Study On The Influence Of Cutting Performance With Magnetic Field Change Of Magnetic Induction Based Control Of Free Abrasives For High—efficient Wire Saw

Because the manufacturing cost of the fixed abrasive wire saw is too high,this method is not widely used.The mainstream slicing technology is currently free abrasive wire saw.The past few years,with the rapid development of photovoltaic and semiconductor industry,these industries set higher demand on silicon wafer,which is the size increasing and the thickness decreasing of wafer.As the size,the kerf length and width increases,abrasive particle is more hardly achieved the kerf,and the cutting efficiency of free abrasive wire saw further decrease.To solve this problem,we proposed magnetic induction based control of free abrasives for high-efficient wire saw slicing method.It uses the magnetized wire absorbs magnetic abrasives in the certain region of wire surface,which makes more magnetic abrasives gather in the cutting area to improve the cutting efficiency of wire saw.In this paper,the high gradient magnetic field formed by the magnetized wire,the mechanical conditions and movement pattern of the abrasives in the specific area were studied.And analyzed the difference of cutting performance by magnetic induction based control of free abrasives for high-efficient wire saw and free abrasive wire saw cutting experiment.(1)Copper coated steel wire is a kind of magnetism gathering material.It is widely used in free abrasive wire saw.In uniform magnetic field,the wire is magnetized,then forms high gradient magnetic field.The numerical simulation of the magnetic system was performed by FEM.The results showed that,the magnetic field intensity of high gradient magnetic field changes along with space geometric location of the permanent magnet,which is used as uniform magnetic field.And the validity of simulation results was validated by comparing the simulation results with the theoretical calculation.(2)Because of the high gradient magnetic field,the space around the section of wire is divided into paramagnetic region and reverse magnetic region.The magnetized wire absorbs magnetic abrasives in the paramagnetic region.By force analysis and motion analysis of a single-grit,the result showed the particle track is an irregular parabola.And the validity of theoretical analysis results was validated by comparing the theoretical analysis results with the simulation calculation based on the software Fluent and the experimental results.(3)To compare the difference of cutting performance,established the experimental platform of the novel free abrasive wire saw and free abrasive wire saw.The results indicated the novel free abrasive wire saw is better.And investigated the relation between cutting performance and space geometric location of the permanent magnet.