Research on the Surface Quality of the Blasting Erosion Arc Machined Stainless Steel

The Blasting Erosion Arc Machining (BEAM) process is a novel process to efficiently remove the difficult-to-cut materials. Preliminary experiments show that the quality of the machined surface is influenced by the processing parameters including the discharge energy, flushing pressure and discharge polarity. In this paper, a 3-factor, 2-level full factorial experiment was conducted to investigate the influence of the processing parameters on surface roughness with BEAM of stainless steel. The experimental results show that the surface roughness increases with the raising peak current and pulse duration, and declines with the raising flushing pressure. Furthermore, a set of comparative experiment was designed to evaluate the integrity of the stainless steel surface machined with positive and negative polarity BEAM. The experimental results indicated that the negative BEAM results in a rough surface and the Ra was up to 55 μm, the heat-affected zone was about 13 μm and the recast layer was detected. On the contrast, positive BEAM could achieve a better surface and the Ra was less than 9.5 μm, the heat-affected zone was less than 5 μm and the recast layer was scarcely seen. In addition, comparing with negative BEAM, the positive BEAMed surface was smoother and brighter.