Research On Ultrasonic Drawing Of Ultra-fine Wire With Impact

Diamond wire saw is a new cutting tool that is obtained through fixing diamond abrasive particles on the surface of metal wires by means of electroplating process or resin combination.It is mainly used for cutting silicon ingots into several silicon wafers of a certain thickness in the photovoltaic industry.However,because its ultra-fine bus material is difficult to process and easy to break,it has become the main technical bottleneck restricting the development of solar power industry,so it is urgent to explore a new processing technology.Studies have shown that the application of ultrasonic vibration in the drawing process of wire can effectively reduce the drawing force,optimize the drawing process and improve the surface quality of wire,so applying this method to the drawing process of the bus may produce better results.Therefore,this paper refers to the idea of ultrasonic drilling and sampling,and proposes a processing technology of percussive ultrasonic vibration drawing,that is,the plastic deformation of the wire is caused by the impact of the die on the end face of the transducer,and the macro and micro analysis of the drawing process is carried out.Macroscopically,the percussive ultrasonic vibration drawing of ultra-fine steel wire is analyzed in this paper,and the collision process between the die and the luffing rod and the contact behavior between the wire and the die are simulated.Using the software ANSYS ls-dyna,a quarter finite element model of ultra-fine steel wire,die and part of the amplitude transformer was established,and then the post-processing was completed with the help of LS-PREPOST,the data of drawing force of wire and impact force of die and amplitude transformer under different amplitudes were obtained,and the stress cloud diagram of the plastic deformation of extra-fine steel wire was drawn.From the microscopic point of view,the forming process of ultra-fine steel wire is simulated from the molecular and atomic point of view.With the help of the molecular dynamics software of LAMMPS,appropriate potential functions,boundary conditions and ensemble were selected,and then the atomic model of the partial contact between the die and the wire was established.After post-processing,the total potential energy and temperature changes of the two processes of relaxation and extrusion were obtained,as well as the motion behavior of the wire atoms,the dislocation evolution of the materials and the distribution of the atomic kinetic energy.The reason and rule of surface formingprocess of wire were explained from atomic Angle.Finally,the impact transducer is designed and tested,and the impact ultrasonic vibration pull-out experimental platform of ultra-fine steel wire is set up.Then the surface morphology of finished wire is observed and compared by SEM.The experimental results show that the impact ultrasonic vibration method can greatly reduce the drawing force of ultra-fine steel wire,with the maximum reduction of about 60%.The larger the amplitude and the lower the drawing speed is set,the better the reduction effect of drawing force will be.Compared with no ultrasonic vibration,this method can effectively improve the surface quality of finished wire.With the gradual increase of amplitude and drawing speed,the effect increases first and then decreases.