臺灣大學: 機械工程學研究所廖運炫李庚翰Lee, Keng-HanKeng-HanLee2013-04-012018-06-282013-04-012018-06-282010http://ntur.lib.ntu.edu.tw//handle/246246/256214本研究利用微銑削平面加工探討切削刀紋之成因及改善的方法，刀具路徑粗加工後，表面會殘留刀具路徑留痕高，欲以較細微之刀具路徑節距去除留痕高，會殘留細微之刀紋。經由衝擊共振實驗以及頻域分析，發現刀紋之成因與結構特性及偏擺量無關，推測刀紋成因應為部份材料被推擠犛切以及產生彈性變形無法被刀具去除而成。本研究加工黃銅合金和純鎳，加工黃銅合金每刃進給量至0.4μm/flute以上；刀具皆可有效切削除去表面刀紋，由於純鎳抵抗塑性變形能力較佳，每刃進給量需提昇至0.8μm/flute以上才可去除表面刀紋。過小之進給量使得切削表面材料有被推擠之現象，可得切削刀紋成因為刀具犛切材料而形成，但提高每刃進給量使得切削力變大，表面粗糙度變差。以水基切削液進行加工，可發揮較佳之潤滑性降低切削力，與其他切削環境比較之下，在不同進給量皆可得到較好之表面粗糙度，使用水基切削液，可使每刃進給量較低時，切屑較易流動，工件材料可順利被去除，有效改善一般低進給下的切削刀紋，在每刃進給量為0.16μm/flute加工黃銅合金時，表面粗糙度Ra僅有0.026μm，且表面未具有切削刀紋。An experimental investigation on the reasons of surface texture, and the improvements of this phenomenon by flat surface micro-milling was conducted in this study. After rough machining, marks on the surface caused by scallop height, can be eliminated by using small pitch of tool path. But some slight textures on the surface still remain. By impact test and frequency domain analysis, it was found that the reasons of surface textures were little related with dynamic characteristics of machine tool structure and tool runout. Brass and pure nickel was machined in this study. Surface textures can be effectively eliminated when feed raises to 0.4 and 0.8μm/flute in brass and pure nickel machining, respectively. The reason of textures is that the partial material was plowed and elastic deformation occurred. Hence the material was not able to remove by cutting tool in a low feed. But unpreventablely, raising feed causes bad surface roughness. Adding water base fluid during the machining process can obtain better surface roughness whether the feed is high or not, even in a very low feed which the condition is good for the surface texture. According to the result, the feed of 0.16μm/flute is adopted in brass machining, and the good surface roughness Ra, which is only 0.026μm, can be obtained without appearance of surface texture.6859423 bytesapplication/pdfen-US刀紋微銑削犛切每刃進給量水基切削液surface texturemicro milling,plowingfeed per flutewater base fluidthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/256214/1/ntu-99-R97522701-1.pdf