Behavior Of Composite Materials Research Articles

Metrological assessment of the carbon tubes behavior under thermal variation for the compensation of 3D devices

Abstract Composite materials are increasingly used in 3D metrology, especially for portable measuring devices such as articulated arm coordinate measuring machines (AACMM), 3D scanners, and ball bars. Their use is justified by their interesting mechanical properties including their low density, good rigidity, and especially their light weight, which makes them ideal for portable devices, that are meant to be often transported by the user. However, due to their complex composition, the characterization of the thermal behavior of composite materials remains complicated compared to standard materials and is nowadays an active research subject. In fact, the coefficient of thermal expansion of composite materials is dependent of the very specific composition of the composite material considered. Hence, it is function of several parameters such as the orientation of the fibers, the fiber volume fraction, the ply sequence, the cooling rate, etc.
In the other hand, in 3D metrology, and especially in portable 3D metrology, determining the expansion coefficient of the different part of the measurement devices used is necessary. In fact, the portable measurement machines are often integrated and used directly on the shop floor, where the thermal variations can be important and then heavily impact the measurements results. in some cases, the lack of knowledge of the coefficient of thermal expansion of the composite materials that compose the portable measuring machine can significantly increase the measurement uncertainty.

An efficient finite element mesh generation methodology based on μCT images of multi-layer woven composites

High-fidelity models are essential for accurate finite element (FE) simulations of composite material behavior. This paper proposes an efficient meshing methodology based on micro-Computed Tomography (μCT) images. U-Net convolutional neural network was used for image segmentation. Connected yarns were then separated using an improved procedure based on watershed algorithm and geometric transformations. The proposed Constrained Delaunay-Advancing Front Technique (CD-AFT) surface reconstruction algorithm extracts point cloud of yarns from segmented images and outputs high-quality and smooth orientable manifold watertight triangulated surface. Intersecting meshes of yarns are separated through node position detection and Laplacian moving. Experimental results show that proposed methodology is capable of accomplishing mesh generation for different mesh sizes. Compared with commercial software, it has obvious advantages in mesh quality and size control. Since the proposed method operates independently of commercial software and manual operation, it facilitates the automated generation of numerous high-fidelity models from μCT images for FE simulations.

Development of lightweight and high-strength glass fiber and natural fiber hybrid composites using VARTM technique

This research paper presents the synthesis of Glass Fiber Reinforced Plastic (GFRP) and Natural Fiber Hybrid Composites (NFHC) utilizing Vacuum-Assisted Resin Transfer Molding (VARTM) techniques. Jute and flax fibers were strategically selected for their unique properties and potential synergistic effects when combined with glass fibers. The study systematically evaluates the influence of natural fiber incorporation on the mechanical performance of the composites, focusing on critical factors such as fiber type, orientation, and resin selection. A series of meticulously crafted laminate configurations were employed. These included combinations of glass and jute fibers (GJG, GJGJG), glass and flax fibers (GFG, GFGFG), and a reference laminate composed solely of glass fibers (GGGGG). The mechanical characterization involved rigorous Izod impact testing, hardness assessments, and water absorption tests to provide a detailed understanding of behavior of composite material. The results reveal that the incorporation of jute fibers resulted in a significant enhancement of impact resistance of up to 59 % compared to GFG laminates and hardness. Water absorption varied across the laminates, with GGGGG exhibiting the lowest value of 0.054 %. Scanning Electron Microscopy (SEM) was employed to gain valuable insights into the critical fiber-matrix interaction and microstructure of the composites, further elucidating the observed mechanical properties. These findings pave the way for lightweight, high-strength composites ideal for engineering applications, particularly automotive mono leaf springs. The resulting weight reduction promises significant gains in fuel efficiency and vehicle performance, advancing sustainable materials with exceptional mechanics.

