超音波加工( Ultrasonic micro machining, USM )，被認為是在脆性材料上製 作微細結構及鑽孔非常準確且有效率之方法。本文主要研究超音波加工法在脆性 材料上製作微細結構之可行性。脆性破壞是超音波加工中主要的材料去除機制， 若沒有好好控制其加工參數則會造成較差的表面粗度及較深的裂痕。為了確保得 到較佳的表面品質和改善其加工效率，我們試著從加工機制、表面完整性及刀具 磨耗等加工參數中找出其相關性。本實驗已探討加工參數如磨粒種類、磨粒粒徑 和進給率對其加工的影響，發現利用由粗而細加工的多道次加工法，可得到較佳 的表面完整性，並可兼顧其加工效率。本研究已成功的在玻璃、玻璃陶瓷、熔石 英和矽等不同的脆性材料上加工出直徑小於100 μm且表面粗度Ra小於150 nm的 幾何微結構。 Ultrasonic micro machining (USM) is considered to be a very accurate and relatively effective method to engrave fine patterns and drill holes on brittle materials. This research is mainly concerned on the investigation of the feasibility of utilizing UM technique to fabricate microparts from brittle materials. Although brittle fracture (micro chipping) is the dominant material removal mechanism occurred during u-UM process, however, if the machining parameters are not properly controlled, it results in poor surface roughness and deep penetrated crack. In order to ensure a better surface quality and improve the machining efficiency, efforts have been made trying to correlate the material removal mechanism, surface integrity and tool wear involved in the u-UM process to the machining conditions. This experiment studied the effect of machining parameters such as types of abrasives, grit sizes and feedrate on the u-UM process. It was found that by dividing the machining process into several stages, from course to fine, a better surface integrity can be achieved without surrendering too much efficiency. Micro-components of various brittle materials such as glass, Zerodur, fused quartz and si with dimension smaller than 100 um and surface roughness better than Ra 150nm have been successfully fabricated in this study.
