Session: 01-08-01: Nondestructive Evaluation and Structural Health Monitoring, 01-11-01: Wind Energy

Paper Number: 137779

137779 - Effect of Hybrid Lay-Up on Tensile Properties of Interlayer Hybrid Glass/carbon Non-Crimp Fabric Composites 

Non-crimp fabric (NCF) composites are a popular choice for applications in aerospace and wind energy, as they provide high in-plane strength and stiffness. This is due to the absence of crimping, which is commonly found in woven materials. However, as structures such as wind turbine blades become larger, it is harder to meet the necessary stiffness and weight requirements using only low-stiffness, high-density glass fibers. Carbon fibers offer a solution with high stiffness and low density, but they are very expensive compared to glass fibers, making them less attractive for low-cost industries such as wind turbine blades. Hybrid glass/carbon fiber epoxy laminates offer a promising solution, as they provide a compromise between cost and mechanical properties. These laminates have a synergistic effect due to the mutual contribution of the fibers to load distribution and interaction with resin. While most research on fiber hybridization has focused on woven composites, little is known about the effect of fiber hybridization, particularly ‘interlayer’ fiber hybridization, on the mechanical properties of NCF-based composites. ‘Interlayer’ fiber hybrid composites are created by stacking different layers of glass and carbon fibers in a specific orientation during the fiber deposition stage of the vacuum infusion process. 

The present study aims to (1) assess the effect of hybrid lay-up on the tensile properties of interlayer hybrid glass/carbon composites and compare the result to the non-hybrid glass and carbon composites, (2) examine the effect of hybrid lay-up on the damage initiation, evolution and failure of interlayer hybrid glass/carbon composites, and (3) explore the synergistic effects to correlate the obtained tensile properties and the underlying damage mechanisms. For this purpose, we use two non-hybrid composite laminates (glass and carbon) as the baseline and four hybrid variants with different placement of glass and carbon fiber layers. All six composite laminates are manufactured using the vacuum infusion process with NCF glass and carbon impregnated in an epoxy resin. The tensile test is conducted according to ASTM 3039. A high-speed camera is used to monitor the damage behavior from initiation to failure. Post-failure fractographic analysis is used to compare the fracture surface of the non-hybrid and hybrid composites to recognize possible synergistic effects. Finally, the results are summarized in a comparative table to provide an overview of the positive and negative synergistic effects compared to the non-hybrid glass and carbon composites. This study is the first attempt to understand the effect of hybrid lay-up on the tensile properties and identify the underlying synergistic effect of interlayer hybrid glass/carbon NCF composites. The findings contribute to lighter, cost-effective, and more reliable interlayer hybrid glass/carbon NCF composite structures. These composites benefit from synergistic effects to enhance their mechanical properties and damage resistance under tensile load.

Presenting Author: Amir Baharvand University of Maine

Presenting Author Biography: Amir is a Ph.D. student at the Department of Mechanical Engineering, University of Maine, US. He received his Bachelor's degree in Mechanical Engineering-Manufacturing from Azad University, Iran. Later, he obtained his Master's degree in Aerospace Engineering from Delft University of Technology, the Netherlands, and Wind Engineering from Technical University of Denmark, Denmark. His research includes damage tolerance of composite structures, fiber hybridization, and numerical modeling of composite structures.