磁力輔助內圓孔螺旋研拋加工之研究

The study on magnetic-assisted spiral polishing of inner wall of bores.

曹嫚津(Man-Chin Tsao)

指導教授 ： 顏炳華

國立中央大學/工學院/機械工程學系/碩士(2011年)

摘要

本實驗之研究是利用一螺桿旋轉驅動碳化矽與磁性熱熔膠粒磨料，並在工件外圍增置一強力磁鐵，磨料內的磁性熱熔膠粒受到磁鐵吸引，擠壓碳化矽磨粒對工件內圓孔表面的螺旋研磨拋光。藉由控制磁通量密度、碳化矽粒徑、碳化矽重量、磁性熱熔膠粒重量、矽油黏度、主軸轉速、加工時間和加工間隙等加工參數，探討對1.工作溫度、2.磨料黏度、3.表面粗糙度與4.材料去除率的影響，並找出最佳參數組合；同時亦觀察實驗後，各加工參數對工件表面形貌之影響。
由實驗結果顯示，隨著加工時間的增加，磨料會呈現良好的流動性，此特性有利於精微之螺旋研拋，使達成理想之表面精拋效果。而選用磁通量密度90mT的磁鐵、粒徑22μm、重量120g的碳化矽磨粒、黏度2000mm2/s的矽油、加工轉速4000rpm和加工間隙6mm可獲得最佳的表面改善效果，有效的將工件表面粗糙度從0.9μm降至0.094μm。

關鍵字

磁力輔助螺旋研拋加工 ； 內孔拋光 ； 磨料流動加工

並列摘要

The study is on the spiral polishing of the inner wall of bores through abrasive flow by means of the grinding materials of silicon carbide and magnetic hot melt particles, propelled by a spiral spindle and a circular neodymiμm magnet around the work piece. The neodymiμm magnet functioned as driving the magnetic hot melt particles and forcing the silicon carbide to polish the inner surface of bores. In the experiment, the factors investigated included the effects upon working temperature, abrasive viscosity, surface roughness, material removal by controlling magnetic flux density, size of silicon carbide particles, weight of silicon carbide particles, weight of magnetic hot melt particles, silicone oil viscosity, spindle rotation speed, machining time, and machining gap. In addition, sets of polishing parameters on the polished surface were examined to find the best parameter setting.
The result of the experiment suggested that with the increase of machining time, the liquidity of abrasive rose, and a more ideal polishing effect could be achieved. Based on the results, the best polishing effect might be obtained through the use of a 90mT neodymiμm magnet, 22μm SiC particles, 120 grams of SiC particles, 2000mm2/s viscosity of silicone oil, 4000rpm rotation speed, and a 6mm-machining gap. The surface roughness was effectively improved from Ra 0.9μm to Ra 0.094μm.

並列關鍵字

spiral polishing ； abrasive flow finishing ； magnetic-assisted spiral polishing ； the polishing of inner wall

參考文獻

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