Numerical and experimental investigation of quasi-static indentation response of PVC foam sandwich and GFRP laminated composites

AbstractComposite materials are vulnerable to impacts that may occur during their use. Such transverse loads represent a significant threat to these materials because they can cause damage that is difficult to detect. Thus, understanding the mechanical behavior of composite materials during impacts is crucial for improving their damage resistance. Therefore, this study investigates the response of two commonly used composite panels in maritime transportation—a PVC core sandwich composite and a laminated GFRP composite—under quasi-static indentation (QSI). Using numerical simulations with Abaqus/Explicit, this investigation aims to anticipate mechanical characteristics and damage patterns during low-velocity impact. Results show a strong correlation between numerical and experimental data. The force-displacement curves aid in understanding damage sequences, with predicted maximum loads at 1.43% and 6.45% accuracy for laminated and sandwich composites. Both exhibit significant damage, including permanent indentation, matrix cracks, fiber fractures, and prevalent delamination around the impact point.

A finite crack growth energy release rate for interlaminar fracture analysis of composite material at different temperatures

The interlaminar fracture toughness of unidirectional fiber reinforced polymer composite material is temperature and crack growth history dependence. The non-constant interlaminar fracture toughness challenges the wide application of the linear elastic fracture mechanics-based approach for analyzing the interlaminar crack growth in composite material and structures. In addition, a quantitative relationship between the ductility of the matrix and interlaminar fracture toughness of the fiber reinforced composite is still highly desirable. In this paper, both pure resin and composite double cantilever beam (DCB) are tested at different temperatures. A finite crack growth energy release rate is used to analyze the interlaminar crack growth behavior of composite material at different temperatures. The plasticity of the composite DCB is modeled by Hill’s anisotropic plasticity, with the properties determined from multiscale analyses. It is found that a single constant finite growth energy release rate can well predict the interlaminar mode I crack growth of composite material at different temperatures. The roles of the ductility of matrix, thickness of the DCB, and crack growth history on the interlaminar mode I fracture toughness of composite material are quantitatively determined by using the present method.

Dynamic Behavior and Permanent Indentation in S2-Glass Woven Fabric Reinforced Polymer Composites under Impact: Experimentation and High-Fidelity Modeling

This paper studies the behavior of S2-glass woven fabric reinforced polymer composite under low-velocity impact at 18–110 J energy. A macro-homogeneous finite element model for the prediction of their response is implemented, considering the non-linear material behavior and intralaminar and interlaminar failure modes for the prediction of impact damage. The model accurately predicted the permanent indentation caused by impact. By applying the Ramberg-Osgood formulation, different initial stiffness values are examined to assess the post-impact unloading response. This approach reveals the significant role of initial stiffness in inelastic strain accumulation and its consequent effect on permanent indentation depth. A higher initial stiffness correlates with increased inelastic strain, influencing the impactor rebound and resulting in greater permanent indentation. By accurately predicting permanent indentation, and damage accumulation for different impact energies, this study contributes to a better understanding of the impact behavior of composite materials, thereby promoting their wider application.

Ballistic impact resistance and flexural performance of natural basalt fiber with carbon and glass fibers in inter‐ply hybrid composites

AbstractThe ballistic and flexural behaviors of basalt (natural fabric), carbon, glass fiber, and their hybrid composites, were investigated in this study. The main objective of the paper was the addition of natural basalt fiber to the carbon and glass fibers with inter‐ply hybrid sequences to search for possible usage to the ballistic loads carrying structures. The composite and hybrid composite plates produced nine layers with cross‐ply stacking sequences ([0/90]9). The ballistic impact tests were conducted using a specially designed ballistic test setup and the flexural tests were performed through the standard three‐point bending test. The results showed that basalt/epoxy absorbed the most energy under ballistic loading among all models. It was observed that the basalt‐glass‐basalt/epoxy (BGB) hybrid composite had an energy absorption capacity very close to the basalt/epoxy composite. When BGB and carbon‐glass‐carbon/epoxy (CGC) hybrid models were compared, the energy absorption capacity of CGC was 62.7% less than BGB. Unlike the ballistic test result, basalt/epoxy had the lowest flexural strength, while carbon/epoxy had the highest flexural strength. Among the hybrid models, it was seen that BGB had the lowest flexural strength, while CGC had the highest flexural strength. The flexural strength of the CGC is 38% higher than BGB. The study found that basalt fiber has high ballistic resistance, whether alone or when combined with commonly used fibers. It also suggests that basalt fiber is a promising candidate for future research and development in the field of protective materials.Highlights Basalt (natural fabric) composite materials behavior. Hybridization of basalt with carbon and glass. Target plates damage resistance according to applied ballistic loads. Target plates damage resistance according to applied flexural loads. Non‐hybrid and hybrid composites plates comparisons.

