Electrospun nanofibrous interleaves in composite laminate materials

Roberto Palazzetti

Research output: ThesisDoctoral Thesis

Abstract

The present work aims for investigate the influence of electrospun Nylon 6,6 nanofibrous mat on the behavior of composite laminates. The main idea is that nanofibrous interleaved into particular ply-to-ply interfaces of a laminate can lead to significant improvements of mechanical properties and delamination/damage resistance. Experimental campaigns were performed to investigate how nanofibers affect both the static and dynamic behavior of the laminate in which they are interleaved.
Mode I and Mode II fracture mechanics tests were initially performed on virgin and 8 different configuration of nanomodified specimens. The purposes of this first step of the work are (1) to understand which geometrical parameters of the nanointerleave influence the behavior of the laminate and, (2) to find the optimal architecture of the nanofibrous mat in order to obtain the best reinforcement. In particular, 3 morphological parameters are investigated: nanofibers diameter, nanofibers orientation and thickness of the reinforce. Two different values for each parameter have been used, and it leads to 8 different configurations of nanoreinforce. Acoustic Emission technique is also used to monitor the tests.
Once the optimum configuration has been found, attention is focused on the mechanism of reinforce played by the nanofibers during static and dynamic tests. Low velocity impacts and free decay tests are performed to attest the effect of nanointerlayers and the reinforce mechanism during the dynamic loads. Bump tests are performed before and after the impact on virgin and two different nanomodified laminates configurations. The authors focused their attention on: vibrational behavior, low velocity impact response and post impact vibration behavior of the nano-interleaved laminates with respect to the response of non-nanomodified ones.
Experiments attest that nanofibers significantly strength the delamination resistance of the laminates and increase some of their mechanical properties, such as energy absorbing capability, GIC, maximum stress before material crisis, absorbed energy during impact and residual strength. It is demonstrated that the nanofibers are capable to continue to carry on the loads even when the matrix around them is broken.
LanguageEnglish
QualificationPhD
Awarding Institution
  • University of Bologna
Supervisors/Advisors
  • Zucchelli, Andrea, Supervisor, External person
Award date21 Jun 2013
Publication statusPublished - 2014

Fingerprint

Laminates
Nanofibers
Composite materials
Delamination
Mechanical properties
Dynamic loads
Acoustic emissions
Fracture mechanics
Reinforcement
Experiments

Keywords

  • interlaminar stress
  • delamination resistance
  • electrospinning
  • polymeric nanofibers
  • composite material

Cite this

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title = "Electrospun nanofibrous interleaves in composite laminate materials",
abstract = "The present work aims for investigate the influence of electrospun Nylon 6,6 nanofibrous mat on the behavior of composite laminates. The main idea is that nanofibrous interleaved into particular ply-to-ply interfaces of a laminate can lead to significant improvements of mechanical properties and delamination/damage resistance. Experimental campaigns were performed to investigate how nanofibers affect both the static and dynamic behavior of the laminate in which they are interleaved.Mode I and Mode II fracture mechanics tests were initially performed on virgin and 8 different configuration of nanomodified specimens. The purposes of this first step of the work are (1) to understand which geometrical parameters of the nanointerleave influence the behavior of the laminate and, (2) to find the optimal architecture of the nanofibrous mat in order to obtain the best reinforcement. In particular, 3 morphological parameters are investigated: nanofibers diameter, nanofibers orientation and thickness of the reinforce. Two different values for each parameter have been used, and it leads to 8 different configurations of nanoreinforce. Acoustic Emission technique is also used to monitor the tests.Once the optimum configuration has been found, attention is focused on the mechanism of reinforce played by the nanofibers during static and dynamic tests. Low velocity impacts and free decay tests are performed to attest the effect of nanointerlayers and the reinforce mechanism during the dynamic loads. Bump tests are performed before and after the impact on virgin and two different nanomodified laminates configurations. The authors focused their attention on: vibrational behavior, low velocity impact response and post impact vibration behavior of the nano-interleaved laminates with respect to the response of non-nanomodified ones.Experiments attest that nanofibers significantly strength the delamination resistance of the laminates and increase some of their mechanical properties, such as energy absorbing capability, GIC, maximum stress before material crisis, absorbed energy during impact and residual strength. It is demonstrated that the nanofibers are capable to continue to carry on the loads even when the matrix around them is broken.",
keywords = "interlaminar stress, delamination resistance, electrospinning, polymeric nanofibers, composite material",
author = "Roberto Palazzetti",
year = "2014",
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Palazzetti, R 2014, 'Electrospun nanofibrous interleaves in composite laminate materials', PhD, University of Bologna.

