Article
Materials Science, Multidisciplinary
Min Li, Zhe Che, Shaokai Wang, Yubo Zhou, Hao Fu, Yizhuo Gu, Wei Zhang
Summary: By implanting fine z-pins on the in-plane fibers, the interlaminar fracture toughness of carbon fiber reinforced polymer (CFRP) composites can be significantly improved, while maintaining high retentions of in-plane mechanical properties. The mechanical properties of the carbon fiber pins play a crucial role in enhancing the composite laminate.
MATERIALS & DESIGN
(2021)
Article
Engineering, Mechanical
Sahand P. Shamchi, Marcelo F. S. F. de Moura, Zhongjie Zhao, Xiaosu Yi, Pedro M. G. P. Moreira
Summary: The study found that the critical strain energy release rate of the modified laminates increased by nearly 79% compared to the reference samples under quasi-static loading conditions. In terms of the influence of loading rate on mode II interlaminar fracture toughness values, non-modified carbon/epoxy laminates showed a marginal increase, while the interleaved ones showed no significant effect.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2022)
Article
Materials Science, Composites
Yusuf Polat, Bulent Ekici, Ali Kilic
Summary: The study showed that solution-blown nanofiber coatings improved the Mode-I fracture toughness of carbon fiber-reinforced epoxy composites by stabilizing crack propagation and increasing delamination strength. Dynamic mechanical analysis demonstrated that nanofibers increased material stiffness even with a small coating amount.
POLYMER COMPOSITES
(2021)
Article
Engineering, Multidisciplinary
Philipp Hahn, Harichandana Channammagari, Mathieu Imbert, Michael May
Summary: This paper presents a novel high-rate transverse crack tension (TCT) test for determining mode II fracture toughness under high strain rates. The results show that the fracture toughness of the tested composite under high-rate loading is at least 50% higher compared to quasi-static loading.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Materials Science, Composites
Zhe Che, Min Li, Shuo Wang, Shaokai Wang, Yizhuo Gu, Wei Zhang
Summary: This study improves the shear delamination resistance of composite laminate and enhances crack propagation resistance by using fine z-pins. The results demonstrate that z-pinning plays a significant role in improving interlaminar fracture toughness, and decreasing the z-pin diameter further enhances the resistance to crack propagation.
POLYMER COMPOSITES
(2022)
Article
Materials Science, Multidisciplinary
L. Huo, C. Kassapoglou, R. C. Alderliesten
Summary: In order to improve the current design approaches for composite structures, further investigation is needed on the damage interaction effects of composite materials under multiple out-of-plane concentrated loads. A combined experimental and numerical study was conducted, where two sequential out-of-plane quasi-static indentations were applied to fully clamped composite laminated panels. The results show that the second indentation delamination is more likely to propagate, indicating a decrease in the effective delamination threshold associated with microcracks ahead of the delamination front.
MATERIALS & DESIGN
(2023)
Article
Engineering, Manufacturing
Weigang Shi, Chao Zhang, Bo Wang, Mei Li, Chengyu Zhang
Summary: The wedge-loaded double cantilever beam (W-DCB) method was used in this study to evaluate the mode I interlaminar fracture toughness of two-dimensional (2D) continuous fiber-reinforced ceramic matrix composites (CMCs). A W-DCB model was established based on the elastic foundation theory, taking into account the axial force effect, shear effect, asymmetric propagation, and incomplete interlaminar contact. The friction effect was analyzed and measured using the theory of error transfer and a quasi-in-situ measurement method. The results demonstrate the accuracy of the W-DCB formula in conjunction with the experimental data, as verified by compliance curves, crack tip behaviors, and the cohesive zone of 2D CMCs. Furthermore, the calculated energy release rate (ERR) using the W-DCB theory was consistent with the measured data.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2023)
Article
Polymer Science
Mariana Domnica Stanciu, Silviu Marian Nastac, Ionut Tesula
Summary: This paper focuses on the sensitivity analysis of the effects of delamination of fiberglass-reinforced polymer composites in wind turbine blade structures using finite element analysis. The research reveals that delamination affects the stress states of the blade, with maximum stress values depending on the orientation of the composite layers.
Article
Mechanics
Yuhang Xiang, Zhongwei Zhang, Xiaoning Yang, Yuan Lin, Guokai Zhang, Chunming Song, Ziming Xiong
Summary: This paper investigates the effect of stitch density on the high-velocity impact damage inhibition and CAI strength of UHMWPE fiber composites. The results show that a smaller stitch space can significantly reduce delamination area and increase compressive load, but it may affect the CAI performance.
