SURFACE TREATMENT METHOD AND SURFACE TREATMENT DEVICE

To inhibit unevenness from being unintentionally caused in a processed portion when surface treatment is performed to a discoid processing object by electro-discharge machining.SOLUTION: A processing electrode 30 forming a circular shape in a plan view and having an outer diameter larger than or equal to an outer diameter of a processing object is disposed above the processing object so as to overlap with the processing object partially in the plan view. The processing object is rotated around a first center axis X1 and the processing electrode 30 is rotated around a second center axis X2. Then, an electrical current is discharged between the processing electrode 30 and the processing object in a state where both of the processing object and the processing electrode 30 are rotated.SELECTED DRAWING: Figure 5 【課題】円板状の加工対象物を放電加工により表面加工する際に、意図せずに加工箇所に偏りが生じることを抑制する。【解決手段】平面視円形状をなしかつ外径が加工対象物の外径以上である加工電極３０を、平面視で、加工対象物と部分的に重複するように、加工対象物の上側に配置し、加工対象物を第１中心軸Ｘ１周りに回転させ、加工電極３０を第２中心軸Ｘ２周りに回転させ、加工対象物及び加工電極３０の両方が回転した状態で、加工電極３０と加工対象物との間で放電する。【選択図】図５