Accurate mechanical properties are critical to the design and use of composite
material structures. Due to the available processing methods, the properties of
ceramic matrix materials are especially sensitive to the geometry of the component
and how it is made. A method is presented by which the ply-level elastic properties
of a composite material can be obtained for a common structure; a thick, laminated
tube. The mechanical and thermal response of the tubes is modeled by a planar
cylindrical elasticity solution. Properties are determined from surface strain
measurements of a thick tube subject to axial, torsional, pressure, and thermal
loads. All elastic properties (including thermal expansion coefficients) can be
obtained except the out-of-plane shear moduli (G13, G23) which are not involved in
the planar elasticity solution employed. The ply-level properties are estimated by
inversion of the elasticity solution in terms of the global strain measurements. A
Least Squares optimization approach is used for the inversion of the elasticity
solution. Application of the method for a filament wound aluminum oxide-aluminum
oxide tube is presented. Advantages and limitations of the method are identified.
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