Processing, microstructure, and failure behavior in short‐fiber‐reinforced poly(ether ether ketone) composites

Abstract Short‐fiber‐reinforced poly(ether ether ketone) (PEEK) composites were prepared by a specially designed mold. Both compression‐ and extrusion‐molded plaques were obtained under the same thermal history. The fiber length distribution, fiber volume fraction, and fiber orientation are characterized. The fibers show an in‐plane random orientation in compression‐molded plaques, but they exhibit a 3‐layer fiber orientation well‐known for injection moldings in extrusion‐molded composites. It is the final aim to simulate the rheological and morphologic behavior in injection moldings by using the laboratory designed extrusion/compression mold. Static compact tension (CT) specimens and electron microscopy (EM) were used to investigate the failure behavior. Results showed that crack initiation is the dominant failure energy absorption process in a brittle fracture, whereas crack propagation is dominant in a ductile failure. The extruded composites were mechanically characterized in two orthogonal directions (T‐ and L‐type). The anisotropy factor is reported as 1.2.