Composite Laminates Research Articles

Recent Advances in Healable Carbon-Fiber-Reinforced Epoxy Resin Composite Laminate: Preparation and Properties

Recent Advances in Healable Carbon-Fiber-Reinforced Epoxy Resin Composite Laminate: Preparation and Properties

Failure analysis of angle‐ply thin woven GFRP composites under low‐velocity impact and low‐temperature

AbstractA comprehensive experimental and analytical study was conducted on quasi‐isotropic woven glass fiber‐reinforced polymer composites with a stacking sequence of [0°/±45°/90°]s, under low‐velocity impact at a low temperature of −50 °C. The results were compared to those at room temperature. The performance of the composite laminate was evaluated using 20 measured parameters for each impact test. Although these parameters may have been identified across dispersed numerous studies on different FRP composite materials, varying temperatures, and different impact levels, often result in scattered findings that complicate establishing accurate conclusions. This highlights the importance of the current study, which deals with 20 impact performance parameters within a single article for a comprehensive analysis. Among the important results of this study is the higher impact energy absorption efficiency of up to 76% at −50 °C, which demonstrates the strong performance of the composite laminates under low‐temperature and impact loads. The increase in energy absorption with impact energy correlates with an increase in impact bending stiffness, delamination threshold force, peak force, and rebound energy. The impact bending stiffness increases linearly with impact energy as the higher strain rate restricts polymer chain mobility, resulting in a stiffer and more brittle response. The predicted delamination threshold force, aided by classical laminate theory, significantly contributes to understanding various damage mechanisms at different impact levels. The prediction of the peak force using the effective peak contact force model and the multivariate regression model revealed strong agreement with the measured values, achieving a coefficient of determination above 0.99.Highlights LVI behavior of woven GFRP composites at low temperatures is vital for aerospace. New insights into damage mechanisms and failure prediction. Correlations of the damage assessment parameters with 20‐impact parameters. Perimeter damage length is a new damage assessment parameter. Explored energies of threshold delamination, damage propagation, and rebound.

Influence of epoxy methyl ricinoleate on mechanical, visco‐elastic, and low‐velocity impact properties of flax fiber reinforced epoxy composite

AbstractDue to the decline in petroleum‐derived resources and growing environmental awareness, scientists are seeking bio‐based alternatives for synthetic fibers and resins in composites. This study examines the effect of partially substituting epoxy components with castor oil‐based bio‐resins. The goal is to develop environmentally sustainable materials while maintaining performance. Epoxy methyl ricinoleate (EMR) was synthesized and assessed as a supplementary component in an epoxy copolymer cured with Triethylenetetramine. Flax fabric was used as reinforcement in epoxy and epoxy–EMR copolymer matrices to create eco‐friendly bio‐composites. The epoxy matrix was modified with 10%, 20%, and 30% EMR and combined with bidirectional flax fabric to balance toughness and stiffness. Tensile strength increased by 6.5% in EPEMR/20‐C. Impact strength improved by 19% in EPEMR/30‐C compared to the neat epoxy composite. EMR incorporation, especially up to 20%, enhanced ILSS by about 13%. Fatigue performance improved by 43% due to increased matrix toughness and better interfacial bonding. Low‐velocity impact tests were performed at 10 and 20 J to study perforation and non‐perforation scenarios. The composite with 20% EMR showed the highest impact resistance. This highlights its potential for structural components with reduced weight and improved interfacial bonding. EMR‐modified bio‐composites were eco‐friendly and exhibited enhanced mechanical properties. These findings suggest their suitability for structural and automotive applications.Highlights The effects of EMR bio‐resin on epoxy composites are analyzed. High bio‐content composites, comprising approximately 50 wt%, are developed. EMR improved bio‐composites' fatigue by 43% via tougher matrix and bonding. Optimal EMR addition enhances composite laminates' impact resistance in LVI tests. Toughness and bio‐content were enhanced by adding EMR.

