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CN-117922036-B - Annular laser-assisted rivetless riveting method for composite material and metal material

CN117922036BCN 117922036 BCN117922036 BCN 117922036BCN-117922036-B

Abstract

A laser-assisted rivetless riveting method for composite material and metal material includes such steps as stacking composite material on metal material, annular laser cutting to form regular through holes, pressing the plate under die to form a pre-tightening layer, plastic deformation of metal material, rivetless riveting, and sectional opening of die cylinder. The invention realizes the continuous process of plastic deformation of the laser cutting composite material and the metal material by utilizing the characteristic that the resin-based composite material and the metal material have difference in the absorption capacity of laser energy of a specific laser wave band, thereby realizing rivetless riveting of the composite material and the metal material in a prefabricated hole-free state, being applicable to connection of the composite material with different resin materials as matrixes and the metal material, and the connector can have a certain tensile strength.

Inventors

  • HU CHENGLIANG
  • HAN DAXIN

Assignees

  • 上海交通大学

Dates

Publication Date
20260505
Application Date
20240219

Claims (7)

  1. 1. A ring laser assisted rivetless riveting method for a composite material and a metal material is characterized in that firstly, the composite material is stacked on the metal material, laser ring cutting of the composite material is completed through ring laser to form a regular through hole, and then a connecting plate is pre-tightened through pressing under a female die; The female die comprises a female die outer barrel, a reverse jacking mechanism and a second supporting block which are sequentially arranged from bottom to top, wherein the male die mechanism comprises a blank holder and a male die arranged in the center of the interior of the blank holder, and the male die is opposite to the reverse jacking mechanism; The anti-jacking mechanism comprises a female die anti-jacking mechanism, a spring cylinder and a first supporting block, wherein the spring cylinder and the first supporting block are arranged outside the female die anti-jacking mechanism; the female die outer cylinder is of a two-section structure and comprises a fixed outer cylinder and a movable outer cylinder, wherein the fixed outer cylinder is connected with a first supporting block of the anti-jacking mechanism, and the movable outer cylinder is connected with a spring cylinder; the female die outer cylinder and the first supporting block are provided with concentric through holes with the same size; The outer part of the female die mold is provided with a female die box body and a box cover plate, wherein the female die outer cylinder is placed on the inner side of the bottom of the female die box body, the bottom of the female die outer cylinder protrudes out of the bottom of the female die box body through a through hole at the bottom of the female die box body, and the female die anti-top, the first supporting block and the upper end face of the spring cylinder are flush and are connected with the second supporting block together.
  2. 2. The ring laser assisted rivetless riveting method of composite material and metal material according to claim 1, wherein the metal material is a metal which is easy to deform plastically, the thickness t 13 =0.5-5.0 mm, the composite material is carbon fiber or glass fiber with thermoplastic or thermosetting resin material as matrix, and the thickness t 12 =0.5-5.0 mm.
  3. 3. The ring laser assisted rivetless riveting method of composite material and metal material according to claim 1, wherein the laser ring cuts and disperses the punctiform laser into ring laser by optical principle, wherein the width of the ring light spot is less than or equal to 0.3mm, the diameter of the ring light spot is less than or equal to 10mm, the power of the laser source is p=at 12 -b, a=120W/mm; The highest temperature T of the composite material of the laser circular cutting machine meets the conditions that et 12 +140℃ < T < et 12 +190 ℃ and e=30 ℃ per mm, the circular cutting is qualified, riveting can be carried out, and when the highest temperature exceeds the range, the circular cutting is unqualified, and the process is finished.
  4. 4. The ring laser assisted rivetless riveting method of composite material and metal material according to any one of claims 1-3, wherein the connecting plate is pre-tensioned with the pressure of q (t 12 +t 13 ), q=0.125 mm/MPa.
  5. 5. The ring laser assisted rivetless riveting method of composite material and metal material according to claim 4, wherein when the punch moves in the direction of the metal material and applies upward forming force, the metal material is plastically deformed in the direction of the die under the pressure of the punch, the height of the generated composite material waste is limited by the anti-propping position of the die while the generated composite material waste is ejected by the deformed metal material, the anti-propping distance d=t 12 + -0.4 mm of the die, the supporting force is provided for the metal material together after the composite material waste contacts with the anti-propping of the die, and the metal material is thinned to 20% t 13 -50%t 13 at the bottom and causes the material to flow radially under the combined action of the forming force and the supporting force.
  6. 6. The ring laser assisted rivetless riveting method of composite material and metal material according to claim 1, wherein the diameter of the male die is , For the cut hole diameter, the bevel angle β=2° -10 °.
  7. 7. The ring laser assisted rivetless riveting method of composite material and metal material according to claim 1, wherein after the riveting is completed, the spring cylinder in the female die is decompressed, the female die is moved by the spring tension to slide the outer cylinder upwards to form an opening, and the recovery of the cutting scraps is completed through the opening.

