Article
Mechanics
Vitor Adriano, Wim De Waele, Eleine Cardon, Matthieu N. Boone, Stijn Hertele
Summary: The acceptance of volumetric weld imperfections can significantly impact the outcome of fracture toughness tests, even if the imperfections are within workmanship guidelines.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Jevan Furmanski
Summary: This study develops a new approach to measure tearing resistance and material mechanics during the tearing of polyethylene films, providing new insights into the tearing performance of these films.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Mechanics
Wen Liu, Ying Yu, Zhengxiang Zhang, Chengyang Liu, Yu Tong
Summary: Drop-weight testing was conducted to evaluate the dynamic impact-resistance properties of wood beams reinforced with carbon fiber reinforced polymers (CFRPs) compared to unreinforced wood beams. The results showed that reinforcement significantly improved impact resistance, and axial force also had a reinforcing effect. Additionally, the strengthening effect increased in the order of 1-ply CFRP sheet, CFRP plate, and 2 ply CFRP sheet.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Multidisciplinary
Yusheng Wang, Zhixiang Huang, Pengfei Zhu, Rui Zhu, Tianci Hu, Dahai Zhang, Dong Jiang
Summary: Digital image correlation (DIC) accurately measures subpixel displacement field based on speckle images. To address the high data transmission and storage requirements caused by extensive high-resolution images, a framework combining image compression techniques with DIC methods is proposed. The framework reduces the memory footprint of images while preserving the primary speckle features with subpixel errors.
Article
Engineering, Mechanical
Cheng Chen, Xudong Qian
Summary: This manuscript presents a non-contact approach to measure the J-integral resistance (J-R) curve for sidegrooved specimens using data measured solely from the digital image correlation (DIC). It establishes a fundamental relationship between the free-surface and throughthickness averaged J values, and demonstrates that side grooves impose trivial effects on the accuracy of the DIC J-R curve measurement.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Mechanics
Yoon Joo Na, Christopher L. Muhlstein
Summary: Commercial copy paper behaves like Al foils in terms of orthotropic constitutive behavior, with mode I crack tips developing quasistatic, fully plastic, steady-state conditions, including a positive offset stress due to fiber bridging. Reversed plastic zones dependent on orientation were observed in the crack wake, while transverse necking fracture processes were absent.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Multidisciplinary
Xueliang Gao, Ye Zhuang, Shu Liu
Summary: A novel method for measuring the rolling resistance coefficient of high-speed running tire is proposed, utilizing non-contact measurement and a high-speed stereo vision system to capture the transient deformation of the tire. By analyzing the relative displacement distribution and the relative flexible principal strain rate, the rolling resistance coefficient of high-speed running tire can be calculated.
Article
Mechanics
George Irven, Declan Carolan, Alexander Fergusson, John P. Dear
Summary: The study investigates the use of Digital Image Correlation (DIC) to examine microstructural damage in cross-ply laminates. The toughness of the epoxy polymer matrix significantly influences microcracking behavior in the near-surface plies. Experimental results show that using a tough epoxy polymer as the matrix increases the laminate moduli in the principal directions. DIC analysis provides valuable insights into the failure mechanism of cross-ply laminates, and the increase in modulus is attributed to the formation of microcracks in the transverse plies. Early matrix cracking around the tows can be detected by strain variations, and the use of toughened polymers delays the occurrence of this cracking.
COMPOSITE STRUCTURES
(2023)
Article
Mechanics
Juan Lu, Yafang Zhang, Libin Duan, Yongjie Huo, Hao Liu
Summary: This study investigated the impact behaviors of RC beams and CFRP-RC beams, finding that the introduction of CFRP can significantly reduce crack widths and deflections while improving impact resistance.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Chemistry, Analytical
Ruixiang Tang, Wenbing Chen, Yousong Wu, Hongbin Xiong, Banfu Yan
Summary: Digital image-correlation (DIC) algorithms heavily rely on accurate initial values from whole-pixel search algorithms for structural displacement monitoring. When the measured displacement is too large or exceeds the search domain, DIC algorithm's calculation time and memory consumption greatly increase, possibly leading to incorrect results. This study introduces two edge-detection algorithms, Canny and Zernike moments, in digital image-processing (DIP) to accurately determine structural displacement. Through numerical simulation, laboratory, and field tests, the study compares the accuracy and calculation speed of edge detection and DIC. Results show that edge detection is slightly less accurate and stable compared to the DIC algorithm. As the search domain of DIC increases, its calculation speed significantly decreases and is slower than the Canny and Zernike moment algorithms.
