Accession Number:

ADA582343

Title:

Changes to Tensile Strength and Electromagnetic Shielding Effectiveness in Neutron Irradiated Carbon Nanocomposites

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT

Personal Author(s):

• Shinn, James F.

Report Date:

2013-03-01

Pagination or Media Count:

91.0

Abstract:

Electromagnetic interference shielding effectiveness EMI-SE and tensile strength of nanocomposites containing multi-walled carbon nanotubes MWNTs are investigated following neutron irradiation. This nanocomposite material consists of two plies of MWNTs in an epoxy resin, and 4 plies of an E-glass substrate. EMI-SE measurements over the X-band frequency spectrum and monotonic tension tests to determine Youngs Modulus were performed before and after irradiation on the nanocomposite material. The nanocomposite and the MWNT plies were irradiated to a total fluence of 1.4 x 1014 1 MeV Si-eq ncm2. The nanocomposites showed an average increase of 8 dB in shielding effectiveness after irradiation. However, the increase was not permanent with a return to pre-irradiation values after approximately 10 days at ambient temperature and pressure. The tensile strength and Youngs Modulus showed an 8 and 10 increase, respectively, following irradiation. This small increase is a result of the neutron induced embrittlement of the nanocomposite. Raman spectra of the MWNT plies showed a 150 increase in the DG peak ratios after irradiation. This indicates damage in the plies due to neutron interactions in the MWNTs that does not lead to a commensurate reduction in EMI-SE or tensile strength in the nanocomposite material.

Descriptors:

• *COMPOSITE MATERIALS
• CARBON NANOTUBES
• ELECTROMAGNETIC SHIELDING
• NEUTRON IRRADIATION
• RADIATION EFFECTS
• RAMAN SPECTROSCOPY
• TENSILE STRENGTH
• THESES

Subject Categories:

• Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE