Processing Device Design And Experimental Research Of Multi-wire WEDM

SiCp/Al composites shows great prospect in the field of electronicpackaging for its excellent thermal and mechanical properties. To be a substrateof semiconductor materials, one important process of processing of SiCp/Alcomposites as one of electronic packaging material is slicing. The mostly usedslicing process is multi-wire cutting technology, which is essentially a kind ofgrinding. WEDM cutting technology is also a kind of feasible slicing method.Since it’s a kind of non-contact processing, there is no direct cutting force, it canavoid scratches on the surface of the cutter slice processed by multi-wire saw andcan decrease the kerf loss, while the equipment cost is low. But WEDMprocessing can only cut a slice one time, machining efficiency of which is farless than multi-wire saw. In this paper, In order to improve the efficiency ofWEDM slicing processing, the multi-wire EDM slicing processing of SiCp/Alcomposites material was studied.First of all, the wire system of the multi-wire EDM has been designed andanalyzed in detail. The three-wire roller reeling scheme is determined. As theoverall design scheme, the single tube for storing silk is determined. Maincomponents and parts of the wire system, mainly including multi-groove guidewheel and its components, fixture for supporting, have been designed. Theconduction mode has been also compared and selected. On the basis of the designof components, the structural analysis, sensitivity analysis and optimizationdesign has also been done. In order to determine whether the wire system canfunction properly in theory, its kinematic analysis was also carried out.Then, the feasibility of stable operation, stable discharge, and steady cuttingof the wire transport system was analyzed and verified through experiment. Afterthat, the discharge characteristics of multi-wire EDM were studied. Theprocessing efficiency experiment showed that the cutting efficiency of multi-wireEDM is higher than that of single-wire EDM under the same processingconditions. In order to grasp the laws of parameters selection of multi-wire EDM,this article also studied experimentally the influence of electric parameters on the main technical indexes of multi-wire EDM, mainly studied the influence laws ofpulse width, pulse interval, pulse peak current on the material removal rate, thekerf width and the surface quality.After that, this article studied experimentally the slice processing of SiCp/Alcomposites material using multi-wire EDM. First, the removal features ofSiCp/Al composites material using WEDM was studied. Because of SiC particles,the enhanced phase, the formation of discharge channel is blocked, so that theprocess is not very stable, characterized by open circuit, short circuit and arcphenomenon. Through observation and analysis of the surface morphology ofSiCp/Al composites material processed, it is concluded that the main form ofmaterial removal is melting and gasification of the substrate material, and theoverall flaking of the enhanced particles. The processing efficiency comparativeexperiment showed that the processing efficiency of Al is higher than that ofSiCp/Al composites, but the surface quality of Al processed is worse than that ofSiCp/Al composites, and the cause of this phenomenon was analyzed from theenergy perspective.In addition, this article also studied the variable thickness cutting of SiCp/Alcomposites material, and put forward the concept of slash interpolation angle.Slash interpolation feed can make the slice thickness of SiCp/Al compositesthinner, and through controlling the slash interpolation angle, the thickness of theslice can be controlled. Slice thickness and the slash interpolation angle is a kindof cosine relationship, which is verified by experiment, so as to make the slicethickness of SiCp/Al composites variable. In accordance with this law, theSiCp/Al composites sheet, the thickness of which is120.5μm, was cut out usingthe multi-wire EDM.Finally, the complete SiCp/Al slices were cut out using two-, three-, four-,five-wire WEDM respectively, the size of which is40mm×40mm, and theconsistency and uniformity of these slices have reached the pre-requirements.