Closed-Form Formulas for the Optimum Design of Composite Laminates Under In-Plane Loading

Closed-Form Formulas for the Optimum Design of Composite Laminates Under In-Plane Loading

Enhancing the temperature resistance of hybrid basalt/glass epoxy laminates

AbstractThis study examines the tensile properties of hybrid basalt/glass epoxy laminates, specifically focusing on the impact of fiber arrangement on these properties at high temperatures. The composite laminates were manufactured utilizing the hot compression molding technique and underwent tensile testing at 25–400°C. Thermogravimetric analysis (TGA) and chemical composition analysis were used to evaluate the thermal and chemical features of basalt fiber (BF) and glass fiber (GF). The tensile strength and elastic modulus of G₄B₄G₄, B₂G₈B₂, B₆G₆, B₄G₄B₄, G₂B₈G₂, and B₁₂ demonstrated slight enhancements or remained relatively stable when the temperatures increased from ambient temperature (25°C) to 100°C; however, the laminate G₁₂ exhibited the weakest performance. It was also noted that the laminates with a larger percentage of basalt fiber (BF) showed superior performance compared to those with a larger percentage of glass fiber (GF). This was especially evident when the basalt fiber (BF) was used in the outer layer, leading to enhanced performance from ambient temperature up to 400°C. Nevertheless, all the laminates’ tensile strength and elastic modulus significantly decreased under temperatures ranging from 200 to 400°C.Highlights Higher ratios of BF enable hybrid laminates to show more thermal stability. At elevated temperatures, BF laminates perform better than GF Laminates maintain tensile strength up to 100°C but decrease at 200°C. BF in outer layers increases thermal resistance.

A meshless method for thermal vibration analysis of curved-edge trapezoidal plates made of laminated materials

Abstract This paper reports a meshless method for stochastic vibration analysis of trapezoidal composite laminates with curvilinear bound. The basis functions used in this meshless method are Chebyshev polynomials, which are adapted to the defining domain of the Chebyshev polynomials by transforming the curved-edge plate into a square plate using a coordinate mapping technique. The developed vibration analysis model combines the first-order shear deformation theory (FSDT) and thermos-elasticity theory using the Hamiltonian variational principle. The displacement tolerance function of the square plate is approximated by a two-dimensional meshless Chebyshev-radial basis point interpolation method. Gaussian Lobato sampling points are used to discretize the square domain. The correctness and efficiency of the model is verified by comparison with finite element results and published literature. The effects of temperature, geometry, and stochastic loading on the vibration characteristics of curved edge trapezoidal plates are also carried out. The results show that the existing Chebyshev-radial basis point interpolation method can accurately and efficiently calculate the vibration characteristics of curved-edge trapezoidal plates under different boundary conditions.

Compression and bending properties of regularly arrayed short fiber reinforced composite laminates: Experimental and numerical analysis

AbstractUnidirectional arrayed chopped strands (UACS) are made by introducing regularly distributed slits into continuous fiber prepregs, which show better flowability and formability while maintaining high strength and modulus. In this research, the quasi‐static compression and three‐point bending tests were carried out on quasi‐isotropic continuous fiber laminates and UACS laminates. The results illustrate that the compressive modulus and strength of UACS laminates are 53.38 GPa and 489.58 MPa, respectively, which maintain relatively high mechanical properties. The bending strength of UACS laminates decreased by 7.3%, but its bending modulus remained stable. Additionally, UACS laminates exhibit better resistance to shear and delamination damage while retaining good bending properties. To further explore the mechanical behavior of UACS laminates, finite element models were established to numerically analyze the mechanical properties and damage mechanism of laminates under compressive and bending loads. The present model could accurately simulate the mechanical properties of UACS laminates, and the errors of the numerical analysis results of the compression modulus and strength are 6.03% and 4.05%, respectively. From the analysis of the damage mechanism, the regularly arrayed slits ensure the UACS laminates have lower energy release rates during damage, which enables stable damage evolution and plays a positive effect in reducing the damage area and inhibiting delamination.Highlights The response of UACS under compression and bending loads was studied. The effect of slits on the damage of UACS laminate was revealed. The bending damage distribution of UACS laminates was studied. The difference between conventional CFRP and UACS is analyzed.

