Experimental Study of Plused arc Machining for Superalloy GH4169

Abstract

Abstract. Pulsed arc machining can be used to process the difficult-to-machining materials such as nickel base superalloy with high efficiency, but the surface processing quality is not unsatisfactory. To improve the processing quality, surface micro topography, recast layer were observed in the pulsed arc machining of GH4169 superalloy, surface roughness and microhardness has been tested herein. The results shows that processing parameters in duty cycle at 15~55%, pulse frequency at 400 ~ 700HZ achieved surface roughness lower than 25μm. The recast layer that generated in process result in work harden within 0~50μm from the surface. Cracks were easily formed by high frequency and duty cycle, the increased thickness of recast layer formed by low frequency. The machining quality can be improved by reasonable parameters selected.