Article
Mechanics
Reza Sepasdar, Maryam Shakiba
Summary: This study uses a nonlinear cohesive interface-enriched generalized finite element method, along with elastic, elasto-plastic damage model, and cohesive zone model, to investigate the effects of transverse crack density, delamination, and intra-ply stress redistribution on the performance of composite laminates. The developed framework is validated against experimental results and the correlation between different stages of failure and the studied parameters is discussed.
COMPOSITE STRUCTURES
(2022)
Article
Chemistry, Physical
Zeina Hamam, Nathalie Godin, Pascal Reynaud, Claudio Fusco, Nicolas Carrere, Aurelien Doitrand
Summary: This study investigates the acoustic emission induced by transverse cracking in carbon fiber/epoxy matrix composite laminates through experimental and numerical analysis. The influence of sensor type, specimen thickness, and ply stacking sequence is examined. The study reveals that the frequency content corresponding to the same damage mechanism varies significantly depending on the sensor and stacking sequence. However, the frequency centroid is not solely dependent on the ply thickness except for inner ply cracking. Outer ply cracking exhibits low-frequency signals that are not greatly influenced by the ply thickness, while inner ply cracking shows higher frequency content that is more dependent on the ply thickness. Experimental frequency peaks and centroids are well captured by numerical simulations for different ply thicknesses.
Article
Materials Science, Multidisciplinary
Ning An, Qilong Jia, Hao Jin, Xiaofei Ma, Jinxiong Zhou
Summary: This paper presents a bottom-up computational strategy that connects the microscopic properties of composites with their macroscopic behavior. It develops a user-friendly plug-in tool in Abaqus to estimate the effective viscoelastic properties of composites and successfully simulates the deployment performance of composite structures.
MATERIALS & DESIGN
(2022)
Article
Materials Science, Composites
M. J. Mohammad Fikry, Vladimir Vinogradov, Shinji Ogihara
Summary: Experimental observations show that in unidirectional laminates, resin pockets can develop multiple cracks before delamination occurs, with cracks typically forming within the resin pocket rather than at the interfaces with the discontinuous ply. The curved crack paths are governed by the distribution of maximum principle stress, while crack locations are best determined using the principle of maximum energy release rate. This unintuitive cracking behavior is explained by higher residual stresses due to chemical shrinkage of the resin during curing in the confined conditions of the pocket.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Mechanics
Weiwei Wang, Han Wang, Shaohua Fei, Huiyue Dong, Yinglin Ke
Summary: This paper proposes a new concurrent multiscale unit cell model to investigate the in-plane micro-damage evolution of Z-pinned composite laminates (ZCL). The research indicates that in-plane micro-damage initiates from the interface between Z-pin and matrix, with stress concentration and higher local fiber volume fraction playing a major role.
COMPOSITE STRUCTURES
(2022)
Article
Mechanics
Shengnan Zhang, Yingjie Xu, Weihong Zhang, Xinyu Hui
Summary: A novel micro-mechanical modeling approach was developed to predict the partially debonding of Z-pin reinforced composite laminates after the cure process. Numerical simulation results showed that residual stress concentration mainly occurred in the interphase, potentially resulting in interfacial cracking around the Z-pin.
COMPOSITE STRUCTURES
(2022)
Article
Materials Science, Composites
M. Simonetto, P. A. Carraro, L. Maragoni, M. Quaresimin
Summary: This work analyzes the transverse crack initiation, propagation, and crack density evolution in cross-ply laminates under two-stage block loadings. A theoretical formulation for cracking probability under variable amplitude blocks is obtained based on the linear damage accumulation rule. The comparison between experimental results and predictions validates the adequacy of the linear damage accumulation rule for crack initiation under block loadings. Investigations of damage evolution at the micro-scale provide mechanistic support to this approach.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Dirk Lukowsky, Mark Meder
Summary: The European standard EN 438-2 (2019) provides a method to assess the resistance to cracking of high-pressure laminate (HPL). However, the standard test did not reach moisture equilibrium, leading to prolonged testing and further investigation into parameters and influencing factors. The composition of the laminate was identified as the main influence on cracking resistance.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Chemical
Fidele M. Abedi, Yuxiang Liu, Pawan S. Takhar
Summary: The distribution of moisture, temperature, strain, and stress during convective drying of bananas was studied using a mathematical model based on hybrid mixture theory. The model was validated against experimental data and used to evaluate the effectiveness of a fan on/off strategy in reducing stress cracking. The results showed that intermittent fan operation reduced stress cracking in bananas compared to continuous drying.
Article
Mechanics
Liyong Jia, Chen Zhang, Zhiyong Hu, Peihao Song, Long Yu, Changhong Tang
Summary: In this study, the XFEM method is used to predict failure in composite laminates by determining the normal direction of fracture surfaces under different failure modes. A user-defined FORTRAN subroutine is implemented for Abaqus/Standard solver to model damage initiation and crack propagation, showing that XFEM can effectively predict crack initiation and propagation with smoother matrix failure paths.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Manufacturing
M. L. Velasco, E. Correa, S. Sanchez-Carmona, F. Paris
Summary: This study investigates the various damages that may occur in the laminate when increasing the thickness of the layers, and correlates the findings with experimental observations of the scale effect.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2023)
Article
Materials Science, Multidisciplinary
Quan Zhang, Stephan Rudykh
Summary: This study investigates the magneto-mechanical behavior of periodic laminates made of hard-magnetic active elastomers (HMAEs) and examines the induced deformation and shear wave propagation in HMAE laminates under a magnetic field. The results show that remanent magnetization can lead to compressive deformations and tunable shear wave band gaps.
MECHANICS OF MATERIALS
(2022)
Article
Polymer Science
Muhammad Akhsin Muflikhun, Bodo Fiedler
Summary: This study explores the failure and surface characteristics of Glass Fiber-Reinforced Polymers (GFRP). The angle of the GFRP UD laminates' position significantly impacts the system's failure, with preliminary failure occurring in the [0/90](S) laminates. The [90/0](S) laminates have a higher strength and different surface roughness and hardness compared to the [0/90](S) laminates.
Article
Materials Science, Composites
Nisha Sharma, Kalyan Kumar Singh
Summary: This study investigates the effect of interchanging (0 degrees/90 degrees) and (+/-45 degrees) angle ply on the properties of eight-layer symmetric and asymmetric woven glass fiber reinforced composites through flexure and fatigue tests. The flexural and fatigue behavior of glass fiber-reinforced polymer laminates were also analyzed. The experimental results demonstrate that the symmetric laminate exhibits higher flexural strength (458.09 MPa) and fatigue life compared to the asymmetric A (352.70 MPa) and asymmetric B (272.89 MPa) laminates.
POLYMER COMPOSITES
(2023)
Article
Engineering, Manufacturing
P. A. Carraro, L. Maragoni, M. Quaresimin
Summary: This study conducted tension-compression and compression-compression fatigue tests on glass/epoxy cross-ply laminates under different load ratios, revealing three different damage scenarios and highlighting the role of Local Hydrostatic Stress in controlling damage evolution.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2022)