Experimental and computational study of the damage process in CFRP composite beams under low-velocity impact

Date

2017-01-01

Author

Topac, O. Tanay
Gözlüklü, Burak
Gürses, Ercan
Çöker, Demirkan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

239
views

0
downloads

Damage process in composites subjected to low-velocity impact is investigated both experimentally and numerically. Drop-weight impact experiments are carried out, in which a model unidirectional [0(5)/90(3)](s) CFRP laminate beam is impacted by a cylindrical head creating an almost uniform two-dimensional loading condition. Initiation and progression of damage, consisting of matrix cracks and delamination, are visualized in real-time via ultra-high-speed camera at rates up to 60,000 fps and the sequence of failure events are clearly captured. Evolution of dynamic strain fields in the laminate is then quantified by a Digital Image Correlation (DIC) analysis and the resulting final failure patterns are characterized by a digital microscope. In the computational part, a three-dimensional finite element analysis is performed using ABAQUS/Explicit to simulate the experiments. In these simulations, the intraply matrix damage in the middle 90 degrees layers is modeled using a Continuum Damage Mechanics (CDM) based composite failure theory with LaRC04 initiation criterion and implemented via a user-written VUMAT subroutine. Delamination is modeled using cohesive interface elements that are introduced between the 0 degrees/90 degrees interfaces. Damage initiation time, location and the interaction of failure modes are compared with the experimental data. Real-time observations of the sequentially occurring diagonal matrix cracking followed by dynamic delaminations are made. In addition to the major diagonal matrix cracks, existence of multiple diagonal micro-matrix cracks near the upper interface are shown which are also predicted by the simulations. Finally, experimentally obtained real-time strain field values, failure mechanisms and the failure sequence are shown to be in good agreement with the simulations. We believe that the elaborate experimental results presented here for an idealized composite layup can serve as a benchmark test case to validate composite and interface damage modeling methods.

Subject Keywords

Polymer-matrix composites (PMCs), Impact behavior, Finite element analysis (FEA), Failure

URI

https://hdl.handle.net/11511/44660

Journal

COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING

DOI

https://doi.org/10.1016/j.compositesa.2016.06.023

Collections

Department of Aerospace Engineering, Article

Suggestions

OpenMETU
Core

Experimental And Numerical Investigation Of Impact Induced Damage Progression in Fiber Reinforced Composites Gürses, Ercan; Çöker, Demirkan (null; 2016-08-21) Damage process in composites subjected to low-velocity impact is investigated both experimentally and numerically. Drop-weight impact experiments are carried out, in which a model unidirectional [0/90]s carbon fiber reinforced polymer (CFRP) laminate beam is impacted by a cylindrical head creating an almost uniform two-dimensional loading condition. Damage sequence is visualized in real-time via ultra-high-speed camera and the resulting final failure patterns are characterized by a digital microscope. I...
Simulation of Impact Induced Damage Process in a Carbon/Epoxy Composite Beam Bozkurt, Mirac Onur; Çöker, Demirkan; Parnas, Kemal Levend (2018-12-01) This paper presents numerical investigation of low-velocity impact (LVI) damage process in a unidirectional [0/90]s carbon/epoxy composite beam. Numerical simulations based on finite element method are conducted in ABAQUS/Explicit. A 3D model representing LVI experiments is generated. Matrix and fiber damage mechanisms are simulated by implementation of continuum damage mechanics based composite damage model with Hashin failure initiation criteria via a user-written VUMAT subroutine. Cohesive interfaces are...
Investigating the mechanical properties of single walled carbon nanotube reinforced epoxy composite through finite element modelling Zuberi, Muhammad Jibran Shahzad; Esat, Volkan (2015-03-15) Varying experimental results on the mechanical properties of carbon nanotube reinforced polymer composites (CNTRPs) have been reported due to the complexities associated with the characterization of material properties in nano-scale. Insight into the issues associated with CNTRPs may be brought through computational techniques time- and cost-effectively. In this study, finite element models are generated in which single walled carbon nanotube models are embedded into the epoxy resin. For modelling interface...
Investigation of tensile plastic instability and necking for AL2024T3 aluminum and S235JR steel alloys İli, Volkan; Darendeliler, Haluk; Department of Mechanical Engineering (2019) Tensile plastic instability phenomenon is defined as the mode of deformation so that large amounts of deformation is localized in a certain region of a component during product life or testing procedure. Several studies have been published to assess the methods proposed to predict tensile plastic instability and necking behavior of materials. Although research has been done by using various specimens, comparative results on different specimen materials and geometries as well as different test methods have n...
LINEAR CONTACT ALGORITHM FOR RIGID-PLASTIC FINITE-ELEMENT SIMULATION TEKKAYA, AE; SEN, A (1992-12-01) The rigid-plastic finite element analysis of metal forming processes is known to be much more efficient and stable than the elastic-plastic one. This efficiency results from the absence of kinematical nonlinearities in the formulation. Contact algorithms used in rigid-plastic models must agree with this fact, otherwise the efficiency can be damaged seriously.

Citation Formats

O. T. Topac, B. Gözlüklü, E. Gürses, and D. Çöker, “Experimental and computational study of the damage process in CFRP composite beams under low-velocity impact,” COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING, pp. 167–182, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/44660.