In the present study, the synergistic effect of hybrid boron nitride (BN) with graphene on the thermal conductivity of epoxy adhesives has been reported. Graphene was prepared by chemical reduction of graphite oxide (GO) in a mixture of concentrated H2SO4/H3PO4 acid. The particle size distribution of GO was found to be ~10 μm and a low contact angle of 54° with water indicated a hydrophilic surface. The structure of prepared graphene was characterized by Fourier transform infrared (FTIR), X‐ray diffraction (XRD), Raman spectroscopy and atomic force microscopy (AFM). The thermal conductivity of adhesives was measured using guarded hot plate technique. Test results indicated an improvement in the thermal conductivity up to 1.65 W/mK, which was about ninefold increase over pristine epoxy. Mechanical properties of different epoxy formulations were also measured employing lap shear test. The surface characterization of different epoxy adhesive systems was characterized through XRD, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies. Fourier transform infrared also served to determine the nature of interactions between filler particles and epoxy resin. Non‐isothermal differential scanning calorimetric (DSC) technique was used to investigate the effects of graphene and BN particles on the cure kinetics and cross‐linking reaction of epoxy cured with amine curing agent. The Kissinger equation, the model‐free isoconversional Flynn–Wall–Ozawa method and the Ozawa model were used to analyze the kinetic parameter. Copyright © 2017 John Wiley & Sons, Ltd.

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High aspect ratio micro tools find numerous applications in the production of miniaturized components and structures for example, drilling of micro holes in ink jet nozzles, air bearings and biomedical devices, etc. The present study aims to machine micro rods using Reverse Micro Electrical Discharge Machining (R-µEDM) process.These micro rods can be used as micro tools for drilling micro holes. A detailed experimental investigation has been carried out with the help of Taguchi's orthogonal array for understanding the mechanism of the process. The process parameters such as voltage, feed rate and capacitance are considered to perceive their effect on response measures such as machining time, deviation in length, deviation in average diameter, standard deviation (SD) in diameter and surface roughness. The optimal process parametric condition of R-µEDM has been determined for desired performance i.e., obtaining the target length and average diameter of the micro rod and ensuring its straightness with minimum time duration. Confirmation experiment has been carried out at the optimum condition and accordingly the results have been presented. Surface morphology of the machined micro rod at the optimum condition has also been Downloaded by [University of Otago] at 21:36 27 July 2015 2 investigated. Micro rod of diameter 170 µm with a high aspect ratio of 18 has been successfully machined using this process.