放电参数对线切割加工A8工具钢表面粗糙度与材料去除率的影响

Effect of Discharge Parameters on Surface Roughness and Material Removal Rate of A8 Tool Steel by WEDM

A8工具钢是一种高硬度高韧性的难加工材料,常用电火花线切割来加工处理。电火花线切割加工A8工具钢实际生产过程中,表面粗糙度和材料去除率分别是加工表面质量和加工效率的重要指标,放电参数直接影响到表面粗糙度和材料去除率。在几组生产中常用的放电参数(加工电流、脉冲宽度、脉冲间隙)条件下,加工A8工具钢,分别得到每种放电参数对表面粗糙度和材料去除率的具体影响规律,结果表明:随着加工电流的增大,加工后材料表面粗糙度和材料除去率同时增大且趋势相似;随着脉冲宽度的增大,加工后材料表面粗糙度和材料除去率同时增大;随着脉冲间隙的增大,材料除去率呈递减趋势,加工后材料表面粗糙度前期递减,在脉冲间隔8μs后减小趋势放缓,在脉冲间隔10μs时达到最小值,在脉冲间隔大于10μs后略有升高,变化幅度不大。研究结果为实际生产中电火花线切割加工A8工具钢提供技术参考,可以根据不同的生产要求选择合适的放电参数组合。

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 8μs,the minimum is reached when the pulse interval is 10μs,and increases slightly after the pulse interval is more than 10μs 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.