Electrospun nanofibrous interleaves in composite laminate materials. / Palazzetti, Roberto.

2014.

Research output: ThesisDoctoral Thesis

TY - THES

T1 - Electrospun nanofibrous interleaves in composite laminate materials

AU - Palazzetti, Roberto

PY - 2014

Y1 - 2014

N2 - The present work aims for investigate the influence of electrospun Nylon 6,6 nanofibrous mat on the behavior of composite laminates. The main idea is that nanofibrous interleaved into particular ply-to-ply interfaces of a laminate can lead to significant improvements of mechanical properties and delamination/damage resistance. Experimental campaigns were performed to investigate how nanofibers affect both the static and dynamic behavior of the laminate in which they are interleaved.Mode I and Mode II fracture mechanics tests were initially performed on virgin and 8 different configuration of nanomodified specimens. The purposes of this first step of the work are (1) to understand which geometrical parameters of the nanointerleave influence the behavior of the laminate and, (2) to find the optimal architecture of the nanofibrous mat in order to obtain the best reinforcement. In particular, 3 morphological parameters are investigated: nanofibers diameter, nanofibers orientation and thickness of the reinforce. Two different values for each parameter have been used, and it leads to 8 different configurations of nanoreinforce. Acoustic Emission technique is also used to monitor the tests.Once the optimum configuration has been found, attention is focused on the mechanism of reinforce played by the nanofibers during static and dynamic tests. Low velocity impacts and free decay tests are performed to attest the effect of nanointerlayers and the reinforce mechanism during the dynamic loads. Bump tests are performed before and after the impact on virgin and two different nanomodified laminates configurations. The authors focused their attention on: vibrational behavior, low velocity impact response and post impact vibration behavior of the nano-interleaved laminates with respect to the response of non-nanomodified ones.Experiments attest that nanofibers significantly strength the delamination resistance of the laminates and increase some of their mechanical properties, such as energy absorbing capability, GIC, maximum stress before material crisis, absorbed energy during impact and residual strength. It is demonstrated that the nanofibers are capable to continue to carry on the loads even when the matrix around them is broken.

AB - The present work aims for investigate the influence of electrospun Nylon 6,6 nanofibrous mat on the behavior of composite laminates. The main idea is that nanofibrous interleaved into particular ply-to-ply interfaces of a laminate can lead to significant improvements of mechanical properties and delamination/damage resistance. Experimental campaigns were performed to investigate how nanofibers affect both the static and dynamic behavior of the laminate in which they are interleaved.Mode I and Mode II fracture mechanics tests were initially performed on virgin and 8 different configuration of nanomodified specimens. The purposes of this first step of the work are (1) to understand which geometrical parameters of the nanointerleave influence the behavior of the laminate and, (2) to find the optimal architecture of the nanofibrous mat in order to obtain the best reinforcement. In particular, 3 morphological parameters are investigated: nanofibers diameter, nanofibers orientation and thickness of the reinforce. Two different values for each parameter have been used, and it leads to 8 different configurations of nanoreinforce. Acoustic Emission technique is also used to monitor the tests.Once the optimum configuration has been found, attention is focused on the mechanism of reinforce played by the nanofibers during static and dynamic tests. Low velocity impacts and free decay tests are performed to attest the effect of nanointerlayers and the reinforce mechanism during the dynamic loads. Bump tests are performed before and after the impact on virgin and two different nanomodified laminates configurations. The authors focused their attention on: vibrational behavior, low velocity impact response and post impact vibration behavior of the nano-interleaved laminates with respect to the response of non-nanomodified ones.Experiments attest that nanofibers significantly strength the delamination resistance of the laminates and increase some of their mechanical properties, such as energy absorbing capability, GIC, maximum stress before material crisis, absorbed energy during impact and residual strength. It is demonstrated that the nanofibers are capable to continue to carry on the loads even when the matrix around them is broken.

KW - interlaminar stress

KW - delamination resistance

KW - electrospinning

KW - polymeric nanofibers

KW - composite material

M3 - Doctoral Thesis

ER -