The manufacturing of parts from nickel-based superalloy, such as Inconel-800 alloy, represents a challenging task for industrial sites. Their performances can be enhanced by using a smart cutting fluid approach considered a sustainable alternative. Further, to innovate the cooling strategy, the researchers proposed an improved strategy based on the minimum quantity lubrication (MQL). It has an advantage over flood cooling because it allows better control of its parameters (i.e., compressed air, cutting fluid). In this study, the machinability of superalloy Inconel-800 has been investigated by performing different turning tests under MQL conditions, where no previous data are available. To reduce the numerous numbers of tests, a target objective was applied. This was used in combination with the response surface methodology (RSM) while assuming the cutting force input (F c), potential of tool wear (VB max), surface roughness (Ra), and the length of tool-chip contact (L) as responses. Thereafter, the analysis of variance (ANOVA) strategy was embedded to detect the significance of the proposed model and to understand the influence of each process parameter. To optimize other input parameters (i.e., cutting speed of machining, feed rate, and the side cutting edge angle (cutting tool angle)), two advanced optimization algorithms were introduced (i.e., particle swarm optimization (PSO) along with the teaching learning-based optimization (TLBO) approach). Both algorithms proved to be highly effective for predicting the machining responses, with the PSO being concluded as the best amongst the two. Also, a comparison amongst the cooling methods was made, and MQL was found to be a better cooling technique when compared to the dry and the flood cooling.

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Fiber-reinforced plastic is one of the top priorities lightweight materials with excellent mechanical properties for the aerospace industries in recent years. However, it is difficult to machine despite having unique properties due to its non-homogeneous and abrasive nature in alternate fiber and matrix layers. Thus, it is found to be a challenging task to drill hole on such hard-to-machine materials, which is highly essential for the development of most of the engineering structural components. The present work addresses various drilling-induced defects such as delamination, circularity error, and roughness variations in the hole surface during drilling of quasi-isotropic cross-fiber oriented bi-directional woven-type carbon fiber reinforced plastic laminate using a full factorial design of experiments for different drill geometry. The response surface methodology was considered for the regression model development, which was found to be highly significant. The machining forces with associated torque have also been acquired during drilling, which was divided and further analyzed in time domain to correlate with drilling flaws. The drilling-induced delamination was found to be higher at a high feed rate using a higher drill point angle due to substantial thrust force generation at the initial stages in the drilling cycle. However, the internal surface finish with associated circularity error was reduced for higher spindle speed with less feed rate using a low drill point angle because of low torque fluctuation at the final drilling phases. The axial thrust force was found to be a prime indicator of drilled hole surface delamination, whereas drilling torque precisely indicated internal surface roughness as well as circularity error. The global root mean square, along with a local peak of thrust and torque, both were highly essential to completely characterize the drilled hole quality.

Recently, dielectric elastomers (DEs) become enviable materials for the applications of electromechanical transducers. However, requirements of enhanced properties like high dielectric constants, low elastic moduli, high stretchability, and minimum viscous and dielectric losses are major challenges for actuator and generator applications. To enhance dielectric properties, particle‐filled DE can be prepared in the presence of an electric field during the curing process, which leads to aligned particles in a regular fashion. In this work, we develop a holistic experimental characterization approach to assess how particle alignments enhance mechanical, electrical and electro‐mechanical properties over the randomly particle filled composites. For that, a commercially available silicone polymer (Ecoflex) is used and filled with high dielectric constant barium titanate fillers. In order to substantiate electromechanical performance enhancements, mechanical, electrical, electro‐mechanical, and morphology experiments are conducted on both types of silicone composites. Dielectric composites prepared under an electric field during curing process outperform in almost all aspects of electromechanical tests. This comprehensive study provides a framework that will guide future dielectric composite preparations and electrical, mechanical, and electromechanical experiments especially for the oriented dipole fillers prepared under an electric field.

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