COMPOSITE STRUCTURES
(2024)
Article
Materials Science, Composites
Boxue Chen, Yi Zhang, Chi Mao, Yu Gan, Bolun Li, Haopeng Cai
Summary: This study fabricated rapid self-healing carbon fiber/epoxy composites by using core-shell nanofiber as a healing agent, which can efficiently fill and completely heal the damaged region.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Mechanics
Shu Kumabe, Shigeki Yashiro, Sota Onodera
Summary: Fracture of composite structures is often caused by delamination, making evaluation of interlaminar fracture toughness critical. A new test, the doubly end-notched tension (DENT) test, achieves stable mode II delamination growth in a simple tensile test. This study numerically investigated the influence of friction between delamination surfaces on the perceived energy release rate in the DENT test. The findings highlight the significance of frictional effects and propose a corrected equation to eliminate the frictional effect for evaluating the energy release rate in the DENT test.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Liaojun Yao, Jurui Liu, Zhangming Lyu, R. C. Alderliesten, Cui Hao, Chuanxi Ren, Licheng Guo
Summary: Carbon-fibre reinforced composites are prone to delamination, and fibre bridging is an important mechanism in shielding delamination. Micro-cracks initiated at the fibre-matrix interface gradually develop into micro-delaminations and eventually cause macro delamination propagation. The performance of bridging fibres can be divided into three stages, including bending, fibre-matrix peeling, and final breakage. The understanding of fibre bridging mechanisms is crucial for accurately representing and predicting delamination behavior in composite laminates.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Dingli Tian, Yu Gong, Yuting Gao, Luohuan Zou, Jianyu Zhang, Libin Zhao, Ning Hu
Summary: Significant R-curve effect is common in the mode I fracture of composite laminates, and accurate simulation of fracture with R-curve effect is crucial for damage tolerance design. This paper presents three phenomenological methods and a cohesive zone model to investigate the suitability of these methods for modeling delamination growth with significant R-curve effect. The accuracy, computational efficiency, and parameter acquisition of these methods are discussed, and it is shown that the cohesive zone model with multi-linear constitutive relation exhibits good accuracy in all cases studied.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Materials Science, Composites
Rui He, Longfei Cheng, Yidi Gao, Hao Cui, Yulong Li
Summary: This paper investigates the effect of in-plane shear stress on the fiber kinking compressive fracture toughness of laminates using compact compression specimens with off-axis fibers. The results show that in-plane shear stress increases the values of the R-curves, leading to an increase in energy dissipation. Microscopic morphology reveals the increasing splitting of fiber bundles and subsequent fiber compression failure as the off-axis angle of the fibers increases.
COMPOSITES SCIENCE AND TECHNOLOGY
(2023)
Article
Mechanics
Shigeki Yashiro, Tomohiro Yamasaki, Hiroto Nagai, Akinori Yoshimura
Summary: The study conducted an elastoplastic finite-element analysis on a new quasi-static mode II interlaminar fracture toughness test, the DENT test, to investigate the difference between the perceived energy release rate and the J-integral. It was found that the size of the plastic zone at the delamination crack tip played a significant role in the difference between the energy release rate and J-integral, and the difference in the DENT test was smaller compared to flexure-type tests. Compliance calibration method was applied to reduce the evaluation difference of the energy release rate in the elastoplastic analysis results of the DENT test.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
Thea I. W. Schnoor, Ulla Vainio, Li-Hua Shao, Erica T. Lilleodden, Martin Mueller, Andreas Schreyer, Karl Schulte, Bodo Fiedler
ADVANCED ENGINEERING MATERIALS
(2016)
Article
Materials Science, Composites
N. Emrah Merter, Gulnur Baser, Metin Tanoglu
JOURNAL OF COMPOSITE MATERIALS
(2016)
Article
Engineering, Mechanical
S. B. Basturk, M. Tanoglu, M. A. Cankaya, O. O. Egilmez
JOURNAL OF SANDWICH STRUCTURES & MATERIALS
(2016)
Correction
Chemistry, Physical
Matthias Mecklenburg, Daisuke Mizushima, Naoto Ohtake, Wolfgang Bauhofer, Bodo Fiedler, Karl Schulte
Article
Materials Science, Composites
Swetha Chandrasekaran, Wilfried V. Liebig, Matthias Mecklenburg, Bodo Fiedler, Dania Smazna, Rainer Adelung, Karl Schulte
COMPOSITES SCIENCE AND TECHNOLOGY
(2016)
Article
Materials Science, Composites
Serkan Kangal, Osman Kartav, Metin Tanoglu, Engin Aktas, H. Secil Artem
JOURNAL OF COMPOSITE MATERIALS
(2020)
Article
Materials Science, Composites
Bertan Beylergil, Metin Tanoglu, Engin Aktas
JOURNAL OF COMPOSITE MATERIALS
(2020)
Article
Materials Science, Composites
Hikmet Sinan Ustun, Ahmet Kaan Toksoy, Metin Tanoglu
Summary: The aim of this study is to enhance the ballistic performance of multi-layered fiber reinforced composite structures through a hybridization approach. The results showed that the energy absorbing capability and ballistic performance of the hybrid composite structures were similar or higher than those of ballistic fiber reinforced composites.
