Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/1497
標題: 球銑切削力模型之研究
An Investigation on The Cutting Force Model for Ball End Mill
作者: 林明良
Lin, Ming-Liang
關鍵字: 球刀;球銑切削力;球銑切削力模擬
出版社: 機械工程學系
摘要: 
在金屬切削過程中,切削力的變化反映出加工表面的品質和刀具壽命等重要特性,因此扮演著相當重要的角色,隨著球銑在模具加工的應用,尤其是高轉速球銑在模具鋼之切削應用日趨普及,其切削特性更是值得深入探討。雖然一般端銑切削力的估算和預測的研究很多,但球銑刀因其外型與一般端銑刀有很大的差異,導致其切削特性與一般端銑有所差異,本文即針對球銑切削力特性進行研究。文中主要分成三部份探討球銑之切削力,第一部分探討球銑之切削力理論模式,針對球銑刀之刀刃運動路徑構成之瞬時切屑剖面積定義瞬時切削負載,並依此推導球銑之切削力。第二部份為規劃球銑之切削實驗,分別針對模具合金NAK80及6061鋁合金規劃高轉速球銑實驗,探討球銑參數對切削力之影響。第三部份則分析第二部分量測之切削力數據,據以計算切削力理論模式中之因子Kt之經驗公式和比例係數Kr及Ku,然後進行切削力模擬,結果顯示切削力Fx模擬之百分誤差介於10.3﹪至37.9﹪之間,最大值模擬誤差介於0.1~3.6N,最小值模擬誤差介於0.1~13.3N;而Fy模擬之百分誤差介於4.8﹪至15.8﹪之間,最大值與最小值模擬誤差分別介於0~12.9N與0.1~16.6N;至於Fz模擬之百分誤差則介於1.2﹪至16.7﹪之間,最大值與最小值模擬誤差分別介於2.8~7.0N與1.3~12.5N,此誤差大部分在實驗量測之標準差區間,顯示該球銑切削力理論模式尚稱合理。

The variation of cutting force in metal cutting reflects characteristics, such as the surface quality and tool life, of the cutting process; and therefore plays an important role in the cutting process. As the application of ball end mill on the machining of mold and die, in particular at high spindle rotation, becomes common, cutting forces of ball end mills deserve to be investigated. The force model of a ball end mill, however, differs from that of a regular end mill due to the difference on geometry. This thesis investigates the cutting forces of ball end mills, including the development of theoretical model, experiment design and excusion, and verification of theoretical model.
The theoretical cutting force model is based on the assumption that tangential cutting force is a function of instant cross-section of the chip, but not chip thickness used in most previous work. The instant cross-section, however, is computed via the path of tool. The second part is planning experiments of ball cutting .planning experiments of high rotational speed ball cutting of NAK80 and Al6061 individually .According to this planning ,we can confer the influence of ball cutting parameters and cutting force .The third part is analyzing the measuring data of the cutting force in the second part .According to the data to calculate Kt、Kr and Ku .And then to simulate cutting force .The result is that the percentage error of cutting force Fx is between 10.3% to37.9%.The maximum of simulation error is between 0.1 to 3.6 N ,and the minimum of simulation error is between 0.1 to 13.3 N; the percentage error of cutting force Fy is between 4.8% to15.8%.The maximum of simulation error is between 0 to 12.9 N ,and the minimum of simulation error is between 0.1 to 16.6 N; the percentage error of cutting force Fz is between 1.2% to16.7%.The maximum of simulation error is between 2.8 to 7.0 N ,and the minimum of simulation error is between 1.3 to 12.5 N .The most part of the error is in the standard error zone .of the experiment measuring .It means that the model of ball cutting force theory is reasonable.
URI: http://hdl.handle.net/11455/1497
Appears in Collections:機械工程學系所

Show full item record
 

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.