Carbon fiber reinforced plastic (CFRP) composite materials are finding increased applications in many industries due to their excellent properties. Drilling of CFRP composites is needed for joining of these composite structures. During drilling, delamination is an important factor, which affects the property of the drilled hole. In this work experiments are conducted to analyze the delamination in drilling of CFRP composites. The cutting parameters considered are spindle speed, feed rate, and drill diameter. The tool material used for the present investigation is ‘‘BRAD and SPUR’’ type made of carbide. Second-order mathematical relation is established using response surface methodology for predicting delamination in drilling of CFRP composites. The results indicate that the model can be effectively used to predict the delamination in drilling of CFRP composites. The effect of different parameters in drilling of CFRP composites is analyzed and presented in detail.

Medium density fibre (MDF) panels find increased applications in wood industries. Drilling is frequently used machining process to join these materials. Surface quality and dimensional accuracy play an important role in the performance of joints. To make an effective use of MDF panels, it is essential to produce high quality holes. The objective of this study is to optimise the parameters such as thickness of panel, spindle speed, feed rate and drill size to get the optimum thrust force, so as to get good quality of holes during drilling MDF using design of experiments. The thrust force is measured by using drilling dynamometer. Response surface model is developed to predict the thrust force for drilling of MDF panels within the range of variables considered. From the response surface analysis, it is found that the drill sizes are very sensitive over the range of speed. Taguchi method and analysis of variance are employed to study the thrust force in drilling of MDF panels using (K20) carbide tools are presented in this study.

Recently, there has been rapid growth in research and innovation in natural fiber composites. The main reasons for the interest on these reinforcements over synthetic fiber reinforcements are their low environmental impact, low cost, and high flexural strength, which supports their potential across a wide range of applications. One of the promising applications of polymeric composite is polymeric gears, used in power and motion transmission work under different loads and speeds. In this work, polymeric spur gears are manufactured with various reinforcements like glass, sisal, and flax fiber in 15% and 20% weight percentage, and the gears are produced by molding process. The performance and wear of the gears are tested using a dynamic testing procedure. The tested gears are analyzed for modifications in tooth profile using scanning electron microscope. The weight loss as well as the thermal capability is studied using a contactless infra-red temperature (FLIR) camera. From the result, it is understood that the natural fiber-reinforced gears can be used for smooth and noiseless operation especially in intermittent applications.