JOURNAL OF COMPOSITE MATERIALS
(2022)
Article
Polymer Science
Yusuf Can Uz, Metin Tanoglu
Summary: The aim of this study is to thermally characterize laboratory-scale carbon fiber/epoxy-based prepregs by incorporating single-wall carbon nanotubes (SWCNTs). Functionalized SWCNTs were used to improve dispersion characteristics, and carbon fiber reinforced prepregs containing different weight percentages of functionalized SWCNTs were prepared. FTIR analysis was conducted to identify new bonding groups, and cure kinetics of the prepregs were investigated using isoconversional methods.
HIGH PERFORMANCE POLYMERS
(2023)
Article
Materials Science, Composites
Gozde Esenoglu, Murat Barisik, Metin Tanoglu, Melisa Yeke, Ceren Turkdogan, Hande Iplikci, Seckin Martin, Kaan Nuhoglu, Engin Aktas, Serkan Dehneliler, Mehmet Erdem Iris
Summary: This study aims to improve the bonding behavior of fiber reinforced polymer composite joints by coating them with electrospun nanofibers on the prepreg surfaces. The experimental results show that the bonding strength of the joints is improved by about 40% with the presence of electrospun nanofibers, enhancing the adhesion performance of the composite joints.
JOURNAL OF COMPOSITE MATERIALS
(2022)
Article
Materials Science, Composites
Hande Iplikci, Murat Barisik, Ceren Turkdogan, Seckin Martin, Melisa Yeke, Kaan Nuhoglu, Gozde Esenoglu, Metin Tanoglu, Engin Aktas, Serkan Dehneliler, Mehmet Erdem Iris
Summary: The removal of contaminants and top polymer layer from the surface of Carbon-Fiber-Reinforced Polymer (CFRP) composites is crucial for achieving high-quality adhesive bonding with the reinforcing fiber constituents. Laser beam surface treatment offers a selective removal of the polymer matrix while preserving the fibers and improving wettability. However, the heterogeneous thermal properties of CFRP make it challenging to control laser ablation, as the absorbed laser energy is converted into heat and conducted through the fiber structures. This study characterizes the effects of scanning speed and laser power on nanosecond laser surface treatment, and determines the optimal processing parameters for complete removal of epoxy matrix without damaging the carbon fibers.
JOURNAL OF COMPOSITE MATERIALS
(2023)
Article
Materials Science, Characterization & Testing
Zeynep Ay Solak, Osman Kartav, Metin Tanoglu
Summary: This study investigates the effect of incorporating nano-sized fillers into an epoxy resin on the performance of cylindrical composites. The results show that the addition of SWCNTs does not significantly affect the viscosity of the resin or the wettability of the glass fiber. However, it improves the interlaminar shear strength and interlaminar fracture toughness of the filament wound composites.
