Modal analysis is carried out on pre and post impacted nano composite laminates. The laminates are prepared using 3, 5 and 8 layers of 610gsm glass woven roving mats(WRM) with epoxy resin and montmorillonite(MMT) clay content is varied from 1% to 5%. Impulse hammer technique is used to find natural frequency and damping factor of laminates. Medium velocity impact tests are conducted by using a gas gun. The vibration responses of natural frequency and damping factor are obtained and are studied for laminates with all edges clamped boundary conditions. Results show considerable improvement in natural frequency and damping factor due to nano clay addition. It is also seen that the nano clay controls the delamination due to impact loading.

R. Velmurugan

Department of Aerospace Engineering

G. Balaganesan

Fulltext

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

Modal analysis of pre and post impacted nano composite laminates

Latin American Journal of Solids and Structures

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.

Polymers

A review of recent advances in nanoengineered polymer composites

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 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	Latin American Journal of Solids and Structures
Publisher	Brazilian Association of Computational Mechanics
ISSN	16797817
Open Access	No