The Development of Surface Profile Models in Abrasive Slurry Jet Micro-machining of Brittle and Ductile materials

In low-pressure abrasive slurry jet micro-machining (ASJM), a slurry jet of fine abrasive particles is used to erode micro-sized features such as holes and channels in a variety of brittle and ductile materials with a high degree of accuracy and repeatability without the need for a patterned mask. ASJM causes no tool wear and thermal damage, applies small forces on the workpiece, allows multilevel etching on a single substrate and is relatively quick and inexpensive. In this study for the first time, the mechanics of micro-slurry jet erosion and its relation to the fluid flow of the impinging jet was investigated using a newly developed ASJM system. Existing surface evolution models, previously developed for abrasive air jet machining (AJM), were evaluated and modified through the use of computational fluid dynamic (CFD) models for profile modeling of micro-channels and micro-holes machined with ASJM in brittle materials. A novel numerical-empirical model was also developed in order to compensate for the shortcoming of existing surface evolution models and provide a higher degree of accuracy in predicting the profiles of features in ductile materials machined with ASJM. In addition, the effect of process parameters on the minimum feature size attainable with ASJM as a maskless process was also examined and it was shown that the size of machined features could be further reduced.Ph.D