POLYMERS & POLYMER COMPOSITES
(2022)
Article
Physics, Applied
Oleg Lupan, Vasile Postica, Janik Marx, Matthias Mecklenburg, Yogendra K. Mishra, Karl Schulte, Bodo Fiedler, Rainer Adelung
APPLIED PHYSICS LETTERS
(2017)
Article
Materials Science, Composites
Bertan Beylergil, Metin Tanoglu, Engin Aktas
ADVANCED COMPOSITES LETTERS
(2016)
Article
Chemistry, Multidisciplinary
Atike Ince Yardimci, Metin Tanoglu, Selahattin Yilmaz, Yusuf Selamet
TURKISH JOURNAL OF CHEMISTRY
(2020)
Article
Mechanics
Xiaolong Liu, Kelian Luo, Pengcheng Gao, Tao Cong, Xi Wang, Wenjing Wang
Summary: This paper investigates the formation mechanisms of the zig-zag crack region on the shattered rim of railway wheels. The zig-zag crack region, identified as a typical region for crack propagation in rolling contact fatigue behavior, was observed using scanning electron microscopy and transmission electron microscopy. The formation of the zig-zag morphology is attributed to the periodic deflection of the propagation path relative to the initial propagation plane, caused by the limited plastic deformation zone at the crack tip. Grain refinement and secondary cracks in the zig-zag crack region are a result of the large compressive and shear stresses induced by rolling contact loading.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Anastasia Iziumova, Aleksei Vshivkov, Ivan Panteleev, Virginia Mubassarova, Oleg Plekhov, Denis Davydov
Summary: The aim of this study was to investigate the correlation between structural, acoustic emission, and thermal characteristics of fatigue crack growth in titanium alloys. Cluster analysis of the acoustic emission signals revealed two different types of signals observed during the fatigue crack development. It was experimentally demonstrated that the stored energy tends to reach an asymptotic value at the final stage of fatigue crack growth and this is correlated with the twinning process intensification in titanium alloy Ti Grade 2. A correlation was assumed between the stages of change in heat flux, the cumulative energy of the first cluster of acoustic emission signals, and the crack length.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
M. Vieira de Carvalho, I. A. Rodrigues Lopes, F. M. Andrade Pires
Summary: This study investigates the numerical challenges of fracture mechanics models within implicit quasi-static frameworks and proposes an instability criterion. The ratio of cohesive to internal power is identified as a crucial factor. Two strategies for handling fracture problems with instabilities are discussed and a comparative assessment is performed. The study also examines more complex material responses, including transformation-induced plasticity effects.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Thomas Duminy, Aurelien Doitrand, Sylvain Meille
Summary: This study conducted in situ wedge splitting tests on millimeter-size PMMA samples and proposed a method to determine the material tensile strength and critical energy release rate using digital image correlation and a full finite element implementation of the coupled criterion.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Xin Chang, Xingyi Wang, Chunhe Yang, Yintong Guo, Yanghui Wan
Summary: The influence of cyclic thermal shock and high-temperature acid etching on the Mode I fracture of shale was investigated in this study. It was found that cyclic thermal shock severely degrades the strength and fracture toughness of shale, while high-temperature acid etching treatment improves the fracture toughness. These findings are valuable for optimizing process parameters to reduce initiation pressure in deep shale formations.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Liaojun Yao, Mingyue Chuai, Zhangming Lyu, Xiangming Chen, Licheng Guo, R. C. Alderliesten
Summary: Methods based on fracture mechanics have been widely used in fatigue delamination growth (FDG) characterization of composite laminates. This study proposes appropriate similitude parameters to represent FDG behavior with different R-ratios.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Zesheng Zang, Zhonghui Li, Yue Niu, Shan Yin
Summary: This study conducted experiments and recorded signals to investigate the fracture behavior and damage evolution characteristics of coal samples. The results showed that as loading proceeds, the stress, electric potential (EP), and acoustic emission (AE) values increase, and EP and AE signals are excited when stress drops. The fracture behavior of coal samples is altered by flaw inclination, and the destruction mode becomes increasingly complicated. The damage evolution characteristics of coal samples can be evaluated and analyzed by defining the coefficient of variation (CV value) of EP and the b value of AE.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Clotilde Berdin, Nathalie Prud'homme
Summary: In this study, zirconia layers with different fractions of tetragonal phase and thicknesses were tested for multi-cracking behavior. Cracks perpendicular to the tensile direction were observed, showing a blunting effect into the substrate. The ratio of crack spacing at saturation to layer thickness decreased as the layer thickness increased. Unit cell modeling was used to establish a relationship between crack spacing and layer strength, which fell within the bounds of Hu and Evans model and was found to be insensitive to the tetragonal zirconia fraction.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Huadong Zhang, Weichen Kong, Y. H. Liu, Yuh J. Chao
Summary: Williams' series expansion crack tip solution in linear elasticity is modified to include a uniform crack face pressure. Practical methods to calculate T-stress from near crack tip stresses are outlined. The analytical results are consistent with numerical results.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Jiahao Kong, Haoyue Han, Tao Wang, Guangyan Huang, Zhuo Zhuang
Summary: This paper introduces a phase-field model for polymer foam materials by combining the phase-field method with the crushable foam model. The model is calibrated using experimental data and successfully simulates the fracture processes of polyurethane under different loading conditions. The study is important for the engineering applications of polymer foam materials.
ENGINEERING FRACTURE MECHANICS
(2024)
