet 1 and the plug 2, self-locking and anti-loosening of the rivet on one side of the carbon fiber composite material plate are realized, and damage to the opening of the composite material joint during the impact riveting process is reduced.

[0075] As Figure 7As shown in the figure, the female die 4 is of a cylindrical structure. At the top of the female die 4, an annular groove 41 is provided along the central position of the female die 4, and it bulges upward at the center of the groove, presenting a conical shape. And on the outer surface of the female die 4, near the lowest point of the outer surface terminal close to the groove, a long journal 42 is turned out circumferentially for placing the electromagnetic induction heating coil 6.

[0076] The blank holder 5 is of a cylindrical structure. Inside the blank holder 5, a blank holder accommodation cavity is provided axially. The blank holder 5 is arranged above the female die 4. The aluminum alloy sheet 10 and the carbon fiber composite material sheet 9 are both arranged between the blank holder 5 and the female die 4. The aluminum alloy sheet 10 covers the groove 41 of the female die 4, and the carbon fiber composite material sheet 9 is arranged on the aluminum alloy sheet 10. On the carbon fiber composite material sheet 9, at the central position, a pre-opening 91 is provided. The pre-opening 91 is coaxially arranged with the groove 4 and the blank holder accommodation cavity.

[0077] As Figure 3 , Figure 4 shown in the figure, the rivet 1 is of a T-opening semi-hollow structure. On the rivet 1, a channel mechanism is provided axially. The rivet 1 includes a nail head 12, a nail neck 17, and a nail leg 18 connected in sequence. The channel mechanism from top to bottom includes: a self-opening 13, an annular connecting groove 14, and a connecting cavity. The self-opening 13 is provided axially along the nail head and the nail neck. The annular connecting groove 14 is communicated with the self-opening 13. The annular connecting groove 14 is an annular groove and is provided on the nail neck, located below the self-opening 13. The self-opening 13 cuts the nail head 12 and the nail neck 17 into several segments radially outward. An annular groove is machined by sweeping along the inner diameter at the opening of the nail neck 17, that is, the annular connecting groove 14. The outer diameter of the nail leg 18 is the same as the inner diameter of the pre-opening 91 of the carbon fiber composite material sheet 9, so that the nail leg 18 can be just placed into the pre-opening 91. The inner side of the nail leg 18 is an arc-shaped cutting edge. At the lower part of the nail leg 18, through holes 16 are evenly provided radially. Among them, the annular connecting groove 14 can buffer the impact of the nail plug 2 on the rivet 1.

[0078] In the present invention, as a preference, the overall height of the rivet 1 is 18 - 20 mm, the outer diameter of the nail head 12 is 12 - 15 mm, the height is 3 mm, the outer side of the nail head 12 and the nail neck 17 is connected by a smooth curved surface, the height of the nail neck 17 is 2 mm, the outer diameter of the nail neck 17 is the same as the outer diameter of the nail leg and the inner diameter of the pre - opened hole 91 of the carbon fiber composite board 9. The nail leg 18 can just be placed into the pre - opened hole 91, the inner diameter of the nail leg 18 is 6 - 7 mm. A through - hole is opened at the centers of the nail head 12 and the nail neck 17, which is the self - opening hole 13. The diameter of the self - opening hole 13 is not more than 2 mm. The self - opening hole 13 cuts out several split petals 11 from the nail head 12 and the nail neck 17 along the radial direction outwards. The height of the split petals 11 is slightly less than the overall height of the nail head 12 and the nail neck 17 to ensure the sealing of the glue - bearing cavity. The annular connecting groove 14 of the nail neck 17 can play a buffering role in the deformation of the nail neck. A plurality of through - holes 16 are radially opened at the arc - shaped cutting edge 15 of the nail leg 18. Among them, the central axis of the through - hole 16 is vertically and intersectingly arranged with the central axis of the rivet 1.