Description

Annular laser-assisted rivetless riveting method for composite material and metal material Technical Field The invention relates to a technology in the field of heterogeneous plate connection, in particular to a ring laser auxiliary rivetless riveting method for thermoplastic or thermosetting resin matrix composite materials and metal materials. Background The sheet connection of composite materials and metallic materials has wide application in the automotive, rail transit and aerospace fields. Because of the differences in resistance, melting point and thermal conductivity between heterogeneous materials, a homogeneous nugget cannot be formed during welding, and thus effective and safe connection cannot be achieved. At present, a mechanical connection mode is mostly adopted for connecting heterogeneous materials, wherein no-rivet riveting is the most economical mechanical connection process because no fastener exists, no surface damage is caused to a workpiece exists, and a connector has good fatigue resistance, sealing performance and other good characteristics. However, the application of the conventional rivetless riveting is limited by the insufficient plastic deformation capability of the carbon fiber composite material. The existing technology of laser auxiliary engagement connection of thermoplastic composite material and light alloy is characterized in that the corresponding characteristic patterns are processed on the single side surface of a connecting plate, the two are assembled and then the swing laser is used for scanning the surface of the light alloy plate, and a riveting structure of the thermoplastic composite material and the light alloy with extremely high strength is formed under the condition of pressurization, but the preparation cost of the characteristic patterns on the surface of the plate is relatively high, and the technology is not suitable for mass market production. The existing laser heating rivet-free riveting technology is characterized in that the optical fiber tube is embedded in the riveting male die and the female die, the forming area of the riveting material is heated by laser before riveting forming, the material performance is improved, the brittle material is prevented from being easily cracked and broken in the riveting process, meanwhile, the plastic deformation resistance of the material can be reduced, the plate is fully deformed in the forming process, and the connection quality is improved. However, this method of heat softening assisted rivetless riveting is only suitable for thermoplastic composites. In joining thermoset composites, the plastic deformability of the composite cannot be increased by means of heat softening. Disclosure of Invention Aiming at the problems that the existing rivetless riveting process with a prefabricated hole is complex, the positioning is difficult, and the thermosetting composite material cannot be connected by heat-assisted rivetless riveting, the invention provides a ring laser assisted rivetless riveting method for a composite material and a metal material, and the invention is suitable for connecting the composite materials with different resin materials as matrixes and the metal material by utilizing the characteristic that the resin-based composite material and the metal material have different absorption capacities of laser energy of a specific laser band, and realizes independent laser cutting of the composite material and the metal material in a stacking state, thereby realizing rivetless riveting of the metal material and the composite material with a cutting hole in a continuous process. The invention is realized by the following technical scheme: the invention relates to a ring laser auxiliary rivetless riveting method for a composite material and a metal material, which comprises the steps of firstly stacking the composite material on the metal material, and completing laser circular cutting of the composite material through ring laser to form a regular through hole; and under the action of forming force of upward movement of the male die, promoting the metal material to generate plastic deformation and form rivetless riveting with a cutting hole of the composite material, and after connection, opening the female die to move the outer cylinder to form a side opening, thereby completing cutting waste collection, and finally completely opening the female die to take out the connecting plate. The metal material is metal easy to deform and has a thickness t 13 =0.5-5.0 mm, the composite material is carbon fiber or glass fiber with a thermoplastic or thermosetting resin material as a matrix, and the thickness t 12 =0.5-5.0 mm. The sheet material does not require any surface pretreatment prior to joining. The laser circular cutting method comprises the steps of dispersing point-shaped laser into annular laser by using a biconic lens, wherein the width of an annular light spot is smaller than or equal to 0.3mm, the dia