Article
Optics
Xuanshi Cheng, Shibin Wang, Huixin Wei, Linan Li, Zongze Huo, Chuanwei Li, Zhiyong Wang
Summary: Accurate deformation measurement is essential for researching the mechanical behavior of biological skin. This paper applies digital image correlation (DIC) to measure the deformation of biological skin using natural textures instead of artificial speckle. To achieve better calculation results, a speckle-free DIC (SF-DIC) method is proposed, which avoids artificial speckle and relies solely on natural textures. Two physical experiments are conducted to validate and demonstrate the effectiveness of the new methodology. The results show that SF-DIC provides reliable calculation results without the need for artificial speckle, making it a potential practical application in the study of biological skin and other materials with natural textures.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Engineering, Mechanical
Cheng Chen, Xudong Qian
Summary: This article presents a convenient method, using digital image correlation (DIC), to quantify the dynamic J-R curve. The DIC approach is validated through numerical and experimental results for SE(B) specimens, and it enables the measurement of the dynamic J-R curve during the DWTT. The proposed method allows for consistent measurement of J-integral and crack extension solely based on DIC displacement measurements on the specimen surface, facilitating direct comparison of fracture toughness under different strain rates. The results demonstrate an enhanced Mode-I fracture resistance of metallic materials under increased strain rates.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Multidisciplinary
Ruiyang Wang, Xinwei Zhang, Dahai Li
Summary: Traditional phase measuring deflectometry and digital image correlation based deflectometry have limitations in dynamic measurement, while our proposed single-shot dynamic speckle deflectometry offers a solution with validated accuracy and robustness through numerical simulations and practical measurements.
Article
Mechanics
Rijin He, Xiaoying Sun, Yue Wu, Guowen Tang, Valter Carvelli
Summary: This study experimentally investigated the crack tearing properties of PVC coated fabrics, revealing that the initial crack length has an impact on tearing residual strength, while the variation of crack orientation has a negligible effect.
COMPOSITE STRUCTURES
(2021)
Article
Optics
Zhenyu Jiang
Summary: OpenCorr is an open source C++ library that provides full-function modules of 2D and stereo DIC, as well as digital volume correlation (DVC) for research and development of DIC technology. Its sophisticated design makes it developer-friendly, allowing users to quickly create DIC software for specific applications and develop new algorithms. The library's computation speed has been evaluated and shown to be superior. OpenCorr has gained significant interest from the academic and industrial communities, driving the advancement and spread of DIC technology.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Mechanics
Vitor Adriano, Wim De Waele, Eleine Cardon, Matthieu N. Boone, Stijn Hertele
Summary: The acceptance of volumetric weld imperfections can significantly impact the outcome of fracture toughness tests, even if the imperfections are within workmanship guidelines.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Mechanics
Kris Hectors, Wim De Waele
Summary: This paper presents an X-FEM based iterative framework for numerical simulation of three-dimensional fatigue crack propagation. B-spline curves and surfaces are used to accurately describe the crack geometry, and a new crack front extension method based on the Moller-Trumbore algorithm is introduced. Good agreement between numerical and experimental results validates the effectiveness of the method.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Civil
Mojtaba Khayatazad, Matthias Honhon, Wim De Waele
Summary: This paper introduces a corrosion detection approach based on an artificial neural network (ANN) with a small training dataset size. The proposed ANN outperforms existing image processing algorithms in terms of both speed and accuracy.
STRUCTURE AND INFRASTRUCTURE ENGINEERING
(2023)
Article
Automation & Control Systems
Rafael Nunes, Koen Faes, Sylvia De Meester, Wim De Waele, Andrzej Kubit
Summary: This paper analyzes the influence of ultrasonic welding parameters on joint strength and quality, and determines the optimal process parameters through experimental research.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Robin Depraetere, Wim De Waele, Margo Cauwels, Tom Depover, Kim Verbeken, Matthieu Boone, Stijn Hertele
Summary: An experimental study was conducted to investigate the plastic anisotropy and ductile fracture behavior of API 5L X70 pipeline steel with and without hydrogen charging. The presence of hydrogen was found to accelerate ductile damage development and fracture, especially under higher stress triaxiality. These results are important for the development of numerical models to describe hydrogen embrittlement in high-strength low-alloy steel.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Engineering, Mechanical
Gopalakrishnan Ravi, Wim De Waele, Ksenija Nikolic, Roumen Petrov, Stijn Hertel
Summary: Bearing failure can occur in various machinery and is often caused by rolling contact fatigue (RCF) triggered by damage initiation at non-metallic inclusions (NMI's). This study focuses on numerically investigating the impact of NMI features and bonding with the steel matrix on damage initiation lifetime. Simulation results indicate an immediate debonding at the matrix-inclusion interface followed by accelerated crack initiation. The depth for damage initiation shifts towards the surface with increasing friction coefficient between roller and raceway, and larger inclusions demonstrate earlier damage initiation.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Manufacturing
Koen Faes, Rafael Nunes, Sylvia De Meester, Wim De Waele, Felice Rubino, Pierpaolo Carlone
Summary: Ultrasonic welding is a solid-state welding process that uses high frequency vibration energy to generate internal friction and local heat to join workpieces. It is particularly attractive for industries such as electrical/electronic, automotive, aerospace, appliance, and medical products due to its short welding time, low heat input, absence of fumes/sparks/flames, and automation capacity. The main challenge in these industries is the poor weld quality caused by improper selection of weld parameters. This study investigates the influence of welding time, pressure, and vibration amplitude on joint characteristics and weld strength when joining 0.3 mm thick copper sheets using ultrasonic welding. The results show that welding time is the most significant factor affecting energy absorption during welding, followed by pressure and amplitude. Shear strength is mainly influenced by amplitude, while the other parameters have limited effect. Regardless of the welding configuration, most welds exhibit a failure load higher than the base material, demonstrating the feasibility of ultrasonic welding for joining copper sheets.