[0079] As Figure 5 , Figure 6 shown, the nail plug 2 is a T - shaped plug, that is, a stepped cylindrical plug, and the whole is an inverted T - shape. The nail plug 2 includes: a first end 23 and a second end 24. Among them, the first end 23 is a vertical end, and the second end 24 is a horizontal end. The diameter of the first end 23 is larger than the diameter of the self - opening hole 13. The outer - side cylinder diameter of the second end 24 is slightly larger than the inner diameter of the nail leg 18 to ensure that the contact part between the nail leg 18 and the second end 24 of the nail plug 2 is in an interference - fit state. The first end 23 and the second end 24 of the nail plug 2 are smoothly transitioned by a conical surface 25. A chamfer 21 is turned out on the outer side of the end face of the first end 23, and a spherical shallow pit 22 is recessed at the center of the end face of the second end 24. The overall height of the nail plug 2 is less than the height between the bottom of the nail neck 17 and the through - hole 16 of the nail - leg cutting edge.

[0080] As Figure 7 shown, the electromagnetic induction heating coil 6 is wound around the outer side of the long shaft neck 42. On one side of the top of the female die 4, near the annular groove 41, a pressure sensor 7 is arranged, and on the other side, a temperature sensor 8 is arranged. In the present invention, as a preference, both the pressure sensor 7 and the pressure sensor 8 are patch - type, used to monitor the temperature and judge the riveting state. Among them, the controller is electrically connected to the pressure sensor 7, the temperature sensor 8, the ultrasonic transfer punch 3 and the electromagnetic induction heating coil 6 at the same time, and is used to receive the detection data of the pressure sensor 7 and the temperature sensor 8, and control the temperature of the glue - riveting area and the state of the ultrasonic transfer punch 3.

[0081] The present invention also provides a control method for the glue - riveting composite connection device between the pre - opened carbon fiber composite board and aluminum alloy. As Figures 8-11 shown, using the glue - riveting connection device between the pre - opened carbon fiber composite board and aluminum alloy described in the present invention for the glue - riveting process, the process specifically includes:

[0082] Step 1: Prepare the rivet-plug glue-bearing combined component. Place the small end 23 of the plug 2 with the inner side facing inwards and the large end 24 facing outwards in the cavity at the lower end of the rivet neck 17, ensuring an interference fit at the contact part between the rivet leg 18 and the large end 24 of the plug. The plug 2 is placed inside the rivet 1 without falling off, and liquid adhesive is injected into the gap between the rivet 1 and the plug 2.

[0083] Step 2: Place the pre-punched carbon fiber plate 9 and the aluminum alloy plate 10 between the female die 6 and the blank holder 5, with the carbon fiber plate 9 on top and the aluminum alloy plate 10 at the bottom. The blank holder 5 tightly presses the plates onto the female die 6. Place the rivet-plug glue-bearing preform into the central pre-punched hole 91 of the carbon fiber plate, ensuring the coaxiality of the through hole 91 in the carbon fiber composite plate, the blank holder 5, the female die 6, and the rivet-plug glue-bearing preform.

[0084] Step 3: The controller controls the ultrasonic transmission punch 3 to move downward for impact. The rivet 1 squeezes the aluminum alloy plate 10 under the impact of the ultrasonic punch 3. Under the extrusion force, the plug 2 extrudes the nail cap and the opening 13 in the nail neck. The split nail cap and nail neck 11 are radially pressured by the plug 2 and open outwards in a "flowering" shape. The rivet legs 18 open outwards during the process of being pressed into the aluminum alloy material and gradually turn outwards to form a riveting buckle. At the same time, the liquid adhesive inside the rivet 1 flows through the gap between the rivet legs 18 and the plug 2 under the extrusion force, into the space between the rivet 1 and the aluminum alloy plate part 10, between the plug 2 and the aluminum alloy plate part 10, and then quickly flows into the space between the carbon fiber composite plate 9 and the aluminum alloy plate 10 through the opening 16 at the edge of the rivet leg, thus completing the bonding while achieving the fitting.

