Titanium Ply Effects on the Behavior of a Hybrid Thermoplastic Composite Laminate

Abstract

An experimental-cum-analytical study was undertaken to investigate the mechanical response of four hybrid titanium composite laminate (HTCL) systems, each prepared using a graphite-fiber-reinforced thermoplastic polyimide as the adhesive in a unidirectional prepreg. Two of the four HTCL systems were fabricated with the titanium Ti15-3 alloy, while the other two systems were fabricated with the titanium Timetal fl-2 I S alloy. The improvement in mechanical properties achieved by the influence of the titanium layer was assessed by comparing the uniaxial tensile results of static strength at room temperature. An analytical study was also performed to predict the laminate strength and loaddeformation behavior based on the constituent material properties. Results included stressstrain curves, ultimate strength, longitudinal modulus, and the description of the observed modes of failure.

Keywords

hybrid composite high-temperature laminate thermoplastic polyimide analytical prediction titanium ply thermoelastic stresses tensile strength longitudinal modulus

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