Failure Analysis and Fatigue Behavior of Natural Fibers Reinforced Composite Materials under Cyclic Loading

This research investigates the failure analysis and fatigue behavior of composite materials reinforced with a combination of glass fiber, sisal fiber under cyclic loading conditions. The study aims to elucidate the synergistic effects of these diverse natural fibers in enhancing the mechanical properties and fatigue resistance of the composite materials. Experimental methods, including mechanical testing and microscopic analysis, are employed to discern the individual contributions of each fiber type and their combined influence on failure modes and fatigue life. The project seeks to provide valuable insights into the optimal integration of glass, sisal to achieve a balanced composite material that exhibits superior durability and performance. The outcomes of this research contribute not only to the advancement of natural fibers composites but also offer practical guidelines for designing resilient materials for various engineering applications.

On the fatigue behaviour of epoxy-based nanostructured composite materials

Epoxy composites and nanocomposites enable the creation of high-performance structures and innovative designs. However, there is limited research focused on their fatigue characterization. The purpose of this study is to analyze the fatigue resistance results of nanostructured composite materials made with an epoxy matrix of Diglycidyl Ether of Bisphenol F and 9,9-bis(3-chloro-4-aminophenyl) fluorine (DGEBF-CAF) reinforced with 5%wt of elastomeric nanoparticles with an average diameter of 200 nm. The tests are conducted at variable load and frequency using Rotating Bending (R-B) and Tensile-Tensile (T-T) tests, and the results are compared to those obtained with pure resin. The occurrence of thermal fatigue phenomena during the tests is monitored using a thermal camera. The results confirm that pure epoxy resin exhibits poor crack propagation resistance due to its low ductility and toughness, and the introduction of a second phase leads to an improvement of approximately 3 times in T-T tests and 5 times in R-B tests.

Assessment of the effect of processing parameters on peel failure of laser-assisted automated fiber placed thermoplastic composites

In this study, thermoplastic composites are fabricated using laser-assisted automated fiber placement, focusing on the influence of compaction force, roller head speed, and temperature. Employing wedge peel testing, digital and electron microscopy, and probabilistic machine learning, the research examines how these parameters affect mechanical performance and failure. Key observations include increased bonding area and peel force with higher processing temperatures, while greater compaction force introduces more variability in bonding and peel strength. Roller head speed shows minimal impact. The study effectively links processing parameters with wedge peel failure, illustrating the complex interactions in composite material behavior.

Study on the bending and dimensional behavior of honeycomb latticed ONYX composite material

