形彫り放電加工では，放電が加工液中に浮遊する導電性をもrnつ加工屑を介して生じるため，不均一な加工屑濃度の分布に伴rnいギャップ分布が不均一になる．また，シャープなエッジを持rnつ工具電極で加工を行う場合，エッジ部やコーナ都は工具電極rn面上の単位面積当たりの放電頻度が平坦部より多くなり，消耗rn体積も多くなるため角ダレが生じ加工前の電極形状を正確に工rn作物に転写できないなどの問題がある．そこで，不均一なギャrnップ分布や電極消耗を予測することで，加工後の所望の工作物rn形状を得るのに必要な電極形状の設計が行なえる形彫り放電加rn工シミュレーションの開発が要望されている．%This paper describes a die-sinking EDM simulation which can simulate the wear of tool electrode with sharp edges and the distribution of debris particles concentration in the machining gap. This simulation is based on the discharge location searching algorithm to reproduce the gap phenomena caused by every pulse discharge. The algorithm is a simple repetition of the routine which is composed of: 1) determining the next discharge location, 2) removing the tool electrode and work piece electrodes, 3) distributing debris particles, and 4) feeding the tool electrode. This algorithm was modified to simulate the removal of surfaces with large inclination, lateral surfaces and edge portions of the tool electrode. Moreover, a method to calculate the debris particles concentration in the gap extended three dimensionally was developed. Thus, the wear of tool electrode with sharp edges was simulated combining the discharge location searching algorithm with the 3D calculation of debris concentration. Simulation results agreed with experimental results especially in the case of using brass as the tool electrode material with which deposition of carbon on the tool electrode is negligibly small.
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