57th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference at AIAA SciTech 2016 San Diego, California, USA 4-8 January 2016

AIAA-2016-0937

Experimental Characterization and Computational Analysis of Mode I Fracture Toughness of a Nanocellulose Z-Pin Reinforced Carbon Fiber Laminate

K. Talamadupula, S. Berry, J. O'Donnell, G. Seidel, B. Goodell
Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061-0203, USA

This study investigates the functionality of Cellulose Nanofiber (CNF) in aiding the Mode I delamination resistance of carbon fiber composite laminates. Z-Pinning as well as Wet Flocking techniques are utilized to study the through thickness reinforcement. Experimental Analysis is done on unreinforced and reinforced (Z-Pin, Wet Flocking etc.) Double Cantilevered Beam (DCB) specimens in accordance with the standard ASTM D5528 – 13. Numerical simulations will be conducted using a 2D finite element code with plane strain finite elements. A traction-separation based bilinear cohesive model will be utilized in studying the effect of through thickness reinforcement. The parameters for the cohesive zones are obtained through a parametric study and the results are then corroborated with obtained experimental data. The initiation and propagation of delamination in the model will be captured effectively with the help of Force vs Crosshead Deflection plots. The use of a bilinear cohesive law dictating the z-pin pullout behavior will also be validated.