Tangential laser turning is applied to generate rotationally symmetric parts on a micrometer scale. Due to the non-contact material ablation, this process is especially advantageous for machining brittle materials such as stellite, which tends to easily break during conventional lathe. Furthermore, the use of focused ultrashort laser pulses enables the process to machine a large variety of materials because of the low heat input into the work piece. By impinging a cylindrical work piece laterally, a distortion of the projected circular, focused laser beam on the material surface occurs. In order to predict the actual fluence and intensity distribution on the rotating work piece, fundamental calculations and experimental results are necessary. Against this background, we report on laser turning of cylindrical components using ultrashort laser pulses with attention to the geometrical conditions and the resulting intensity distribution on the work piece. Particularly, the laser spot formation on a cylindrical surface at an oblique angle is discussed. In addition, the use of a trepanning optic in the laser turning process and the resulting beam path on the surface will be issued. The superimposed motion of the work piece rotation, trepanning rotation and linear laser feed rate is subject to fundamental calculations and experimental results.
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