本研究中提出了一種以最佳化方法對於刀具磨耗控制和切削參數調整的概念。刀具磨耗控制是金屬切削過程中的重要問題，嚴重的刀具磨耗導致較差的表面品質和較高的機台負載，從而降低了產品品質和切削效率，因此當刀具磨損達到標準時，必須更換切削刀具。在大多數刀具磨耗研究中，切削參數（例如切削速度和進給率）都在探討如何運用可行的參數範圍以減少刀具磨耗，但是實際上要被加工的零件差異很大，因幾何造型造成刀具與工件之間的接觸面積不斷變化，切削速度和進給率在拐角處會進行調整以避免突然地改變而超過刀具負荷，故以同樣的切削條件不太可能適合加工具有不同幾何形狀的零件。另外材料移除量因工件而異，對於大型產品，期望刀具壽命剛好為操作時間，並且不應在完成一項操作之前更換切削工具。基於這些考慮，提出了一種最佳化切削參數的方法。在這項研究中，成本函數包括加工成本和刀具磨耗損失。每次操作後記錄加工時間和刀具磨耗作為最佳化方法的輸入。經過多次疊代後，可以達到零件的最佳切削速度和進給率。
在本文中介紹了兩個案例研究，由案例的結果可以看出共軛梯度法應用於最佳化成本的方法能夠提供有效的資訊使操作人員選取適合的車削參數，達到降低總加工成本以及操作後刀具磨耗將接近刀具壽命的目的，使切削效益及生產率提升。

A novel concept of tool wear control and cutting parameters tuning is proposed in this study. Tool wear control is an important issue in metal cutting processes. The tool wear results in worse surface quality and higher machine loading, which reduce the product quality and the cutting efficiency. Therefore, the cutting tools must be replaced when the tool wear reaches the criteria. In most of the tool wear studies, the cutting parameters such as cutting speed and feed are considered to investigate the feasible range to minimize the tool wear. However, the parts to be machined vary dramatically in reality. It is not possible to machine parts with different geometry using constant cutting conditions. The contact area between the cutting tool and the workpiece changes continuously. The cutting speed and feed are adapted at the corners to avoid sudden change of tool loading. In addition, the amount of material to be removed is different from part to part. For a large product, a longer operating time is expected, and the cutting tool is not supposed to be changed before one operation is finished. According to these considerations, an optimization method of tuning cutting parameters is proposed in this study. In this study, the cost function includes the machining cost and the loss of tool wear. The machining time and the tool wear were recorded after each operation as the input for the optimization algorithm. The optimized cutting speed and feed rate of a part can be approached after a number of iterations. With these cutting parameters, the tool wear is expected to be close to the end of the tool life after the operations with relative lower cutting cost. Two case studies of turning is presented.

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