Abstract:A8 tool steel is a hard-to-machine material with high hardness and high toughness, which is usually processed by WEDM. In the actual production process of WEDM processing A8 tool steel, the surface roughness and material removal rate are important indicators of surface quality and processing efficiency respectively, and the discharge parameters directly affect the surface roughness and material removal rate. Under the conditions of adopting several groups of commonly used discharge parameters such as machining current, pulse width and pulse gap, the A8 tool steel was processed, the specific influence rules of each discharge parameter on surface roughness and material removal rate were obtained respectively. The results show that with the increase of processing current, the surface roughness and material removal rate of machined materials increase simultaneously and the trend is similar; with the increase of pulse width, the surface roughness and material removal rate increase simultaneously; with the increase of pulse interval, the material removal rate decreases, and the surface roughness decreases in the early stage.The decreasing trend slows down after the pulse interval is 8 μs, the minimum is reached when the pulse interval is 10 μs, and increases slightly after the pulse interval is more than 10 μs with little change. The research results provide a technical reference for WEDM processing A8 tool steel in actual production, and suitable combination of discharge parameters can be selected according to different production requirements