Session: 17-01-01: Research Posters

Paper Number: 149499

149499 - Performance Evaluation and Modeling of Hybrid Composite Laminates Under Low-Velocity Impact Loading: Enhancing Impact Resistance 

In the contemporary aerospace industry, composite materials constitute a significant portion 50% or more of structural components in air vehicles. However, these advanced materials, unlike traditional metal alloys, exhibit suboptimal resistance to out-of-plane impact events such as bird strikes, lightning, and hail. Traditionally aramid fiber-reinforced composites stand out for their exceptional impact resistance properties, often utilized in applications ranging from personnel body armor to armored vehicle shells for ballistic protection.

This study aims to assess the impact damage tolerance of hybrid composite laminates by integrating aramid fabric into carbon/s-glass structures. Three distinct configurations: pure carbon, carbon/s-glass hybrid, and carbon/aramid/s-glass hybrid laminates were fabricated using the prepregs and were cured using autoclave method. All the test coupons were stacked up with quasi-isotropic layup. Total of 20 layers of carbon plain weave composite prepregs were used.  In the case of carbon/fiberglass configuration, 16 layers of plain weave prepregs were sandwiched between four layers of s-glass plain weave prepregs. Finally in the case of carbon, fiberglass, and aramid hybrid laminates, 2 s-glass plain weave laminated followed by 2 aramid laminates, followed by 4 carbon plain weave laminated were stacked with mid- plane symmetry resulting inro 20 layers of hybrid composite laminates. All the laminates were fabricated using autoclave methods under same pressure and temperature for curing of the laminates.  In addition, separate panels for each of the material, carbon, s-glass and aramid were fabricated to obtain the basic fundamental properties that are needed for the finite element modeling. These fundamental properties includes various moduli and strengths including tensile, compression, and shear, strengths were determined using conventional ASTM standards,

Low velocity impact tests were performed according to ASTM D7136 standards. The laminates were subjected to incremental impact energies to analyze energy absorption and damage evolution up to maximum sustainable thresholds. Post-impact, residual strength was evaluated per ASTM D7137 guidelines. The findings unequivocally demonstrate that hybridizing carbon composites improves out-of-plane impact resistance, particularly crucial in structural design considerations.

Subsequently, leveraging experimental data alongside ANSYS finite element analysis (FEA) software, the hybrid composite configurations were simulated to further elucidate their performance characteristics. FEA results were validated against experimental data, affirming their accuracy. Moreover, various laminate stacking sequences were explored in the models to optimize impact damage tolerance through different hybridization strategies.

This comprehensive approach sheds light on the efficacy of hybrid composite designs in enhancing structural resilience against out-of-plane impacts, offering insights into potential applications across diverse aerospace and industrial sectors.

 

Presenting Author: Ajit Kelkar North Carolina A&T State University

Presenting Author Biography: Dr. Ajit D. Kelkar is a Professor of Mechanical Engineering at North Carolina A&T State University in Greensboro, NC, USA. He is a founding Chair of Nanoengineering Department at Joint School of Nanoscience and Nanoengineering. He is also a Founding Chair of Computational Science and Engineering Department and founding Director of Center for Advanced Manufacturing at A&T. For the past 25 years he has been working in the area of applications of Nanoscience and Nanoengineering in various fields, including Nano electronics, Nanomaterials for aerospace and automotive applications, Nano devices, Nano-bio etc. In addition, he also has been working in the area of performance evaluation and modeling of polymeric composites and ceramic matrix composites. He has worked with several federal laboratories in the area of fatigue, impact and finite element modeling of woven composites including US Army, US Air force, NASA-Langley Research Center, NASA Kennedy Space Center, National science Foundation, Office of Naval Research, FAA and Oak Ridge National Laboratory. His expertise are in the area of nanoengineered materials, low cost fabrication and processing of woven composites using VARTM process, fatigue and impact testing of composites, analytical modeling of woven composites. Presently he is involved in the development of nano engineered multifunctional materials using CNTs, BNNTs and electro spun fiber materials, nanoengineered radiation shielding materials. He has published over three hundred papers in these areas. He has edited two books in the area of Nanoscience and Nanoengineering and has three patents and 16 invention disclosures in the area of composite manufacturing. He has received numerous awards including Senior Researcher Award, Intellectual Property Award at North Carolina A&T State University. He is Fellow of Maharashtra Academy of Science, India. He serves on editorial board for three journals in nanotechnology areas. He is member of several professional societies including ASME, SAMPE, AIAA, ASM, MRS, and ASEE. He has supervised over 50 MS/PhD students and several post-doctoral fellows.

Authors:

Joshua Tucker North Carolina A&T State University
Ajit Kelkar North Carolina A&T State University