On the Interpretation of Off-Axis Thermal Diffusivity Data for Coarse-Weave Composites
An off-axis test for the determination of thermal diffusivity along the principal axes of coarse-weave composites was suggested recently due to its potential in reducing percentage rise-fraction effects. In the present paper an evaluation of off-axis testing is presented based on the available data suggesting that more careful study is needed to conclude that off-axis testing is a more reliable means of obtaining on-axis thermal diffusivity values. It is also suggested that the off-axis sample cut at 45° direction may not always result in the 45° off-axis thermal diffusivity values.
KeywordsThermal Diffusivity Fiber Fraction Unique Direction Sample Axis Measured Thermal Diffusivity
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