Laminated composites with nano fillers are subjected to medium velocity impact. The laminates are prepared by hand lay-up technique followed by compression moulding, for different thicknesses. Laminates are made of glass woven roving mates of 610 gsm, epoxy resin and nano clay. Clay dispersion is varied from 1% to 5% by weight. A piston type gas gun set up is employed to impact the composite laminates. Spherical nose cylindrical projectile, of diameter 9.5 mm and mass 7.6 g, is used for the study. The impact tests are conducted to predict the ballistic limits of the laminates with and without clay. Quasi-static deflection tests and dynamic tests are carried out to find the energy absorbed by the laminates. Dispersion of clay in polymer matrix shows considerable improvement in energy absorption and ballistic limit of the composite laminates. © 2013 Taylor and Francis Group, LLC.

R. Velmurugan

Department of Aerospace Engineering

G. Balaganesan

ABSORPTION CHARACTERISTICS

Ballistic limit

CLAY DISPERSION

composite laminate

DEFLECTION TEST

DYNAMIC TESTS

GAS GUN

Glass/epoxy

HAND LAY-UP

Impact

IMPACT LOADINGS

Impact test

NANO CLAYS

NANO-FILLERS

Quasi-static

SPHERICAL NOSE

VELOCITY IMPACT

WOVEN ROVING

Ballistics

Compression molding

Dispersions

Epoxy resins

Laminated composites

Laminates

Nanocomposites

Energy absorption

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Energy absorption characteristics of glass/epoxy nano composite laminates by impact loading

International Journal of Crashworthiness

This review paper initially summarizes the latest developments in impact testing on polymer matrix composites collating the various analytical, numerical, and experimental studies performed since the year 2000. Subsequently, the scientific literature investigating nanofiller reinforced polymer composite matrices as well as self-healing polymer matrix composites by incorporating core-shell nanofibers is reviewed in-depth to provide a perspective on some novel advances in nanotechnology that have led to composite developments. Through this review, researchers can gain a representative idea of the state of the art in nanotechnology for polymer matrix composite engineering, providing a platform for further study of this increasingly industrially significant material, and to address the challenges in developing the next generation of advanced, high-performance materials. © 2019 by the authors.

Fulltext

Polymers

A review of recent advances in nanoengineered polymer composites

In this study, the glass/epoxy composite laminate is layered with polyurethane foam/ polyurethane sheet and silicon carbide to analyse their response during high mass and low velocity impact. The silicon carbide is layered in two forms, one is as plate and the other is as inserts. The target materials are prepared in various combinations and the bonding of layers is done by using epoxy. Effectiveness of silicon carbide inserts and plates are compared in terms of their energy absorbing capacities. The numerical simulation is also carried for the target material with the same experimental conditions. The experimental results are compared with the numerical results for validation and a reasonably good agreement is found. Further, the validated numerical model is extended to understand the ballistic performance of the target material. It is observed that the introduction of silicon carbide as front layer improves both the structural and ballistic performance. Also, the damage in case of samples with silicon carbide inserts is localized as opposed to that of silicon carbide plate. © 2018, Brazilian Association of Computational Mechanics. All rights reserved.

Latin American Journal of Solids and Structures

Numerical study on multi layered target material subjected to impact loading

This study investigates energy absorption of thermally loaded composites and nanocomposites laminates during impact loading. The laminates are prepared by glass fiber/epoxy with and without nano particles in the matrix system. Nano clay and carbon nano tube are used as filliers in the epoxy matrix. The composites specimens are subjected to impact loading at 0° C, 30° C and 60° C temperature environments. A gas gun impact testing facility is used for propelling the projectile of mass 7.6 g and diameter 9.5 mm with hemi spherical nose. The initial and residual velocities of projectile are predicted to find the energy absorbing capacity of laminates. The energy absorption and delamination area of the specimens are analyzed and discussed for the laminates with and without clay. Also, the ballistic limit is predicted for the specimens of nanocomposites made with glass fibers and epoxy matrix, and the effect of temperature on impact resistance is discussed. Analytical model is developed and the energy absorption characteristics are also studied. © 2017 The Authors.

Procedia IUTAM

Impact Loading on Nanocomposites in Thermal Environment

This paper presents the analysis of repair of pipelines using nanofiller dispersed composites. Steel pipe with part wall loss as per ISO 24817 is repaired using glass/epoxy composites with and without nanoclay reinforcement and burst test is performed in order to assess the performance and effectiveness of nanocomposites-based repair system. A simple methodology is developed to find out the failure pressure of pipelines and is compared with the experimental and ISO 24817 repair code results. The thickness of the composite wrap is predicted analytically for 1-5% nanofiller dispersion in the epoxy for 30-80% of pipe wall loss and live pressure of pipe. The results are analyzed to find effectiveness of clay dispersion and effect of live pressure for 30-80% of pipe wall loss. It is observed that the dispersion of nanofiller improves the bursting resistance of composite wrapping over outer surface of pipe. © 2017 by ASME.

