Mechanical characterization of hierarchical carbon fiber/nanofiber composite laminates

作者：Bortz Daniel R^*; Merino Cesar; Martin Gullon Ignacio

来源：Composites Part A: Applied Science and Manufacturing , 2011, 42(11): 1584-1591.

DOI：10.1016/j.compositesa.2011.07.002

• Polymer-matrix composites
• Carbon fiber
• Mechanical properties
• Strength

Susceptibility to matrix driven failure is one of the major weaknesses of continuous-fiber composites. In this study, helical-ribbon carbon nanofibers (CNF) were dispersed in the matrix phase of a continuous carbon fiber-reinforced composite. Along with an unreinforced control, the resulting hierarchical composites were tested to failure in several modes of quasi-static testing designed to assess matrix-dominated mechanical properties and fracture characteristics. Results indicated CNF addition offered simultaneous increases in tensile stiffness, strength and toughness while also enhancing both compressive and flexural strengths. Short-beam strength testing resulted in no apparent improvement while the fracture energy required for the onset of model interlaminar delamination was enhanced by 35%. Extrinsic toughening mechanisms, e.g., intralaminar fiber bridging and trans-ply cracking, significantly affected steady-state crack propagation values. Scanning electron microscopy of delaminated fracture surfaces revealed improved primary fiber-matrix adhesion and indications of CNF-induced matrix toughening.

• 出版日期2011-11