微銑削之修正切削力模型及微刀具壽命分析研究

The Study of Modified Micro-milling Force Model and Life Analysis for Micro End-mill

黃偉洲(Wei-chou Huang)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900260

摘要

影響微細切削精度的因素除機台靜動態精度外，還包括材料在微切削時的性質(最小切削厚度效應)、切削時微細刀具的振動與變形、刀具磨耗影響等因素。因此研究中將從推導微切削力模型著手，在考慮刀具振動、撓度變形、傾斜角、最小切削厚度效應及切削效率的條件下，發展微銑削加工參數優化技術。此外，研究中也將藉由分析刀具變形和磨耗型式，來建立微刀具壽命評估模式，以有效掌握刀具使用壽命，以便進行適當的加工規劃(如換刀時間、刀具磨耗補償等)及降低刀具磨耗造成的切削誤差。先進行微切削力模型及刀具動態行為分析研究，再來從事發展微刀具壽命評估模式及微銑削加工優化技術研究(含加工參數優化、換刀規劃與刀具磨耗補償)。研究中，採用投影面積積分法加入刀具傾斜角與最小切屑厚度推導出包含加工參數的微銑削力模型，進而利用實驗分析和有限元素模擬分析，分析驗證切削力對刀具變形及振動的影響，並建立預測模型，在考慮最小變形及最大加工效率下以決定最佳切削參數。另一方面，也採用Tylor所提出的刀具磨耗與壽命關係，進行實驗分析，進而找出適合精微銑削的刀具壽命評估模式。最後，則整合刀具壽命評估模式及加工參數優化技術，發展微銑削加工規劃模組，以提供加工者選擇最佳的刀具更換時間及刀具磨耗補償時間預測。

關鍵字

刀具壽命 ； 傾斜角 ； 微銑削 ； 最小切削厚度 ； 切削力

並列摘要

To enhance the implementation of micro milling, it is necessary to clearly understand the dynamic characteristics of micro milling so that proper machining parameters can be used to meet the requirements of application. Through calculating the instantaneous projection area of cutting, a new cutting force model of micro-milling was developed in this study. According to the instantaneous rotation trajectory of cutting edge, the cutting area projected to xy-plane was divided into three regions, and determined by rectangular integral method. Subsequently, the machining coefficients for a small axial depth of cut were experimentally investigated. Finally, the cutting force of micro-milling for different radial depth of cut and axial depth of cut can be accurately determined based on the proposed cutting force model. In the derivation, the effects of minimum chip thickness and the elastic deformation of material in the cutting area were taken into account. Micro-milling experimental results showed that the force model can be used for different micro milling processes. Comparing to the measured cutting force, the predicted cutting force had about 20%-30% errors.

並列關鍵字

minimum chip thickness ； rake angle ； tool life ； cutting force ； micro-milling

參考文獻

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