ENERGY-ABSORPTION BEHAVIOR OF CARBON-FIBER-REINFORCED THERMOPLASTIC COMPOSITE TUBES

The primary objective of this work was to study the energy absorption characteristics of carbon-fiber-reinforced thermoplastic composite tub es. Composite tubes with different thermoplastic matrices-polyethereth erketone (PEEK), polyetherimide (PEI), polyimide (PI), and polyarylsul fone (PAS)-have been investigated. Fiber orientations of 0-degrees, +/ - 5-degrees, +/- 10-degrees, +/- 15-degrees, +/- 20-degrees, +/- 25-de grees and +/- 30-degrees with respect to the axis of the tube were use d. Among the thermoplastic tubes investigated, the carbon fiber/PEEK t ubes displayed the highest specific energy absorption capability. This was attributed to the superior fracture toughness of the carbon fiber /PEEK composite material and a large number of frond splits and fractu red fibers in the crush zone. The specific energy absorption capabilit y was dependent on the fiber orientation. Efforts have been made to re late the change in specific energy to the variation of microfracture p rocesses in the crush zone.