电火花摇动加工高弹性合金双孔挠性薄壁的变形仿真分析

Simulation Analysis of Deformation in Double-hole Flexible Thin-wall with EDM Orbital Machining

针对3J33B高弹性合金在双孔挠性薄壁电火花摇动加工中出现的冲液导致薄壁变形和薄壁受热变形问题,进行了间隙流场电蚀产物运动仿真、冲液压力薄壁变形仿真和连续多脉冲放电薄壁受热变形仿真,初步设计了基于分步电火花摇动加工方法的双孔薄壁加工工艺路线。结果表明:电极自转速度对流场分布影响较大,转速增加有利于电蚀产物排出,机床摇动速度对流场分布影响较小;冲液可改善小孔的入孔质量,但对于深小孔加工,电蚀产物的排出作用有限;薄壁变形量与冲液压力呈现正相关趋势,在冲液压力为10 MPa时,薄壁变形为0.423μm,冲液压力对薄壁变形影响较小;薄壁变形量基本随着峰值电流和脉宽的增加而增大,而脉间对变形影响较小,热变形的影响大于冲液压力引起的变形影响。

Aiming at the problem of thin-wall deformation by liquid impact and thin-wall thermal deformation of high-elastic alloy 3J33B in EDM,the simulation of particle movement in gap flow field,thin-wall deformation with flush pressure and thin-wall thermal deformation with multi-pulse discharge were carried out,and the processing route of double-hole flexible thin-wall EDM based on step-by-step EDM orbital machining was designed.The simulation results show that rotational velocity of electrode has a great influence on flow field distribution,increasing the speed can promote the removal of electro-erosion products,and the orbital velocity of machine tool has little influence on flow field distribution.Flushing can improve the quality of hole entry,but the removal of electro-erosion products of deep small holes is limited.The deformation has a positive correlation with the flushing pressure,when the flushing pressure is 10 MPa,the deformation of thin-wall is 0.423μm,and the flushing pressure has little effect on the deformation,the deformation basically increases with the increase of the peak current and pulse duration,and the pulse interval has little effect on deformation.The effect of thermal deformation is greater than the effect of deformation caused by the flushing pressure.