Burrs control and prevention in micromilling processes are essential for micromilling of miniature and micro components or products. The tool cutting edge radius plays an important role in burr formation and predominately governs the burr size in specific material micromilling. The cutting edge radius determines the effective rake angle and pressure status around the engaged cutting zone. The larger the edge radius is, the more remarkable of ploughing or extrusion effect is and thus burr formation and negative shear zone. Furthermore, burr formation mechanism is presented from the view of 'boundary effect' at entry and exit edges of workpiece, which results in deformation instability. Finally, two micromilling strategies are proposed for preventing or control of burrs generation. One is to decrease the cutting edge radius, and the other is to deposit low-melting point alloy on the component to be machine, which is verified with a case study.
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