Journal of Pressure Vessel Technology, Transactions of the ASME

Nanofillers Reinforced Polymer Composites Wrap to Repair Corroded Steel Pipe Lines

Composite laminates are made of glass woven roving mats of 610gsm, epoxy resin and nano clay which are subjected to projectile impact. Nano clay dispersion is varied from 1% to 5%. Impact tests are conducted in a gas gun setup with a spherical nose cylindrical projectile of diameter 9.5 mm of mass 7.6 g. The energy absorbed by the laminates when subjected to impact loading is studied, the velocity range is below ballistic limit. The effect of nano clay on energy absorption in vibration, delamination and matrix crack is studied for different weight % of nano clay and for different thickness values of the laminates. The natural frequencies and damping factors are obtained for the laminates during impact and the effect of nano clay is studied. The results show considerable improvement in energy absorption due to the presence of nano clay. © 2015, Brazilian Association of Computational Mechanics. All rights reserved.

Vibration and energy dissipation of nanocomposite laminates for below ballistic impact loading

This paper deals with the effect of clay addition on improving the mechanical properties of epoxy polymer and glass fiber-reinforced epoxy-clay hybrid composites. The clays used in the present system were alkyl ammonium treated montmorillonite (MMT) based organoclay (OC) and unmodified MMT clay (UC). The OC and UC were added individually to epoxy polymer and glass fiber-reinforced epoxy composites. Structure and morphology of epoxy filled with OC and UC were examined by X-ray diffraction (XRD) and transmission electron microscope (TEM) techniques. It is observed that the clay nanolayer dispersion takes place in a polymer matrix filled with OC particles. However, the UC filled composites show the formation of micro-composites. The effects of clay addition (1ĝ€"3%, 5% and 10% by weight) in epoxy polymer shows that OC filled composites possess enhanced tensile strength over UC filled composites. A similar result is observed in the OC filled glass fiber-reinforced epoxy composites. Dynamic mechanical analysis (DMA) and thermogravimetry analysis (TGA) of hybrids show that the addition of OC increases the thermal properties of epoxy-glass fiber more than that of UC filled hybrids.

Journal of Reinforced Plastics and Composites

Epoxy-clay nanocomposites and hybrids: Synthesis and characterization

This study evaluates the energy absorption, perforation and damage evolution created by cylindrical projectile of different nose geometries in woven roving mat/epoxy laminates with 0.45° orientation. A series of ballistic impact tests have been carried out on the laminate with projectile nose geometries representing hemispherical, conical, and conical with round nose and truncated tip. A gas gun projectile launcher set-up was employed to impact the target at different speeds. The damage pattern, perforation mechanism and ballistic limit for each type of projectiles have been studied. Truncated-nose projectile shows the highest ballistic limit while sharp-nose shows the lowest. A quasi-static punch test was carried out on targets with projectiles of above-mentioned nose geometries to assess the damage evolution at a constant strain rate. The maximum load required to cause perforation during punch test was noted for hemispherical-nose projectile. An in-depth layerwise analysis was carried out to analyse the damage in each layer. Copyright © 2008 Taylor & Francis.

Energy-absorption capability of thin laminates subjected to heavy-mass projectile impact of varying nose geometries

This paper presents the experimental study of free vibration and damping characteristics of hybrid nanocomposite laminates by reinforcing short fibre chopped strand mat and organically modified montmorillonite clay (0, 1, 3 and 5 wt.%) in the vinyl ester matrix by hand lay-up technique. Theoretical study is also carried out to study the vibration and damping characteristics of hybrid nanocomposites. Dynamic result shows that the second phase nanoscale dispersion in the matrix and E-glass fibre significantly enhances the internal damping of hybrid composites. © 2007 Elsevier B.V. All rights reserved.

Materials Letters

Effect of nanoclay addition on vibration properties of glass fibre reinforced vinyl ester composites

Diglycidyl ether of bisphenol-A (DGEBA) epoxy resin system filled individually with organoclay (OC) and unmodified clay (UC) were synthesized by mechanical shear mixing with the addition of diamino-diphenylmethane (DDM) hardener. The unmodified clay used was Na+-Montmorillonite (MMT) and the organoclay was alkyl ammonium treated MMT clay. The reinforcement effect of OC and UC in the epoxy polymer on thermal, mechanical and vibration properties were studied. X-ray diffraction (XRD) and Transmission electron microscopy (TEM) were used to study the structure and morphology of nanocomposites. Curing study shows that the addition of OC in epoxy resin aids the polymerization by catalytic effect, and UC addition does not show any effect in the curing behavior of epoxy polymer. Thermogravimetry analysis (TGA) shows enhanced thermal stability for epoxy with OC fillers than that of epoxy with UC fillers. The epoxy with OC fillers shows considerable improvement on tensile and impact properties over pure epoxy polymer and epoxy with UC fillers. The improvement in tensile and impact properties of nanocomposites is supported with the fracture surface studies. Epoxy with OC fillers shows enhanced vibration characteristics than that of the pure epoxy polymer and epoxy with UC fillers.

Journal of Materials Science

Thermal, mechanical and vibration characteristics of epoxy-clay nanocomposites

Energy Dissipation in Composite Materials

Journal	International Journal of Crashworthiness
ISSN	13588265
Open Access	No