Graphite Fiber Tensile Property Evaluation
SourceExisting techniques for the evaluation of single graphite fiber tensile properties are reviewed. Several problems associated with these techniques are identified and evaluated. Alternate procedures are demonstrated which significantly reduce the uncertainty introduced in denier measurement and operator selectivity.
In a separate approach to improved tensile property evaluation, dry bundle tension test procedures and analysis techniques are developed and demonstrated. With this approach average fiber tensile properties for the entire bundle can be generated by coupling the bundle breaking energy with the modulus determined by electrical resistivity. Moreover, analysis of the bundle stress-strain curve enables one to generate cumulative strength distribution data for the fibers involved. Both the average and cumulative data agree very well with results obtained via extensive single fil evaluation.