Study On The New Glue Riveting Process Of Carbon Fiber-aluminum Alloy Sheet

In recent years,the global industry has developed rapidly.The resulting problems of increasingly depleting energy sources and continuous deterioration of the living environment have become the biggest obstacles to the country's prosperity.In September 2017,the Ministry of Industry and Information Technology officially issued the "Measures for the Parallel Management of Average Fuel Consumption and New Energy Vehicle Credits for Passenger Car Companies".It strongly advocates that new energy passenger cars will gradually transition to a highly energy clean and increase their market penetration.With energy saving and emission reduction,the weight of automobiles is being forced down.Automotive lightweighting is mainly achieved by optimizing structural design,applying high-strength and lightweight materials,and adopting advanced lightweight manufacturing and connection technologies.Connection technology is the most critical and cost-effective link.Aiming at the connection problem of aluminum alloy and carbon fiber composite materials,the article has improved the more mature self-piercing riveting technology in the new connection technology,and has solved the problems of low plasticity,large rebound of carbon fiber composite materials,and punching and drilling The problems of delamination and tearing of the carbon fiber composite material board improve the connective strength of the aluminum alloy / carbon fiber composite material laminate.The research mainly includes the following parts:First,perform a DSC test on this batch of carbon fiber prepreg tape to research the change of resin state with temperature when the carbon fiber prepreg tape in different state.Combined with the traditional,mature autoclave process for making carbon fiber boards,a new glue-rivet joining process for aluminum alloy/carbon fiber composites was formulated: orthogonally layering carbon fiber prepregs to form carbon fiber prefabricated boards and putting them in a refrigerator for half an hour to improve the hardness of the prefabricated board,rivete the carbon fiber prefabricated board and aluminum alloy board,and put the connector into the autoclaxe to solidify and form.By changing the stacking order of aluminum alloy/carbon finer composite materias,changing the number of carbon fiber plies,changing the middle layer,ect.,the factors affecting the strength of the glue-riveted joint are explored.A universal testing machine is used to perform tensile and shear performance tests on the samples to determine the connection strength of the samples under different processes.The stretched sample is made into a metallographic sample,which is observed under a metallographic microscope to clarify the specific failure form and find the theoretical support behind it.Finally,the electron microscope was used to perform energy spectrum analysis on the sample to check the diffusion of the elements and clarify the microscopic connection mechanism to find the best process route to improve the bonding strength of the gluerivet joint.In this paper,a new self-piercing riveting test piece of carbon fiber composite prepreg tape / aluminum sheet is prepared by the method of experimental research and the process of "riveting first,then solidifying after forming".Test pieces with different number of layers of carbon fiber prepreg tape,different stacking order of carbon fiber prepreg tape and aluminum alloy plate were prepared,and tensile properties test and microstructure observation were carried out to explore the two variables' connection strength to the test piece.Impact.In order to test the superiority of the new self-piercing riveting process in improving the connection strength,the self-piercing riveting test specimens under the traditional process were prepared,and the tensile load-displacement curve and metallographic structure of the test specimens under the two processes were performed.Contrast and explore the theoretical basis behind the performance differences.Finally,a new type of rubber-rivet composite connection test piece was also trial-produced and tested for tensile strength.The factors affecting the connection strength were analyzed to further improve the connection strength and test piece preparation efficiency.It provides a certain reference for achieving higher strength and higher efficiency of carbon fiber composite material / aluminum alloy plate.