Predictive model for surface accuracy in ultra-high precision single point diamond machining of monocrystalline silicon using RSM and MD

Silicon has enjoyed extensive usage in electronic devices, solar cells and infrared (IR) optics because of its high transmittance at 1.2 to 6.0 μm wavelength range. High quality optical silicon components (Ra less than 8 nm) requires appropriate choice of ductile regime machining cutting conditions that can improve surface roughness and facilitate accurate prediction. To achieve this, three factors, i.e., feed rate, rake angle and nose radius were varied while keeping cutting speed, depth of cut and clearance angle constant. An MD study of the experiment was also carried out for comparison. The result obtained showed that; BBD standard runs 5, 6, 8, 9, and 10 with Ra values between 1.8 and 7 nm are of high form accuracy and satisfied the basic requirement of Ra over the entire IR region for silicon. The MD study was also observed to conform with the Ra result as obtained in the experiment.