scholarly journals Experimental Study on Compression Failure of Composite Laminates with Prefabricated Surface Cracks

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3616
Author(s):  
Wei Sun ◽  
Tian Ouyang ◽  
Zengshan Li ◽  
Yan Li
Keyword(s):  
Composite Laminates ◽  
Failure Modes ◽  
Leading Edge ◽  
Test Method ◽  
Surface Cracks ◽  
Test Fixture ◽  
Compression Failure ◽  
Isotropic Composite ◽  
Crack Tips ◽  
Complex Crack

A new compression test fixture was designed in the present work to study the damage tolerance of composite laminates with surface cracks or notches. The compression failure behaviors of CCF300/5228A quasi-isotropic composite laminates with prefabricated surface cracks were studied experimentally. Through the size design of the test fixture and specimens and an application of a simple test method, the complex crack growth process was captured. The experimental results showed that the compression failure modes were mainly affected by crack angles and depths, and there were two typical failure modes, which were local intra- and inter-laminar damage propagating from the crack tips and delamination growth induced from the crack leading edge. This study verified the validity of the test fixture and test method, and revealed the compression failure mechanisms of composite laminates with surface cracks.

Experimental Study on Interlaminar Shear Properties of T300/BMI Composite Laminates

2013 ◽  
Vol 718-720 ◽  
pp. 157-161
Author(s):  
Zong Hong Xie ◽  
Hai Han Liu ◽  
Jian Zhao ◽  
Jun Feng Sun ◽  
Fei Peng ◽  
...  
Keyword(s):  
Composite Laminates ◽  
Shear Test ◽  
Failure Modes ◽  
Shear Failure ◽  
Test Method ◽  
Test Results ◽  
Shear Properties ◽  
Test Fixture ◽  
Iosipescu Shear Test ◽  
Interlaminar Shear

A modified test fixture to measure the shear properties of composite laminates was designed and manufactured based upon Iosipescu shear test method. Tests on interlaminar shear propertis of T300/BMI composite laminates were conducted according to ASTM D 5379 test standard. Interlaminar shear stress/strain curves and shear failure modes were obtained. The test results showed that the modified shear test fixture and test method were effective in measuring the shear properties of composite laminates.

scholarly journals Evaluation of Energy Absorption Capabilities of Polyethylene Foam under Impact Deformation

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3613
Author(s):  
Baohui Yang ◽  
Yangjie Zuo ◽  
Zhengping Chang
Keyword(s):  
Energy Absorption ◽  
Failure Modes ◽  
High Strain ◽  
Early Stage ◽  
High Energy ◽  
Test Method ◽  
Test Theory ◽  
Strain Rates ◽  
Impact Properties ◽  
The Impact

Foams are widely used in protective applications requiring high energy absorption under impact, and evaluating impact properties of foams is vital. Therefore, a novel test method based on a shock tube was developed to investigate the impact properties of closed-cell polyethylene (PE) foams at strain rates over 6000 s−1, and the test theory is presented. Based on the test method, the failure progress and final failure modes of PE foams are discussed. Moreover, energy absorption capabilities of PE foams were assessed under both quasi-static and high strain rate loading conditions. The results showed that the foam exhibited a nonuniform deformation along the specimen length under high strain rates. The energy absorption rate of PE foam increased with the increasing of strain rates. The specimen energy absorption varied linearly in the early stage and then increased rapidly, corresponding to a uniform compression process. However, in the shock wave deformation process, the energy absorption capacity of the foam maintained a good stability and exhibited the best energy absorption state when the speed was higher than 26 m/s. This stable energy absorption state disappeared until the speed was lower than 1.3 m/s. The loading speed exhibited an obvious influence on energy density.

Effect of Transverse Moduli on Through-Thickness Hygrothermal Expansion Coefficients of Composite Laminates

2001 ◽  
Vol 68 (6) ◽  
pp. 878-879 ◽  
Author(s):  
H.-L. Yeh ◽  
H.-Y. Yeh
Keyword(s):  
Composite Laminates ◽  
Stress Condition ◽  
Physical Phenomenon ◽  
Point Of View ◽  
Plane Stress Condition ◽  
Geometrical Symmetry ◽  
Thermal Expansion Coefficients ◽  
Isotropic Composite ◽  
Practical Analysis ◽  
Expansion Coefficients

In practical analysis, under a plane stress condition, a unidirectional lamina can be assumed with E2=E3 from geometrical symmetry consideration. However, from an academic point of view, it is interesting to study the case of a lamina with E2≠E3. In this paper the preliminary results of the physical phenomenon about the effect of different transverse moduli E2 and E3 on the through-thickness thermal expansion coefficients αz of quasi-isotropic composite laminates is presented.

