Optimization of the effect of process parameters in drilling sisal-glass fiber reinforced hybrid nanocomposite

Abstract

Considering the current concern on environmental pollution and effective utilization of resources, hybrid natural fiber-reinforced nanocomposites are being immensely studied by material engineers. Available in nature, light in weight, superior properties are mainly accelerating its commercial application. Achieving the full potential of composite is not only dependent on the design and fabrication mechanism but also the secondary processing accuracy and among different secondary processing of polymer composite, drilling is the most performed machining process for mechanical fastenings. Surface quality, operational lifespan, structural integrity of machined parts has been greatly impacted by the proper selection of machine parameters as well as composition. Sisal-glass fiber reinforced hybrid composite with carbon nano tube (CNT) has been developed by hand layup method. Significant improvement in mechanical and physical properties has been observed with 2.0% weight ratio of CNT and 15% weight ratio of sisal and glass fiber with epoxy. The tensile strength, flexural strength and impact strength improved 26%, 133%, 100% and water absorption and swelling behavior reduced by 2.92% and 0.27% respectively. Drilling operation has been performed to measure the thrust force and taper angle. Response surface methodology (RSM) was employed to analyze the experimental data to identify the main and interaction effects of the chosen parameters and optimize the multi-response outcome. Again, the optimization of single response of thrust force and taper angle has been done by Taguchi analysis. It has been observed that feed rate and cutting speed are the most significant factors that affect thrust force and taper angle. The analysis using the desirability function revealed that the optimal parameters are 1.62% CNT, 6 mm tool diameter, feed rate of 0.05 mm/rev, and cutting speed of 1500 rpm, leading to a yield thrust force of 2N and a taper angle of 0.12°.Besides from the Taguchi analysis, single response optimization the optimal parameters are 1.0% CNT, 6 mm tool diameter, 0.05 mm/rev feed rate and 455 rpm cutting speed for the yielded thrust force of 2N and for the yielded taper angle of 0.2o, the parameters are 2.0% CNT, 10 mm tool diameter, 0.05 mm/rev feed rate and 1500 rpm cutting speed. Moreover, the quality of machine parts has distinctly affected by the structural integrity and the process parameters.