High efficiency blasting erosion arc machining of 50 vol.% SiC/Al matrix composites

Abstract

Blasting erosion arc machining (BEAM) is adopted to improve the machining efficiency of high fraction (50 vol.%) SiC/Al matrix composites. Results of the fractional factorial experiments and full factorial experiments indicate that the electrical parameters (peak current, pulse duration and pulse interval) are the main impact factors of the machining efficiency, and when the peak current is 500 A, the pulse duration is 8 ms and the pulse interval is 2 ms, the material removal rate reaches to 6000 [Formula: see text]/min. Furthermore, the material removal rate was optimized and could be as high as 7500 [Formula: see text]/min with the tool wear ratio about 10%. Simulation of the single discharge heat transfer illustrates that the SiC particles have negative influence on the machining performance due to their temperature dependent characteristics. The polarity effect was also studied and it is disclosed that different machining polarities have different influences on the machining performance, surface integrity and even the formation of SiC particles. Finally, a 50 vol.% SiC/Al workpiece was machined with blasting erosion arc machining.