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Polymer chemists developed advanced thermoplastic matrices suitable for high-performance composites. The result is a new class of composites with short processing times, damage tolerance superior to that of traditional thermosetting polymer matrix composites and an adequate solvent resistance. Emphasis is placed on the role of the matrix on thermo mechanical behavior in various composite microstructures. Especially surface quality and dimensional accuracy play an important role in the performance of a machined components of thermoplastic composites. In machining processes, however, the quality of the component are greatly influenced by the cutting conditions, tool geometry, tool material, machining process, chip formation, work piece material, tool wear and vibration during cutting. To make an effective use of composites, it is essential that a high degree of confidence be achieved in predicting the process state variables. The objective is to optimize the parameters such as specimen thickness, cutting speed, feed and drill size to get the best surface roughness of the drilled surface using response surface analysis. The developed models can be used to predict the surface roughness for drilling of GFRP composites with in the range of variables studied. A series of experiments are conducted using TRIAC VMC CNC machining center for drilling GFRP specimens with various machining conditions. The surface roughness of the drilled holes was measured using Rank Taylor Hobson Surtronic 3+. The measured results were collected and analyzed with the help of the commercial software package MINITAB14 and Taly Profile. The method could be very useful in optimizing the surface roughness and quantifies the relationship between the controllable input parameters and the obtained response surfaces. From the response surface analysis it is found that the surface roughness improves with decrease in spindle speed and increase feed rate on a given specimen and drill bit during drilling force. From the over laid plot of surface roughness with feed and speed for the optimum condition, it can be observed that the high surface roughness is spread in whole range of feed rates and high speed conditions.
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