Research On Electromagnetic Riveting Technology Of CFRP/TC4

With the rapid development of aviation industry,lightweight has become an inevitable trend.High-strength and low-density materials such as titanium alloys and composite materials have become the main force of structural parts in the aviation industry.Riveting is a common method for connecting metal and non-metal,but ordinary riveting is easier to cause initial riveting damage to composite materials,and the quality of interference fit is poor.Electromagnetic riveting has the characteristics of fast forming speed,uniform nail bar expansion,low noise,small equipment volume,etc.,uniform force can effectively reduce the initial riveting damage,so electromagnetic riveting has become one of the effective ways to solve the above problems.Current electromagnetic riveting research is biased towards processing technology.In theoretical research,the electromagnetic riveting process is very complicated,so there is a lack of quantitative description,which is not conducive to large-scale use and optimization.This paper uses the equivalent circle method to simplify the coil model to derive the effective electromagnetic force expression of the electromagnetic riveting drive coil.Then,using the Maxwell module of ANSYS and the transient structure module of workbench,the coupling simulation analysis of the different discharge voltage,the distance between the two coils and the thickness of the driving coil was carried out respectively.The difference between theoretical calculation and simulation is compared,the reason is analyzed,and the position of the driving coil is analyzed to verify the accuracy of the formula.Finally,based on theoretical calculations and finite element analysis results,electromagnetic riveting experiments of CFRP/TC4 plates and tensile experiments of specimens are carried out.After electromagnetic riveting by measuring and calculating the amount of rivet interference,initial invalid load,and the size of the pier head,the influence law of discharge voltage,distance between two coils and driving coil thickness on electromagnetic force and deformation is summarized.Experiments verify the accuracy of theoretical calculations and simulations.This research has guiding significance for the quantitative research of electromagnetic riveting,and has certain theoretical significance and practical application value for the research on the connection of composite materials and metal materials.