为避免回转对称微结构光学模具加工中产生的毛刺、尖角缺损及表面划痕，提出一种基于超精密切削的B轴旋转加工工艺。通过实验研究加工路径、切削速度、B轴旋转速度及切深等影响微模具面形精度和表面质量的主要因素，优化切削轨迹规划与加工参数，开展了2种微结构模具的加工实验，得到尺寸精度小于1.4 μm、表面粗糙度小于14 nm的结构完整性较好、表面无划痕的模具。实验结果验证了回转对称微结构光学模具B轴旋转加工工艺的可行性。
A B axis rotating machining process based on ultra-precision cutting was developed to prevent burrs, sharp corner defects and surface scratches when machining microstructured optical molds with rotational symmetry. The form accuracy and surface quality of the molds were mainly influenced by the machining path, cutting speed, B axis rotating speed and cutting depth. Tests of these factors were used to optimize the cutting trajectory planning and machining parameters. Two microstructured molds were constructed with no sharp corner defects and no surface scratches, dimensional accuracies of 1.4 μm and surface roughnesses better than 14 nm. The results show the feasibility of the B axis rotating machining process for cutting microstructured optical molds with rotational symmetry.
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