Viscoelastic Behavior of a Polyetheretherketone (PEEK) Composite.
Abstract
The thermoplastic polyetheretherketone (PEEK) is being considered for structural applications in the Advanced Tactical Fighter. Previous efforts characterizing PEEK mechanical properties are reviewed. A study developing the viscoelastic frequency-temperature response to three point flexure of neat resin and PEEK/graphite fiber composites is detailed. The behavior of unidirectional laminates is compared to predictions from elastic plate theory, which also combines micro- and macromechanical approaches to predict transverse and longitudinal complex moduli. The experimental frequency-temperature shift factors, obtained under low strain in a Dynastat dynamic viscoelastic analyzer, are compared to shift factors predicted from the Williams-Landel-Ferry equation. Determining composite behavior from knowledge of matrix and fiber behavior is still applicable. The capability of the Dynastat to perform viscoelastic characterizations of stiff, unidirectional composites, based on comparisons of the various shift factors, is reduced due to the presence of the reinforcing fibers. Recommendations for future test and evaluations, including increasing the dynamic signal-to-noise ratio, are described.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA189545
Entities
People
- Richard P. Lockwood
Organizations
- Air Force Institute of Technology