Electrical resistance measurements of highly inhibited SiC coated carbon-carbon laminates

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references: p.57-58.Issued also on microfiche from Lange Micrographics.The effect of oxidation damage at 900'C of highly inhibited, SiC coated carbon-carbon laminates on shear modulus, mass loss, and electrical resistance are studied. The approach taken enabled the interpretation of the shear modulus and electrical resistance values to the mass loss. In-situ electrical resistance measurements are taken at 900'C and shear modulus measurements are obtained at room temperature prior to and following oxidation. Initial oxidation damage is incurred preferentially along both transverse and longitudinal fiber bundles as well as creating some matrix cracks. Mass loss results revealed that the oxidation reaction is diffusion controlled at this temperature. The shear modulus decreased whereas the electrical resistance increased with increasing exposure time. Electrical resistance calculations based on the experimental results showed that the electrical resistance is a matrix dominated property. The analytical simulations used in conjunction with experimental data provided the relationships between shear modulus, electrical resistance, and mass loss. Examples are given which show the correlation of mass loss to both the electrical resistance and the shear modulus. Analytical predictions from the electrical resistance simulations are shown to predict the shear modulus for different oxidation times within 5% of experimental values