Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.

Bibliographic Details
Main Author: Saini, Gagan
Other Authors: Keith A. Nelson.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2007
Subjects:
Online Access:http://hdl.handle.net/1721.1/37681
_version_ 1826213529626083328
author Saini, Gagan
author2 Keith A. Nelson.
author_facet Keith A. Nelson.
Saini, Gagan
author_sort Saini, Gagan
collection MIT
description Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.
first_indexed 2024-09-23T15:50:41Z
format Thesis
id mit-1721.1/37681
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T15:50:41Z
publishDate 2007
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/376812019-04-11T06:06:31Z Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials Saini, Gagan Keith A. Nelson. Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. Materials Science and Engineering. Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006. Includes bibliographical references (p. 85-95). A detailed understanding of how materials respond to ballistic shock-loading is critical for the design and development of new protective materials. However, the nonlinear viscoelastic deformation present in polymers and nanocomposites during and immediately following a ballistic impact event is not currently well understood. The dynamic mechanical responses of materials experiencing ballistic shock-loading conditions are quite complex, with large amplitude compressions resulting in strain rates in excess of 106 s-1 and pressures exceeding several GPa. Historically, if one wants to study materials under ballistic shock loading conditions, a gas gun apparatus is necessary to generate appropriate high strain rate events. However, advances in high power ultra-fast laser amplifier systems have opened the possibility of optically generating ballistic shocks which are comparable to a shock wave generated by gas gun apparatus. Time-resolved mechanical property information, such as elastic modulus, bulk modulus, shear modulus, and Poisson's ratio are measured using impulsive stimulated thermal scattering, a laser-based photoacoustic technique. (cont.) A series of polymeric and polymer based nanocomposite material systems are studied, including multilayered thin films of alternating layers of polymer and hard nanoparticles, un-annealed and fully annealed poly(methyl methacrylate) (PMMA)-polyisoprene block copolymer thin films, and polyhedral oligomeric silsesquioxane (POSS) doped PMMA thin films. The experimental results on these materials clearly demonstrate that this technique is sensitive enough to measure mechanical property differences in samples with only small compositional or structural changes. Since the data can be acquired in real time, or a single shot basis, the measurement is compatible with laser shock loading of the sample. This is demonstrated by preliminary experimental results. by Gagan Saini. M.Eng. 2007-06-28T12:22:31Z 2007-06-28T12:22:31Z 2006 2006 Thesis http://hdl.handle.net/1721.1/37681 126888698 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 95 p. application/pdf Massachusetts Institute of Technology
spellingShingle Materials Science and Engineering.
Saini, Gagan
Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title_full Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title_fullStr Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title_full_unstemmed Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title_short Time-resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
title_sort time resolved spectroscopic characterization of ballistic impact events in polymer and nanocomposite materials
topic Materials Science and Engineering.
url http://hdl.handle.net/1721.1/37681
work_keys_str_mv AT sainigagan timeresolvedspectroscopiccharacterizationofballisticimpacteventsinpolymerandnanocompositematerials