Research On Riveting Joint Of Carbon Fiber-reinforced Plastic/Aluminum Alloy

With the continuous improvement of environmental protection requirements in recent years,the development of pure electric vehicles will gradually become the world's consistent goal.The new policies of our country in the field of new energy automobiles continuously promote the long-term development of the new energy automobile industry.The development of lightweight is the only way for fuel automobiles and new energy automobiles.At present,the main way to achieve vehicle lightweight is body lightweight,while the main way to achieve body lightweight is structure lightweight and material lightweight.Aluminum alloy and carbon fibre composite materials,as the main lightweight alternative materials,are more and more used in body parts,which inevitably involves the connection between different materials.In this paper,aiming at the joining problem of carbon fiber composite and aluminium alloy,a new type of rivetless punching joining method of carbon fiber composite and aluminium alloy is designed,which combines the mature punching joining and riveting technology in metal field.It solves the problem that the traditional rivetless stamping connection can not be directly applied to the field of non-metallic materials and metal materials.The research mainly includes the following parts:Based on the analysis of the experimental conditions and the selection of the parameters in the metal stamping connection,a set of rivetless stamping joint die for carbon fiber composite and aluminum alloy was designed independently.Carbon fiber composite laminates were prepared,and the surface treatment methods of carbon fiber composite and aluminium alloy were determined.According to the DSC test results and the curing process parameters of carbon fiber preprepreg provided by the manufacturer,the processing route of rivetless punching connection was determined.The sandwich structure was introduced,and the rivetless punching connection between carbon fiber composite and aluminum alloy was realized in the die according to the processing route.The microstructure analysis was carried out by metallographic microscope.Through tensile shear test and peeling test,the effects of carbon fiber preprepreg layer thickness,preprepreg layer area,sandwich structure powder,sandwich structure metal material,number of metal spraying coatings in sandwich structure and placement order of plates on the connection quality were explored.Suitable parameters of rivetless punching connection between carbon fiber reinforced composites and aluminium alloys.Microstructure analysis was carried out by metallographic microscope and scanning electron microscope to explore the bonding mechanism of sheet metal under the optimum technological parameters.Energy spectrum analysis was carried out by using copper powder as an alternative material of aluminum powder to verify the reasons for the increase of bonding strength of sheet metal.Mixed joints of carbon fiber reinforced composites and aluminium alloys were studied.By choosing glued,riveted and bolted joints to carry out mixed connection experiments and to test the tensile properties,the application environments of different mixed connection modes are determined,which provides a reference for the exploration of hybrid connection.