Study On Sawn Quality Of Brittle Material Influenced By Motions In Multi-wire Saw With Reciprocating And Rocking

The wire sawing technology that uses the small-diameter metal wire as the carrier to drive the abrasive grains to complete the material cutting has been applied for a long time.Wire saw processing technology brings higher productivity,less waste of materials and lower cost compared with traditional disc saw blade cutting.With the rapid development of the IC industry,the photovoltaic industry and the semiconductor lighting industry,the use of wire saw processing technology to achieve wafer slicing has been widely applied,and has gradually become the mainstream processing method.In response to increasingly demanding machining requirements,wire saw machining has evolved from a simple low-speed and short-range motion with reciprocating to a complex multi-wire motion with reciprocating and rocking.The complexity of the processing method,while bringing potential advantages,increases the controllable parameters of the wire saw processing,which leads to the deterioration of the quality of the wire saw processing,and limits the release of advantages that the new wire saw processing technology can bring.In this paper,through the in-depth analysis of the motion mode in multi-wire saw with reciprocating and rocking,the concept of material removal per length of wire is presented,and the theoretical calculation model of material removal per length of wire during material processing is established,which will be used in multiple machining control parameters.The effects of the control parameters are grouped into a unified theoretical model.The influence of material removal per length of wire on the sawn quality was further studied through experiments.Based on the above ideas,the main work of this paper can be summarized as follows:1.The complex motion mode in multi-wire saw with reciprocating and rocking is decomposed into three independent basic movements including wire saw reciprocating motion,feed motion and rocking motion,and the theoretical models of the three motion modes are established.2.A theoretical calculation model of contact length in the processing of multi-wire saw with reciprocating and rocking is established.Theoretical calculations show that the contact length of the square material does not change with the machining process during the wire sawing process,however,the contact length during the processing of the circular material changes with the machining process.The addition of the rocking motion can effectively reduce the cutting contact length.3.The dynamics model of the wire sawing process was established by using Adams simulation software,and the high-speed camera tracking was used to measure the change of the wire bow deflection in the actual sawing process.The experimental results show that the established theoretical model can better predict the wire bow deflection during processing.At the same time,the research also shows that the ratio of normal force to tangential force during processing is the main reason that affects the wire bow deflection.4.Combining the theoretical model of the cutting contact length and the research results of the wire bow deflection,the theoretical model of the material removal per length of wire during the multi-wire sawing with reciprocating and rocking is established.Theoretical analysis shows that under the condition of uniform feed rate,the material removal per length of wire can be stable during the processing of square workpieces due to the influence of contact length,however,the material removal per length of wire during the processing of circular workpieces changes with machining process.5.Through the theoretical model analysis of the material removal per length of wire,the processing technology of the material removal per length of wire keeping stable in the wafer cutting process is proposed,and the variation curve of the feed rate during the processing is reversely deduced.6.Through the cutting experiments of crystal and sapphire,the influence of the material removal per length of wire on the sawn quality is investigated.The results show that the reduce of the material removal per length of wire can effectively reduce the surface roughness of the workpiece.This paper mainly starts from the kinematics in wire sawing,the theoretical model of material removal per length of wire is proposed and established,and a new cutting technology for stabilizing the material removal per length of wire is proposed,and the sawn quality influenced by the material removal per length of wire is found.The research results have a practical guiding significance for deepening the theoretical wire sawing process and optimizing the quality of wire sawing.