Engineering, architecture, and transportation all use honeycomb structures in various ways. Latticing, made possible by additive manufacturing (AM), may significantly speed up the creation of adaptable structures. The current study focuses on assessing the impact of various three-dimensional (3D)-printing features on the flexural behavior and dimensional studies of the honeycomb latticed micro-carbon fiber reinforced nylon (ONYX) material. The experiment is performed by varying the levels of 3D-printing features like layer thickness (LT), infill geometry (IG), build direction (BD), shell count (SC), and infill percentage (IP) to measure the bending strength, length deviation, and lattice surface morphology variation. The experimental results show that, the peak flexural strength of 79.84 MPa is attained with specimen fabricated at 0.1 mm LT, 50% IP, 0° BD, rectilinear IG, and SC of 3. And moreover, these respective 3D-printing feature levels resulted in an improved surface morphology on the latticed specimens. The length deviation results clearly depict that specimen fabricated at lower LT of 0.1 mm, higher SC of 3, rectilinear IG, 0° BD, and higher IP of 50% consequences in accurate profile with a lower length deviation of 0.117 mm. The fractography results clearly implies that the 0° oriented latticed ONYX composite results in a progressive fracture and results in higher bending stress. On the other hand, the 45° and 90° oriented latticed ONYX materials undergo tilted fracture and perpendicular mode of fracture, respectively. From that it is concluded that, the triangular-shaped honeycomb latticed ONYX materials are suitable for the development of brackets for the portable cameras, medical, and dental appliances like prosthetics for lightweight splints in postsurgery.

Solver-free reduced order homogenization for nonlinear periodic heterogeneous media

Reduced-order homogenization (ROH) and related methods are important computational tools for simulating the material behavior of composites. These methods generally sacrifice accuracy in exchange for superior computational efficiency, relative to methods such as classical computational homogenization (CCH). In this study, building on the recently developed solver-free CCH, we propose a fine-scale solver-free reduced order homogenization approach that avoids solving the fine-scale equilibrium equations and approximates the phase-average eigenstrains by sampling the fine-scale eigenstrain at a small number of points. The proposed method, which we call solver-free ROH, works by pre-computing history-dependent eigenstrain influence function tensors and sampling point contribution factors based on training data from a small set of CCH simulations. Then, during the online stage of the computation, phase-average eigenstrains are computed from sampling point eigenstrains and used to compute homogenized stresses and strains. Focusing on small-deformation problems, this paper formulates and verifies the solver-free ROH approach for nonlinear periodic heterogeneous media. First, in the formulation, we delineate a sampling point approximation of the phase eigenstrains and describe the use of this approximation within the coarse-scale stress update. Next, we verify the solver-free ROH using loading cases outside the training data set. Finally, we use the proposed method to simulate a multilayer composite plate in three point bending (3pt-bend) and open hole tension (OHT), demonstrating the method’s efficiency and accuracy relative to the CCH.

Characterization of Microstructure, Optical Properties, and Mechanical Behavior of a Temporary 3D Printing Resin: Impact of Post-Curing Time.

The present study aimed to characterize the microstructure of a temporary 3D printing polymer-based composite material (Resilab Temp), evaluating its optical properties and mechanical behavior according to different post-curing times. For the analysis of the surface microstructure and establishment of the best printing pattern, samples in bar format following ISO 4049 (25 × 10 × 3 mm) were designed in CAD software (Rhinoceros 6.0), printed on a W3D printer (Wilcos), and light-cured in Anycubic Photon for different lengths of time (no post-curing, 16 min, 32 min, and 60 min). For the structural characterization, analyses were carried out using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The mechanical behavior of this polymer-based composite material was determined based on flexural strength tests and Knoop microhardness. Color and translucency analysis were performed using a spectrophotometer (VITA Easy Shade Advanced 4.0), which was then evaluated in CIELab, using gray, black, and white backgrounds. All analyses were performed immediately after making the samples and repeated after thermal aging over two thousand cycles (5-55 °C). The results obtained were statistically analyzed with a significance level of 5%. FT-IR analysis showed about a 46% degree of conversion on the surface and 37% in the center of the resin sample. The flexural strength was higher for the groups polymerized for 32 min and 1 h, while the Knoop microhardness did not show a statistical difference between the groups. Color and translucency analysis also did not show statistical differences between groups. According to all of the analyses carried out in this study, for the evaluated material, a post-polymerization time of 1 h should be suggested to improve the mechanical performance of 3D-printed devices.

