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Optimization of toolpath with circular cycle transition for sharp corners in pocket milling

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The toolpath for a sharp corner is important in pocket machining during high-speed machining with numerical control. When milling a sharp corner, a longer tool engagement length generates larger engagement angle and milling force, which reduces the machining precision. To reduce the milling force at a sharp corner and clear up uncut materials, the toolpath at corners must be optimized. In this paper, a new method of generating the toolpath with circular cycle transition at a sharp corner is put forward to provide a new numerically controlled toolpath pattern for pocket milling. On the basis of a common contour-parallel toolpath, minimum radius arcs and circular cycles are added in sequence at a sharp corner. When the cutter comes to the sharp corner, the corner material is removed step by step with a sequence of circular cycles. The validity of the proposed method is confirmed through simulation and tests. The proposed toolpath method is realized by employing the Institute of Manufacturing Technology (IMT) computer-aided manufacturing (CAM) system. The toolpaths at sharp corners generated through commercial software and IMT-CAM software are tested by comparing the corresponding milling forces. It is illustrated in the results that the proposed method reduces the milling force effectively and is of great significance when it is applied in high-speed machining.

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Correspondence to Cheng Yong Wang.

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Wu, S., Zhao, Z., Wang, C.Y. et al. Optimization of toolpath with circular cycle transition for sharp corners in pocket milling. Int J Adv Manuf Technol 86, 2861–2871 (2016).

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  • Sharp corner
  • Toolpath
  • High-speed machining
  • Circular cycle