半圓球形曲面之最佳五軸銑削參數研究

Study on Five-Axis Machining Parameters for Semi-Spherical Surface

黎俊緯(Chun-Wei Li)

指導教授 ： 陳政順 ； 蔡哲雄

國立臺北科技大學/機電學院/機電整合研究所/碩士(2008年)

摘要

半圓球形曲面應用於許多設計上，如監視攝影機之球罩，其精度取決於模具之品質。本研究探討五軸加工機銑削半球形模具的最佳化切削參數，以提升工件之表面品質與精度，並進一步降低成形後之處理成本。實驗的參數主要為刀具傾斜角度、表面切削速度、銑刀每刃進給及軸向切削量四個相關控制因子；量測各個工件切削後表面粗糙度與真圓度，使用灰色田口法以求得最佳加工參數組合。在本次實際研究中，真圓度品質特性採用望小特性，而表面粗糙度品質特性則是採用望目特性；四個控制因子各設定了三個水準，水準的設定考慮了刀具干涉、機台性能及刀具型錄建議數值。實驗機台為床台旋轉型之五軸加工機，加工材料為模具鋼NAK80。實驗結果顯示，依本研究所得到之最佳切削參數加工，凹半球面真圓度

關鍵字

五軸加工 ； 製程參數最佳化 ； 球形曲面 ； 模具加工

並列摘要

The semi-spherical surface applies in many regions, such as the mask of security camera. The precision of surface is depended on the quality of mould. In order to improve the surface quality and accuracy of workpiece and reduce the manufacturing cost, we design an experiment to optimize the roughness and roundness of 5-axis machining center machining a semi-spherical mould. In our case, the four parameters are tool tilt angle, surface cutting speed, feed per tooth, and axial cutting depth. Use the Gray Taguchi method to find the optimal machining parameters. The target of experiment of roughness is nominal-the-best, and the aim of experiment of roundness is smaller-the-better. And each of the four factors has three levels which consider the tool interference, the capability of machine center, and the recommendation of tool’s catalog. The table rotating-tilting type five-axis machine is used for this study, and the material of die is NAK 80 mould steel. Primary, at this time, the experimental result shows that, the best roundness of the concave mould and convex mould are 0.022 mm and 0.026 mm, and the best surface roughness of the concave mould and convex mould are 0.47μm and 0.49μm respectively, based on the optimal parameters found in this study.

並列關鍵字

Five-axis machining, Parameter Optimization ； Spherical surface ； Mould machining

參考文獻

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