Monte Carlo Micro-Stress Field Simulations in Flax/E-Glass Composite Laminae with Non-Circular Flax Fibres

This study explores the mechanical behaviour of intra-laminar hybrid flax/E-glass composites, focusing on the role of micro-scale irregularities in flax fibres. By employing computational micromechanics and Monte Carlo simulations, it analyses the influence of flax fibre geometry and elastic properties on the performance of hybrid and non-hybrid composites. A Non-Circular Fibre Distribution (NCFD) algorithm is introduced to generate microstructures with randomly distributed non-circular flax and circular E-glass fibres, which are then modelled using a 3D representative volume element (RVE) model developed in Python 2.7 and implemented with Abaqus/Standard. The RVE dimensions were specified as ten times the mean characteristic length of flax fibres (580 μm) for the width and length, while the thickness was defined as one-tenth the radius of the E-glass fibre. Results show that Monte Carlo simulations accurately estimate the effect of fibre variabilities on homogenised elastic constants when compared to measured values and Halpin-Tsai predictions, and they effectively evaluate the fibre/matrix interfacial stresses and von Mises matrix stresses. While these variabilities minimally affect the homogenised properties, they increase the presence of highly stressed regions, especially at the interface and matrix of flax/epoxy composites. Additionally, intra-laminar hybridisation further increases local stress in these critical areas. These findings improve our understanding of the relationship between the natural fibre shape and mechanical performance in flax/E-glass composites, providing valuable insights for designing and optimising advanced composite materials to avoid or delay damage, such as matrix cracking and splitting, under higher applied loads.

Exploring the role of shape memory alloys in advanced composite sandwich panels and laminates

Exploring the role of shape memory alloys in advanced composite sandwich panels and laminates

Simplified model for the tool-part interaction in spring-in of L-shape composite laminates

Simplified model for the tool-part interaction in spring-in of L-shape composite laminates

Forming limits of highly aligned discontinuous fiber composite laminates

Forming limits of highly aligned discontinuous fiber composite laminates

The effects of high strain-rate and temperature on tensile properties of UHMWPE composite laminates

The effects of high strain-rate and temperature on tensile properties of UHMWPE composite laminates

Enhanced surface adhesion and LWIR paint effect on the low vacuum radio-frequency argon plasma (LVRFAP) treated composite laminates for aerospace applications

Enhanced surface adhesion and LWIR paint effect on the low vacuum radio-frequency argon plasma (LVRFAP) treated composite laminates for aerospace applications

Uncertainty quantification of residual strength post lightning strike: A coupled stochastic thermal–electrical–mechanical simulation framework for composite laminates

Uncertainty quantification of residual strength post lightning strike: A coupled stochastic thermal–electrical–mechanical simulation framework for composite laminates

Thermal-oxidative aging mechanism of carbon fiber reinforced self-catalytic phthalonitrile resin matrix composite laminates at 450 ℃ ∼ 500 ℃

Thermal-oxidative aging mechanism of carbon fiber reinforced self-catalytic phthalonitrile resin matrix composite laminates at 450 ℃ ∼ 500 ℃

High-velocity impact behavior of scarf-repaired composite laminates

High-velocity impact behavior of scarf-repaired composite laminates

Mechanical and statistical analysis of hand-woven jute fibre composite laminates with bio-based and synthetic matrices

Mechanical and statistical analysis of hand-woven jute fibre composite laminates with bio-based and synthetic matrices

Examination and clarification of R ratio in fatigue delamination growth analysis of composite laminates with fiber bridging

Examination and clarification of R ratio in fatigue delamination growth analysis of composite laminates with fiber bridging

Advanced Meta-Modeling framework combining Machine Learning and Model Order Reduction towards real-time virtual testing of woven composite laminates in nonlinear regime

Advanced Meta-Modeling framework combining Machine Learning and Model Order Reduction towards real-time virtual testing of woven composite laminates in nonlinear regime

Synchronous Application of DIC and DVC techniques for the Global-Local Characterization of Carbon Fiber-Reinforced Composite Laminates

Synchronous Application of DIC and DVC techniques for the Global-Local Characterization of Carbon Fiber-Reinforced Composite Laminates