Research On Processes Of Precision EDM Of Cavity For High Volume Fraction SiCp/Al

SiCp/Al composites as a studied kind of popular material has been used widely in the aerospace,electronic instrumentation, automotive and other fields, because of its higher specific stiffness andstrength, high thermal conductivity and good dimensional stability. An especially high volumefraction SiCp/Al composite is the ideal choice for high power density electronic packaging shellmaterial. Due to the presence of reinforced refractory SiC particles in SiCp/Al composites, it isdifficult to machine with traditional processing methods.EDM method removes mainly the workpiece material by galvanic action; the workabilitydepends on the thermal properties of materials, and has nothing to do with its basic mechanicalproperties. Therefore, EDM method is a good way to high volume fraction SiCp/Al compositesprocessing, has high academic value and practical value of the research process.In this paper, SiCp/Al composites of the65%SiC volume fraction were used as test materials,and processed by Spain ONA DB300EDM machine tools for the EDM experiment. First of all, Onthe basis of single factor experiments, the impact of the several major discharge parameters on processindicators of high volume fraction SiCp/Al composites was explored. as well as the negative, narrowwidth optimum electrical parameters combinations was summarized.Then, the order of the electricalparameters respectively affecting process indicators was acquired through range analysis byorthogonal experimental design, and the electrical parameters include the open circuit voltage, thepeak current, pulse width, pulse gap, capacitance and gap voltage,as well as process indicatorsinclude processing efficiency, electrode wear, unilateral gap, the surface roughness. Under theguidance of the theory of gray, the optimal combination of electrical parameters regimen forintegrated a number of process indicators was obtained by the gray correlation method. Finally, inconsideration of applications of TR shell component packaging in the high volume fraction SiCp/Alcomposites, the processing was carried out to explore examples of machining ladder cavity in twoway of electrode design. Compared with the way of integral electrode, the way of decompositionelectrode can be better processing results.