[0085] Step 4: Until the ultrasonic transmission punch 3 reaches the bottom dead center and the value of the pressure sensor 7 no longer changes, the controller controls the electromagnetic induction heating coil to start heating. When the curing degree of the glue layer reaches 1, the curing of the glue layer ends. The ultrasonic transmission punch 3 relieves pressure and returns, and the rivet 1 and plug 2 assembly remains in the plate, and the glued riveted joint is completed.

[0086] Among them, the electromagnetic induction heating coil is an important link for controlling the generation of an alternating magnetic field. When in the alternating magnetic field, it will generate heat by itself, causing the temperature to rise and its resistance value to change.

[0087] When the temperature rise of the induction heating coil is ΔT, the resistance of the induction heating coil at this time is:

[0088]

[0089] The heat of the induction heating coil is:

[0090]

[0091] By controlling the working current, the heating temperature is controlled. The empirical formula for the working current is:

[0092]

[0093] Wherein, ρ is the resistivity of the induction heating coil, α is the temperature coefficient of resistance of the induction heating coil, ΔT is the change value of the temperature change of the induction heating coil, s is the cross-sectional area of the wire of the induction heating coil, L is the length of the wire of the induction coil, R is the resistance of the induction heating coil, t is the working time, and ω is the angular frequency of the alternating current.

[0094] Although the embodiments of the present invention have been disclosed as above, it is not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the examples shown and described herein.

Claims

1. A control method for a bonding and riveting composite connection device between a pre-perforated carbon fiber composite material and an aluminum alloy, characterized in that, The adhesive-riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy includes: A female die, which is provided with an annular groove and a conical protrusion upward at the center of the annular groove; An aluminum alloy plate, which is arranged on the female die; A carbon fiber composite material plate, which is arranged on the aluminum alloy plate. A pre-perforation is provided at the center position of the carbon fiber composite material plate; the pre-perforation and the annular groove are coaxial; A blank holder, which is arranged on the carbon fiber composite material plate and is coaxial with the pre-perforation; An ultrasonic punch, which is arranged inside the blank holder and is located above the blank holder. A spherical pit recessed upward is provided at the bottom of the ultrasonic punch; A T-shaped rivet, which includes: A large-diameter nail head and a small-diameter nail leg. The rivet is coaxially arranged in the pre-perforation, and the nail leg is in contact with the upper surface of the aluminum alloy plate; A first hole, which is axially arranged at the center of the nail head along the axial direction of the nail head; A connecting cavity, which is axially arranged in the nail leg along the axial direction of the nail leg; the first hole and the connecting cavity are coaxial and communicate with each other; Among them, four cracks extending radially from the first hole to the outer periphery of the nail head divide the nail head into four segments, and the height of the segments is less than the height of the nail head; A plurality of through holes, which are radially arranged in the lower part of the nail leg along the radial direction of the nail leg; An inverted T-shaped nail plug, which includes: A small-diameter first end, which extends vertically; A large-diameter second end, which extends radially outward from the first end; Among them, the diameter of the first end is larger than the inner diameter of the first hole and abuts against the first hole; the second end has an interference fit with the connecting cavity; the lower surface of the second end is a curved surface recessed upward; A closed first space is formed between the inverted T-shaped nail plug and the inner wall of the connecting cavity, which is filled with liquid adhesive; The control method of the adhesive-riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy includes: Step 1: Prepare a rivet-nail plug adhesive-bearing combined component. Place the small end of the nail plug inward and the large end outward in the lower cavity of the rivet body, and inject liquid adhesive into the gap between the rivet and the nail plug; Step 2: Place the pre-perforated carbon fiber plate and the aluminum alloy plate between the female die and the blank holder. The blank holder tightly presses the plates on the female die, and fix the rivet-nail plug adhesive prefabricated part to the ultrasonic transmission punch; Step 3: The controller controls the ultrasonic transmission punch to move downward and impact. The ultrasonic transmission punch drives the rivet to move downward through the prefabricated hole of the carbon fiber composite material plate to contact the aluminum alloy plate part. The nail plug extrudes the openings of the nail head and the nail neck. The segments of the nail head and the nail neck gradually turn outwards to form a riveting buckle. The liquid adhesive inside the rivet flows into the space between the rivet and the aluminum alloy plate part, between the nail plug and the aluminum alloy plate part, and then quickly flows into the space between the carbon fiber composite material plate and the aluminum alloy plate through the openings at the edge of the nail leg, completing the bonding while achieving the fitting; Step 4: When the ultrasonic transmission punch reaches the lower dead center and the value of the pressure sensor no longer changes, the electromagnetic induction heating coil heats up; when the curing degree of the adhesive layer reaches 1, the curing of the adhesive layer ends, the ultrasonic transmission punch releases pressure and returns, and the rivet and nail plug assembly remain in the plate, and the adhesive-riveting joint is completed; Among them, the electromagnetic induction heating coil is an important part for controlling the generation of an alternating magnetic field. When in the alternating magnetic field, it will generate heat by itself, causing the temperature to rise and changing its resistance value. When the temperature rise of the induction heating coil is ΔT, the resistance of the induction heating coil at this time is: The heat of the induction heating coil is: By controlling the working current, the heating temperature is controlled. The empirical formula of the working current is: In the formula, ρ is the resistivity of the induction heating coil, α is the temperature coefficient of resistance of the induction heating coil, ΔT is the change value of the temperature change of the induction heating coil, s is the cross-sectional area of the wire of the induction heating coil, L is the length of the wire of the induction coil, R is the resistance of the induction heating coil, t is the working time, and ω is the angular frequency of the alternating current.

