Machining of polycarbonate for optical applications

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2013
Bolat, Müslüm
Polycarbonate is a very strong and durable material, highly transparent to visible light, with superior light transmission compared to many kinds of glass. Due to its superior properties, polycarbonate is one of the most common materials used in optical applications. Since surface quality is the main issue for optical performance, optimum cutting conditions should be examined to achieve the best surface quality. In this thesis, the effects of cutting parameters and vibration on product quality are experimentally studied. Polycarbonate specimens are machined by Single Point Diamond Turning machine and the roughness values of the diamond turned surfaces are measured by White Light Interferometer. A Bruel & Kjaer 4524B accelerometer is used to gather vibration data. Optimum cutting conditions are investigated by three-level full factorial design and an empirical formula is obtained to determine the surface roughness by considering feed rate, depth of cut and spindle speed. Artificial Neural Network (ANN) modeling is also implemented to predict the surface roughness for different cutting conditions. During experiments, the best average surface roughness value is achieved as 2.7 nm which greatly satisfies the demand for optical quality.

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Citation Formats
M. Bolat, “Machining of polycarbonate for optical applications,” M.S. - Master of Science, Middle East Technical University, 2013.