Flexural Response of Inorganic Hybrid Composites With E-Glass and Carbon Fibers

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
James W. Giancaspro ◽  
Christos G. Papakonstantinou ◽  
P. N. Balaguru
Keyword(s):  
Carbon Fibers ◽  
Hybrid Composite ◽  
Composite Laminates ◽  
Hybrid Composites ◽  
Glass Fibers ◽  
Composite Plates ◽  
Carbon Composite ◽  
Primary Objective ◽  
Flexural Capacity ◽  
Compression Failure

By far, carbon and glass fibers are the most popular fiber reinforcements for composites. Traditional carbon composites are relatively expensive since the manufacturing process requires significant heat and pressure, while the carbon fibers themselves are inherently expensive to produce. In addition, they are often flammable and their use is restricted when fire is a critical design parameter. Glass fabrics are approximately one order of magnitude less expensive than similar carbon fabrics. However, they lack the stiffness and the durability needed for many high performance applications. By combining these two types of fibers, hybrid composites can be fabricated that are strong, yet relatively inexpensive to produce. The primary objective of this study was to experimentally investigate the effects of bonding high strength carbon fibers to E-glass composite cores using a high temperature, inorganic matrix known as geopolymer. Carbon fibers were bonded to E-glass cores (i) on only the tension face, (ii) on both the tension and compression faces, or (iii) dispersed throughout the core in alternating layers to obtain a strong, yet economical, hybrid composite laminate. For each response measured (flexural capacity, stiffness, and ductility), at least one hybrid configuration displayed mechanical properties comparable to all carbon composite laminates. The results indicate that hybrid composite plates manufactured using 3k unidirectional carbon tape exhibit increases in flexural capacity of approximately 700% over those manufactured using E-glass fibers alone. In general, as the relative amount of carbon fibers increased, the likelihood of precipitating a compression failure also increased. For 92% of the specimens tested, the threshold for obtaining a compression failure was utilizing 30% carbon fibers. The results presented herein can dictate future studies to optimize hybrid performance and to achieve economical configurations for a given set of design requirements.

Numerical and experimental evaluation of mechanical performance of the multifunctional energy storage composites

2021 ◽  
pp. 002199832110495
Author(s):  
Yinan Wang ◽  
Fu-Kuo Chang
Keyword(s):  
Energy Storage ◽  
Carbon Fiber ◽  
Composite Laminates ◽  
Failure Modes ◽  
Mechanical Performance ◽  
Fiber Composite ◽  
Mechanical Damage ◽  
Experimental Tests ◽  
Structural Element ◽  
Carbon Fiber Composite

This work presents numerical simulation methods to model the mechanical behavior of the multifunctional energy storage composites (MESCs), which consist of a stack of multiple thin battery layers reinforced with through-the-hole polymer rivets and embedded inside carbon fiber composite laminates. MESC has been demonstrated through earlier experiments on its exceptional behavior as a structural element as well as a battery. However, the inherent complex infrastructure of the MESC design has created significant challenges in simulation and modeling. A novel homogenization technique was adopted to characterize the multi-layer properties of battery material using physics-based constitutive equations combined with nonlinear deformation theories to handle the interface between the battery layers. Second, mechanical damage and failure modes among battery materials, polymer reinforcements, and carbon fiber-polymer interfaces were characterized through appropriate models and experiments. The model of MESCs has been implemented in a commercial finite element code in ABAQUS. A comparison of structural response and failure modes from numerical simulations and experimental tests are presented. The results of the study showed that the predictions of elastic and damage responses of MESCs at various loading conditions agreed well with the experimental data. © 2021

Numerical modeling of failure modes in bolted composite laminates

2015 ◽  
Author(s):  
Francesca Nerilli ◽  
Luca Tarquini ◽  
Michele Marino ◽  
Giuseppe Vairo
Keyword(s):  
Numerical Modeling ◽  
Composite Laminates ◽  
Failure Modes

Experimental investigation and modeling of dynamic thermomechanical behavior of 4-harness satin weave carbon/epoxy composites

2017 ◽  
Vol 31 (9) ◽  
pp. 1181-1203 ◽  
Author(s):  
Xueyao Hu ◽  
Hui Guo ◽  
Weiguo Guo ◽  
Feng Xu ◽  
Longyang Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Strain Rate ◽  
Composite Laminates ◽  
Failure Modes ◽  
Shear Failure ◽  
Experimental Studies ◽  
Temperature Shift ◽  
Thermomechanical Coupling ◽  
Longitudinal Splitting ◽  
Wide Range

Theoretical and experimental studies on the compressive mechanical behavior of 4-harness satin weave carbon/epoxy composite laminates under in-plane loading are conducted over the temperature range of 298–473 K and the strain rate range of 0.001–1700/s in this article. The stress–strain curves of 4-harness satin weave composites are obtained at different strain rates and temperatures, and key mechanical properties of the material are determined. The deformation mechanism and failure morphology of the samples are observed and analyzed by scanning electron microscope (SEM) micrographs. The results show that the uniaxial compressive mechanical properties of 4-harness satin weave composites are strongly dependent on the temperature but are weakly sensitive to strain rate. The peak stress and elastic modulus of the material have the trend of decrease with the increasing of temperature, and the decreasing trend can be expressed as the functional relationship of temperature shift factor. In addition, SEM observations show that the quasi-static failure mode of 4-harness satin weave composites is shear failure along the diagonal lines of the specimens, while the dynamic failure modes of the material are multiple delaminations and longitudinal splitting, and with the increasing of temperature, its longitudinal splitting is more serious, but the delamination is relatively reduced. A constitutive model with thermomechanical coupling effects is proposed based on the experimental results and the increment theory of elastic–plastic mechanics. The experimental verification and numerical analysis show that the model is shown to be able to predict the finite deformation behavior of 4-harness satin weave composites over a wide range of temperatures.

Sign in / Sign up

Export Citation Format

Share Document