MicroMachining

At this time, unfortunately, a convergence in terminology has not been forthcoming and, hence, a definition of the term Micro-Machining to be implied in the context of this assessment is in order. In principle, one may take two viewpoints:(1) The first viewpoint may define Micro-Machining as the collection of all cutting operations that are performed on micro/meso-scale components and products that fall into the 100 μm to 10,000 μm size range as shown in the figure below. The Micro-Machining regime is characterized by the requirement of producing high accuracy complex geometric features in a wide variety of materials in the above-defined size range. These requirements impose the use of considerably downsized tooling (micro-tools, e.g. endmills in the 50 to 500 micron diameter range), small undeformed chip thicknesses and feedrates (submicron to a few microns) and speed settings (50K to 200K RPM might not be uncommon) that would be considered technologically infeasible at the conventional macro-scale. As a consequence, the principal distinction between Macro and Micro-Machining operations emerges and manifests itself as the dominance of ploughing and rubbing phenomena at the cutting edge over shearing and the necessity to take micro-structural effects into consideration. (2) The second viewpoint approaches the definition of the Micro-Machining regime from the standpoint of the magnitude of the undeformed chip thickness being removed in the cutting process. It is difficult to define a clear-cut value of the undeformed chip thickness that would differentiate the macro-, micro/meso- and nano-scale cutting regimes since other factors such as grain-structure, cutting edge radius, etc., also come into play. The authors of this report would suggest the following classification: Miniaturization is the order of the day. Until recently a decade ago traditionally watch parts were considered to be the micro components one can think off. Recent changes in society’s demand have