Study of the Effect of Matrix, Fibre Treatment and Graphene on Delamination by Drilling Jute/Epoxy Nanohybrid Composite

Experimental Investigation of Thrust Force, Delamination and Surface Roughness in Drilling Hybrid Structural Composites

Filled hybrid composites are widely used in various structural applications where machining is critical. Hence, it is essential to understand the performance of the fibre composites’ machining behaviour. As such, a new hybrid structural composite was fabricated with redmud as filler and sisal fibre as reinforcement in polyester matrix. The composite was then tested for its drilling performance. A comprehensive drilling experiment was conducted using Taguchi L27 orthogonal array. The effect of the drill tool point angle, the cutting speed, the feed rate on thrust force, delamination, and burr formation were analysed for producing quality holes. The significance of each parameter was analysed, and the experimental outcomes revealed some important findings in the context of the drilling behaviour of sisal fibre/polyester composites with redmud as a filler. Spindle speed contributed 39% in affecting the thrust force, while the feed rate had the maximum influence of ca. 38% in affecting delamination.

Graphene-Incorporated Natural Fiber Polymer Composites: A First Overview

A novel class of graphene-based materials incorporated into natural lignocellulosic fiber (NLF) polymer composites is surging since 2011. The present overview is the first attempt to compile achievements regarding this novel class of composites both in terms of technical and scientific researches as well as development of innovative products. A brief description of the graphene nature and its recent isolation from graphite is initially presented together with the processing of its main derivatives. In particular, graphene-based materials, such as nanographene (NG), exfoliated graphene/graphite nanoplatelet (GNP), graphene oxide (GO) and reduced graphene oxide (rGO), as well as other carbon-based nanomaterials, such as carbon nanotube (CNT), are effectively being incorporated into NLF composites. Their disclosed superior mechanical, thermal, electrical, and ballistic properties are discussed in specific publications. Interfacial shear strength of 575 MPa and tensile strength of 379 MPa were attained in 1 wt % GO-jute fiber and 0.75 wt % jute fiber, respectively, epoxy composites. Moreover, a Young’s modulus of 44.4 GPa was reported for 0.75 wt % GO-jute fiber composite. An important point of interest concerning this incorporation is the fact that the amphiphilic character of graphene allows a better way to enhance the interfacial adhesion between hydrophilic NLF and hydrophobic polymer matrix. As indicated in this overview, two basic incorporation strategies have so far been adopted. In the first, NG, GNP, GO, rGO and CNT are used as hybrid filler together with NLF to reinforce polymer composites. The second one starts with GO or rGO as a coating to functionalize molecular bonding with NLF, which is then added into a polymeric matrix. Both strategies are contributing to develop innovative products for energy storage, drug release, biosensor, functional electronic clothes, medical implants, and armor for ballistic protection. As such, this first overview intends to provide a critical assessment of a surging class of composite materials and unveil successful development associated with graphene incorporated NLF polymer composites.

Investigation of Drilling Parameters Using Grey Relational Analysis and Response Surface Methodology of Biaxial Glass Fibre Reinforced with Modified Epoxy Resin Composite

This research work attempts to study the most prominent factor of the drilling operations performed on different thicknesses of biaxial glass fibre reinforced with graphene platelet nanopowder and epoxy composite using three different drills. Damages are induced in the workpieces to analyse the effect of changed cutting parameters and different tool materials for varied thicknesses of the plates during the drilling process. The resultant drilled hole exhibited surface irregularities that are measured using SURFCOM 1400G. The circularity deviations of the holes are measured using a coordinate measuring machine. Image-processing technique is used to calculate the area of maximum diameter of the damaged zone. Using these data, delamination at entry and exit is calculated. Utilizing response surface methodology and grey relational analysis, the varied operations are carried out and analysed with different tool materials for common cutting parameters. It is found that the lesser thickness workpiece with selected HSS drill under high speed and low feed rate is the best variable option.