| 摘要: | 二氧化鋯陶瓷具有硬度高、耐高溫、耐磨耗、抗腐蝕等特性，屬不易加工之硬脆材料，於進行傳統機械微孔鑽削加工時，螺旋鑽針會因磨耗過大導致切削力急遽的增加，從而使微孔入、出口周圍易產生大面積且不規則的脆裂情形，必須加以克服。本研究是利用超音波振動輔助啄鑽式加工方法，針對二氧化鋯陶瓷材料進行微孔鑽削加工之研究，並探討於各種鑽削加工方式與參數條件下如進給速度、啄鑽量、超音波功率及主軸轉速等，對微孔鑽削加工後材料品質特性的影響，而材料品質特性包含有微孔入、出口破裂面積值、刀具切削刃圓角變化量以及實際微孔平均孔直徑值。微孔鑽削加工實驗後，係以光學顯微影像量測儀（OM）對微孔入、出口周圍破裂形貌進行觀察，再以雷射共軛焦掃描顯微鏡（LSCM）進行微孔入、出口處破裂面積與實際微孔平均孔直徑之量測，最後利用掃描式電子顯微鏡（SEM）微觀分析微孔出口處破裂形貌與加工後螺旋鑽針切刃形貌。實驗結果顯示，超音波振動輔助啄鑽式加工方法，可以有效的排除鑽削過程中的切屑與加工熱能，從而減少加工時所產生的切削力，達到降低螺旋鑽針磨耗與獲得較佳的微孔品質，根據實驗結果，於進給速度0.15 mm/min、啄鑽量15 μm、超音波功率等級Level 2以及主軸轉速9000 rpm之較佳加工參數組合下，可獲得較小的微孔入口破裂面積16328.06 μm²以及較小的微孔出口破裂面積24951.72 μm²，相較於傳統的機械鑽削加工方法，微孔入口破裂面積值減少了48.99 %，而微孔出口破裂值減少87.73 %，且實際微孔平均孔直徑值及螺旋鑽針切削刃圓角變化量也都得到了改善。;Zirconia ceramics possess characteristics such as high hardness, high temperature resistance, wear resistance, and corrosion resistance, making them hard and brittle materials that are difficult to process. During traditional mechanical micro-drilling, spiral drill bits suffer from excessive wear, leading to a rapid increase in cutting force. This results in large, irregular fractures around the micro-hole entrances and exits, which need to be addressed. This study employs an ultrasonic vibration assisted pecking drilling method to conduct micro-hole drilling on zirconium dioxide materials. It explores the effects of various drilling methods and parameter conditions, such as feed rate, pecking depth, ultrasonic power and spindle speed on the quality characteristics of the drilled micro-holes. These quality characteristics include the chipping area at the inlets and outlet, variation of arc radius of the drill bit and the average hole diameters. After the micro-drilling experiments, an optical microscope (OM) was used to observe the chipping morphology around the micro-hole inlets and outlet. A laser confocal scanning microscope (LSCM) measured the chipping area and the average hole diameters. Finally, a scanning electron microscope (SEM) conducted a micro-analysis of the fracture morphology at the micro-hole outlet and the cutting edge morphology of the drill bits post-machining. The experimental results show that the ultrasonic vibration assisted pecking drilling method effectively discharges chips and machining heat during the drilling process, reducing the cutting force and thereby decreasing drill bit wear and improving micro-hole quality. According to the experimental results, an optimal parameter combination of 0.15 mm/min feed rate, 15 μm pecking depth, Level 2 ultrasonic power, and 9000 rpm spindle speed achieved a smaller micro-hole chipping area of 16328.06 μm² at the inlet and a smaller micro-hole chipping area of 24951.72 μm² at the outlet. Compared to traditional mechanical drilling methods, the micro-hole inlet chipping area was reduced by 48.99%, and the micro-hole outlet chipping area was reduced by 87.73%. Additionally, improvements were observed in the average hole diameter and the variation of arc radius of the drill bit. |