2. The control method of the adhesive riveting composite connection device between the pre-opened carbon fiber composite material and aluminum alloy according to claim 1, characterized in that, The T-shaped rivet further includes: A nail neck, which is located between the nail head and the nail leg and is connected to the nail head through a smooth curved surface.

3. The control method of the adhesive riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy according to claim 2, characterized in that, It further includes: An annular connecting groove, which extends radially along the starting radial direction of the first hole to form a radial groove and is located corresponding to the nail neck.

4. The control method of the adhesive riveting composite connection device between the pre-opened carbon fiber composite material and aluminum alloy according to claim 3, characterized in that The upwardly concave curved surface is a spherical surface, which is coaxial with the annular groove.

5. The control method of the adhesive riveting composite connection device between the pre-opened carbon fiber composite material and aluminum alloy according to claim 1 or 4, characterized in that, The lower end of the nail leg is a circular arc cutting edge.

6. The control method of the adhesive riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy according to claim 5, characterized in that, The female die is a long shaft neck, and an electromagnetic induction heating coil is wound around the outside of the long shaft neck.

7. The control method of the adhesive riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy according to claim 6, characterized in that A transition is made between the first end and the second end through a round table surface.

8. The control method of the adhesive riveting composite connection device between the pre-perforated carbon fiber composite material and the aluminum alloy according to claim 7, characterized in that, The height of the nail plug is less than the height between the bottom of the connecting cavity and the plurality of through holes.

9. The control method of the adhesive riveting composite connection device between the pre-opened carbon fiber composite material and the aluminum alloy according to claim 8, characterized in that, It further includes: A pressure sensor, which is arranged on one side of the top of the female die, close to the cavity of the female die; A temperature sensor, which is arranged on the other side of the top of the female die; An electromagnetic induction heating coil, which is arranged in the long shaft neck; A controller, which is electrically connected to the pressure sensor, the temperature sensor, the ultrasonic punch and the electromagnetic induction heating coil, and is used to receive the detection data of the pressure sensor and the temperature sensor and control the temperature of the adhesive riveting area.

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