Uncertainty quantification for viscoelastic composite materials using time-separated stochastic mechanics

With the growing use of composite materials, the need for high-fidelity simulation techniques of the related behavior increases. One important aspect to take into account is the uncertainty of the response due to fluctuations of the material parameters of the constituent materials of the homogenized composite. This inherent randomness leads to stochastic stresses on the microscale and uncertain macroscale response. Until now, the viscoelastic response of the matrix material seriously hindered the application of efficient methods to predict the composite material behavior. In this work, a novel method based on the time-separated stochastic mechanics (TSM) is developed to address this problem. We present how the uncertainty of the microscale stresses of a representative volume element and the homogenized macroscale stresses can be approximated with a low number of deterministic finite element simulations. Quantities of interest are the expectation, standard deviation, and the probability distribution function of the stresses on micro- and macroscale. The results showcase that the TSM is able to approximate the reference results very well at a minimal fraction of the computational cost needed for Monte Carlo simulations.

Thermal properties of a raw earth-flax fibers building material

The aim of this paper is to investigate the thermal behavior of composite building materials comprised of silt and flax fibers, considering various initial conditions. The experiments were conducted on flax fibers alone, examining factors such as moisture content variation, fibers arrangement, and density. Subsequently, the thermal properties of the earth-flax fiber composite were studied, taking into account the influence of water content and fibers mass content. The thermal properties of both flax fibers and raw earth-flax fibers composite specimens were determined using the experimental unsteady-state method. The results indicate that the thermal conductivity and heat capacity of flax fibers increase with density, temperature, and moisture content. Regardless of fibers density and arrangement of fibers, linear relationships have been established for both thermal conductivity and heat capacity as functions of temperature. Additionally, it was demonstrated that the heat capacity and the thermal conductivity increase with water content, regardless of the percentage of added fibers. Moreover, mixing randomly flax fibers with compacted raw earth material has improved the thermal properties of the composite. This improvement pertains to its insulating capacity, ability to store heat, and, subsequently, its contribution to the thermal comfort provided by such earth composite material when used as a building material.

Investigation on tribological behaviour of copper-free composite friction material under dry sliding at high-temperature

ABSTRACT This research uses a rotary pin-on-disc tribometer to explore the friction and wear behaviour of a copper-free semi-metallic friction composite over various operating temperatures, 25 °C, 150 °C, 250 °C, 350 °C, and 450 °C. The tribological performance of copper-free semi-metallic specimens is significantly affected by heat degradation. It was found that at 450 °C, severe wear of the pin specimen occurred. The friction layer coverage gradually decreased at ≥ 250 °C. The composite pin’s wear rate was found to increase 13.26 times from 450 °C to 25 °C, whereas the disc wear rate at 450 °C was 0.86 times the wear rate at 25 °C for the loading condition of 60 N load, 2.09 m/s sliding velocity and 6283 m sliding distance. Micro-ploughing was the primary wear process below and at 150 °C, whereas groove development, delamination, and severe adhesion dominated above 150 °C.

Classification, applications, and impact behavior of composite materials: A review

Composites are increasingly preferred in industrial, medical, and sporting applications due to their exceptional mechanical, electrical, thermal, and physical properties, as well as their low weight and investment costs, particularly in medical, electronics, aerospace, and automotive sectors. Impact damage to composite materials is a significant design issue, necessitating a thorough understanding of how these materials break down and fail under impact loads to ensure reliable and cost-effective design. This paper uses both experimental and numerical methods to present an in-depth review of the impact properties of composite materials.

