This paper deals with micro turning of graphite by excimer laser. Excimer laser has the following characteristics. The wave length is less than 400nm in the range of ultraviolet rays, the pulse duration is about 10-20ns and the peak power reaches about several tens of MW, which lead to low heat damage to workpiece compared with that of YAG laser or CO
2 laser. Moreover, it is possible to form the various beam shapes by using the metal mask and reduction optical system. From the above mentioned viewpoints, excimer laser is used for fine precision machining for plastic, ceramic and so on. On the other hand, graphite is superior as an electrode material for EDM, and it has widely been used. However, it is difficult to make a fine complicated shape by traditional processing method because of its brittleness, especially in the case of thin plate less than 1mm. In this study, micro turning of graphite is experimentally investigated with KrF excimer laser and a micro lathe. Main conclusions obtained are as follows:
(1) It is possible to control the removal amount of graphite less than 1μm per pulse with KrF excimer laser.
(2) Various rotational symmetrical bodies can be formed by micro turning with trimmed excimer laser.
(3) The removal efficiency is higher when the irradiation direction of excimer laser is reverse against the rotating direction of workpiece, compared with the opposite case.
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