JOURNAL OF MANUFACTURING AND MATERIALS PROCESSING
(2023)
Article
Engineering, Mechanical
Hasan Saeed, Somsubhro Chaudhuri, Wim De Waele
Summary: This article proposes a novel front face strain compliance technique for accurately quantifying the short fatigue crack growth stage. This method is validated by numerical analysis and experiments, and a compliance equation based on the front face strain is presented.
JOURNAL OF STRAIN ANALYSIS FOR ENGINEERING DESIGN
(2023)
Article
Materials Science, Characterization & Testing
Pankaj R. Jaiswal, R. Iyer Kumar, Thibault Juwet, Geert Luyckx, Cedric Verhaeghe, Wim De Waele
Summary: This paper studies the strength and deformation of full-scale adhesively bonded multi-material joints. Four joints with a thick layer of methyl methacrylate adhesive (MMA) were manufactured in shipyard conditions. Two specimens had cracks introduced at the steel-adhesive and composite-adhesive interfaces. Tensile testing and stepwise loading/unloading were performed on the specimens, and strain measurements were conducted using digital image correlation (DIC) and fibre Bragg (FBG) sensors. All specimens failed due to delamination of the composite panel near the composite-adhesive interface.
Article
Chemistry, Physical
Dibakor Boruah, Nele Dewagtere, Bilal Ahmad, Rafael Nunes, Jeroen Tacq, Xiang Zhang, Hua Guo, Wim Verlinde, Wim De Waele
Summary: This study demonstrates the capability of the DIC technique in evaluating full-field residual stresses in WAAM components. The bending deformation during unclamping of WAAM parts was monitored using DIC, and the residual stresses were calculated from the captured strain field. The results were verified with an analytical model and validated using established residual stress measurement techniques.
Article
Materials Science, Multidisciplinary
Kris Hectors, Dennis Vanspeybrouck, Jelle Plets, Quinten Bouckaert, Wim De Waele
Summary: This work focuses on the lack of verification and comparison of existing fatigue damage accumulation and life prediction models using large and well-documented experiment datasets. A comprehensive dataset was generated by conducting several valid experiments, which can be used as a benchmark for existing models. The study compared five (non)linear fatigue damage and life prediction models using the obtained dataset, revealing the strong dependence of model performance on material dataset and loading sequence. It emphasizes the importance of verifying models with diverse independent datasets to overcome biases exhibited by existing models.
Article
Nanoscience & Nanotechnology
Margo Cauwels, Robin Depraetere, Wim De Waele, Stijn Hertele, Kim Verbeken, Tom Depover
Summary: This study investigates the hydrogen-assisted ductility loss of API 5L X70 pipeline steel and finds that the steel becomes more brittle after hydrogen charging. Notched samples are more susceptible to hydrogen embrittlement compared to unnotched samples, and hydrogen signatures in the form of fisheyes and quasi-cleavage are detected on the fracture surface.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Characterization & Testing
Pankaj R. Jaiswal, Rahul Iyer Kumar, Franz Bormann, Thibault Juwet, Geert Luyckx, Luc Mouton, Cedric Verhaeghe, Wim De Waele
Summary: This study investigates the fatigue behavior and static strength of full-scale adhesively bonded steel-composite joints. The experimental results show that the strain values in the adhesive bondlines are higher on the gripped sides due to the asymmetrical design of the steel brackets. All specimens exhibit significantly higher shear strength than the design values. Fibre Bragg sensors are able to detect damage onset in tensile tested specimens.
Review
Materials Science, Multidisciplinary
Rafael Nunes, Koen Faes, Wim De Waele, Aude Simar, Wim Verlinde, Matthieu Lezaack, Wout Sneyers, Julius Arnhold
Summary: This paper reviews the literature on the weldability of AM aluminum alloys and analyzes the evolution of microstructure and mechanical properties. The study reveals a clear relationship between the AM technology used for component manufacturing and the physical principles of the joining process.
Article
Engineering, Manufacturing
Rafael Gomes Nunes Silva, Sylvia De Meester, Koen Faes, Wim De Waele
Summary: This study evaluates the impact of process parameters on ultrasonic spot weld quality of copper-aluminium plates and achieves satisfactory weld quality by optimizing the parameters.
JOURNAL OF MANUFACTURING AND MATERIALS PROCESSING
(2022)
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)