Wetting, droplet evaporation and corrosion behavior of various composite and textured materials

Experimental studies were conducted on the evaporation rate of a droplet located on the surfaces of various composite and textured materials with different wettability at varying surface temperatures. The maximum droplet evaporation rate was recorded on a textured Cu–SiC composite material with superhydrophilic properties. The minimum droplet evaporation rate corresponded to a superhydrophobic AlMg3 substrate obtained using laser texturing with subsequent hydrophobization procedure. An increase in surface temperature led to a significant deterioration of hydrophobicity for a superhydrophobic substrate and a deterioration of hydrophilicity for a superhydrophilic substrate. As a result, with increasing temperature, the influence of the droplet geometry determined by surface wettability on the droplet evaporation rate for these substrates sharply decreases. Advancing and receding dynamic contact angles, as well as contact angle hysteresis were obtained on all studied substrates. It is generally accepted that a hydrophobic surface exhibits less contact angle hysteresis than a hydrophilic one. However, Cu-SiС composite substrate with a textured hydrophobic surface exhibited the opposite behavior. The contact angle hysteresis on the hydrophobic textured surface was found to be four times higher than that on the hydrophilic polished one. A mechanism was proposed that explains the high contact angle hysteresis and four hysteresis time modes. The minimum hysteresis value corresponded to the superhydrophobic AlMg3 substrate. Anti-corrosion properties were studied for all substrates under consideration. The minimum corrosion current corresponded to a copper substrate with a graphene coating, as well as a superhydrophobic AlMg3 substrate. For a given substrate, there are two corrosion modes with a three-fold difference in the corrosion current. In addition, the wettability behavior of different surfaces was examined using molecular dynamics simulations. The simulation results were found to be consistent with the experimental data.

Analysis of the mechanical, thermal and frictional behavior of Cu-sepiolite composite materials

To enhance the wear resistance of copper, sepiolite was used as a reinforcing element to explore the interface bonding strength between both. A comprehensive analysis was conducted from mechanical, thermal, and frictional perspectives to elucidate the role of sepiolite in copper. The results reveal that the interface between both remains undamaged under the applied loads of 0.4 N, with only minimal plastic deformation. However, excessive interface formation could compromise the continuity of the copper, resulting in reduced structural densification and impeded thermal conductivity. Moreover, sepiolite exhibited a particle strengthening effect, improving the mechanical strength. In which, H2 (20% sepiolite) exhibited the most significant characteristics, featuring a dense structure, small pores, and high shear strength and thermal conductivity, particularly excelling in Brinell Hardness (81.9HB). However, the frictional performance varied, gradually strengthening with the increasing amount of sepiolite. Notably, sepiolite acts as micro-protrusions to counteract friction forces. Partially fragmented sepiolite adheres to the friction surface, forming a mixed layer that facilitates the abundant generation of Cu2O. Besides, the CaCO3 in sepiolite undergoes thermal decomposition, resulting in the formation of CaO, both of which also function as micro-protrusions.

Prediction of thermal behavior of Earthen-Straw composite material with 3D numerical modeling of a random geometry without overlapping

Nowadays, stabilizing raw soil with straw fibers represents a sustainable eco-building practice. Moreover, the rebirth of the earth’s construction is primarily driven by the material’s thermal properties. In the present work, a 3D study of the earthen-straw composite material’s thermal behavior has been carried out to promote its use in construction and ensure satisfactory living conditions for the building. To consider the most possible influencing factors, the effect of fibers concentration on thermal conductivity was investigated for the straw contents of 5%, 10% and 15% by volume of earthen. Thus, a 3D model with a random distribution of straw fibers considered as cylinders without overlapping was designed under Catia V5. The distribution uses datasets from a hybrid algorithm developed for this purpose, which is then imported to Ansys Software to carry out the simulation allowing the computation of the thermal conductivity of the homogeneous material. It can be concluded that the proposed hybrid algorithm was efficient since the 3D numerical results based on the geometry generated by the algorithm’s output were satisfactory in comparison with those deducted from the 2D study and the existing theoretical models. On the other hand, adding straw fibers in the raw earth matrix with thermal conductivity equal to 0.75 W/(m.K) has enhanced its thermal insulation. Indeed, for 15% of straw fiber’s contents, we have found 0.633 W/(m.K) for the thermal conductivity of the earthen-straw composite material, which is equivalent to a decrease of 15.6% in this intrinsic parameter.