Role of Laminate Thickness on Sequential Dynamic Delamination of Curved [90/0] CFRP Composite Laminates


Uyar I., Tasdemir B., Yavas D., ÇÖKER D.

SEM Annual Conference and Exposition on Experimental and Applied Mechanics, Florida, United States Of America, 6 - 09 June 2016, pp.43-48 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1007/978-3-319-42195-7_7
  • City: Florida
  • Country: United States Of America
  • Page Numbers: pp.43-48
  • Keywords: Delamination, L-shaped laminates, Dynamic crack growth, High-speed camera
  • Middle East Technical University Affiliated: Yes

Abstract

In aerospace industry, high demand for the lightweight structures are fostering the use of carbon fiber reinforced polymer composites in a wide variety of shapes, as primary load carrying elements. However, once a composite laminate takes a highly curved shape, such as an L-shape, interlaminar stresses augmented in the curved region cause highly dynamic delamination nucleation and propagation. This paper provides experimental observations of dynamic delamination failure in cross-plied L-shaped composite laminates under quasi-static shear loading for varying laminate thickness. In the experiments, load-displacement curves are recorded and dynamic delamination events areas captured using a million fps high speed camera. In our previous work, two distinct types of failure modes have been identified depending on the laminate layup: (i) formation of multiple delaminations leading two single load drop in its load-displacement curve during the failure of unidirectional laminates, [0](17), and (ii) formation of sequential delaminations associated with each discrete load drop in its load-displacement curve were during the failure of cross-ply laminates, [90/0](17). Accordingly this current study shows that formation of sequential delaminations is independent from the laminate thickness.