Structure-properties relations in titanium-based thermoplastic fiber-metal laminates

This paper investigates the interfacial, tensile, and fatigue properties of a titanium alloy fiber-metal laminate (Ti-FML) based on woven glass-fiber-reinforced polyetherimide (GF/PEI). Initial tests, using the single cantilever beam (SCB) geometry have shown that it is not necessary to surface treat the titanium alloy in order to achieve a high value of metal-composite interfacial fracture toughness. Tensile tests have shown that the mechanical properties of the FML lie between those offered by its constituent materials. Tension-tension fatigue tests have shown that the fatigue lives of these laminates are superior to those offered by the plain titanium alloy. The mechanical properties of this glass fiber/PEI FML have also been compared with those offered by an FML based on a unidirectional carbon-fiber-reinforced polyetheretherketone (CF/PEEK) composite. Here, it has been shown that although the fatigue properties of this woven GF/PEI composite are inferior to those of the CF/PEEK FML, they do offer a higher temperature capability due to the higher glass transition temperature of the PEI matrix.