高速銑削304不銹鋼薄板之特性探討

An Investigation on the Characteristics of 304 Stainless Steel Thin Plate in High Speed Machining

鄭中智(Chung-Chih Cheng)

指導教授 ： 簡文通

國立屏東科技大學/工學院/機械工程系所/碩士(2010年)

https://doi.org/10.6346/NPUST.2010.00240

摘要

本研究的目的是在高速銑削不銹鋼薄板工件時，探討顫振頻率與表面粗糙度之關係，及自行開發防止薄板變形夾具之改善效果。首先設計製作出用以防止薄板在高速銑削時發生翹曲或變形之夾具。接著探討高速切削理論應用於薄板工件加工之可行性，利用選擇合適的銑削參數防止顫振發生以確保工件之尺寸精度及表面粗糙度。並建立顫振頻率與表面粗糙度之關係式。研究的程序為在銑削進行前選用不同的主軸轉速為銑削參數，在銑削操作後量測薄板的表面粗糙度，在銑削進行時則利用量測顫振儀器收集因顫振所產生之顫振頻率。實驗結果用來建立顫振頻率與表面粗糙度之關係式，並探討主軸轉速對表面粗糙度與顫振頻率之影響性。結果顯示使用自行開發之夾具在薄板銑削對變形量之影響，本研究所設計之夾具在實際量測下改善70~80%，達到防止薄板變形之效果。就表面粗糙度之影響，所設計之夾具在主軸轉速10000rpm至14000rpm得到較好的表面平均粗糙度(Ra)，範圍在0.38μm~0.45μm，在主軸轉速9000rpm至12000rpm得到較好的表面最大粗糙度(Rmax)，範圍在2.3μm~3.3μm。就顫振頻率之影響，薄板銑削的切削訊號振幅比夾具薄板銑削的切削訊號振幅來的高，證明所設計之夾具在高速銑削不銹鋼薄板製程上有改善。在本研究有系統的探討高速銑削不銹鋼薄板時找出顫振頻率對表面粗糙度之影響，並建立顫振頻率與表面粗糙度的關係式，其根據顫振頻率與表面平均粗糙度(Ra)關係式之驗證其平均誤差率3.63%，顫振頻率與表面最大粗糙度(Rmax)關係式之驗證其平均誤差率7.85%。研究成果可供高速銑削不銹鋼薄板之製程改善之參考。

關鍵字

高速銑削 ； 不銹鋼薄板 ； 顫振頻率

並列摘要

The purpose of this research is to investigate the relationship between chatter frequency and surface roughness and the effect of a new developed fixture for preventing deformation in high-speed milling stainless thin plate. Firstly, a fixture for preventing warping or deformation of a thin plate when high-speed milling is designed and fabricated. An investigation based on a high-speed cutting theory is performed to understand the feasibility for thin plate milling. In order to ensure the accuracy of dimensions and surface roughness, the milling parameters are selected. To prevent the occurrence of flutter. Then a relationship between chatter frequency and surface roughness of workpiece is established. The procedure in this research is to choose a series of spindle rotating speed before carrying out experiments, to measure surface roughness after a milling operation and to collect signals generated due to vibration by an accelerometer during performing a milling operation. The results are used to build a relationship between chatter frequency and surface roughness of workpiece. The influence of spindle rotating speed on chatter frequency and surface roughness has also been explored. It is shown that a reduction of 70% to 80% for improving deformation by using a self-developed fixture is achieved. For the effect on surface roughness, a better average surface roughness(Ra)0.38 to 0.45μm is found in the spindle speed range 10,000 to 14000 rpm, and a between maximum surface roughness(Rmax)2.3 to 3.3μm is obtained. It is also shown that a higher signal amplitude can be found when operating a milling process without the developed fixture. By conducting a systematic study, a relationship between flutter frequency and surface roughness has been established. The error for the average surface roughness. (Ra) obtained. From predicting values by using the relationship compared with the results performed, by verification experiments is 3.63%; while for the maximum surface roughness(Rmax) is 7.85%. The research results is proved that can be used for reference in high-speed milling stainless thin plate.

並列關鍵字

High-speed milling ； Stainless thin plate ； Chatter frequency

參考文獻

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