Project Title:

Detection of Thermal Damage in Space Vehicles Using A Fourier-Transform-Raman Spectrometer

92-1-08.28-9806                                                     NASW-4796
Detection of Thermal Damage in Space Vehicles
     Using A Fourier-Transform-Raman Spectrometer
Advanced Fuel Research, Inc.
P.O. Box 380379
East Hartford, CT  06138-0379
Stuart Farquharson                                   (203-528-9806)

Abstract:

     A number of advanced, fiber-reinforced, organic-matrix
composites are being developed and applied in the aerospace
industry. In these applications, the composites may be exposed to
a variety of harsh environments that may induce chemical and
physical changes in the composite material and ultimately lead to
component failure. Therefore, the successful use of these
composites requires methods to reliably detect and assess these
changes. Although numerous techniques have been developed and
employed to analyze the chemical, physical, and mechanical
properties of composites as well as to define material flaws, none
of these techniques is amenable to at-site inspection of in-use
components with the capability of assessing the effect of damage
on future product performance. This project will develop and
employ a fiber-optic-based, Fourier-transform-Raman spectrometer
for the nondestructive evaluation of thermally damaged composite
materials. The system will correlate thermally induced changes in
Raman spectral features to changes in mechanical properties.
During Phase I, these measurements will be used to quantify the
degree of thermal damage. During Phase II, this information will
be used to develop a methodology to predict future component
performance. Also during Phase II, a prototype instrument with an
extended fiber optic probe will be developed with the potential of
accessing an entire space vehicle.

Potential Commercial Application:

Potential Commercial Applications:  The anticipated result of this
project is an instrument with a flexible sample probe capable of
assessing the effect of thermal damage on future performance of
composite materials. It could also be applied to the analysis and
assessment of a broad range of composite and substrate materials.
Because the instrument is designed to be rugged, portable, and
user friendly and can perform analysis in near real-time, it is
capable of use in process-control situations.

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