Scalability of Tool Path Planning to Micromachining

Micromachining applications have received increased emphasis in recent years with the advent of new precision manufacturing applications which have stringent requirements for surface and edge finish. One of the main concerns in mi- cromachining is burr formation which can incur high production costs due to time-consuming deburring operations. Although deburring operations are commonly carried out in macroscale milling, in micro machining they can be difficult to use. De- burring processes can destroy delicate microfeatures and are usually unfeasible at the micro scale. For this reason, the utiliza- tion of burr minimizing machining tool paths is desirable. Optimum tool paths minimize burr formation while satisfying sur- face quality requirements, dimensional tolerances, and cycle time constraints. A new concept for micro end milling tool paths is developed. An integrated performance index using the Taguchi method is introduced to optimize the main microscale end milling process outputs: surface quality, edge accuracy, burr formation, and time constraints. In addition, the concept is ap- plied to macroscale milling and its scalability down to the micromilling scale is studied.