An investigation on the feasibility of sputtering a diamond block into a specially designed three-dimensional cutting tool shape using a focused ion beam (FIB) was carried out. The ion-sputtered removal rate, surface morphology and sputtered feature accuracy were evaluated with respect to the FIB parameters such as ion current and angle of ion incidence through sputtering pockets on the top surface of a diamond substrate. A single crystalline diamond tool, with 25 µm length in the cutting edge and smooth face quality, has been successfully fabricated by using a FIB. These excellent tool characteristics are proven in the results obtained from the machining experiments done on the ultra-precision machine.

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A study was carried out to understand the physics of micro-scale mechanical machining (henceforth referred to as ‘micro-machining’) with a micro-size tool using a five-axis ultra-precision machine. A micro-size single crystalline diamond (SCD) tool with sharp cutting edges fabricated by a focused ion beam (FIB) was employed to orthogonal-machine four materials (three polycrystalline metals with various grain sizes and one amorphous metal plating material). Since the wealth of knowledge of macro-machining cannot be successfully used in micro-machining, this study contributes to the understanding of the physics of mechanical machining with micro-size tools.

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Chatter has been a problem in CNC machining process especially during pocket milling process using an end mill with low stiffness. Since an iterative time-domain chatter solution consumes a computing time along tool paths, a fast chatter prediction algorithm for pocket milling process is required by machine shop-floor for detecting chatter prior to real machining process. This paper proposes the systematic solution based on integration of a stability law in frequency domain with geometric information of material removal for a given set of tool paths. The change of immersion angle and spindle speed determines the variation of the stable cutting depth along cornering cut path. This proposed solution transforms the milling stability theory toward the practical methodology for the stability prediction over the NC pocket milling.