Impact Behavior of Cracked Plate Repaired with Composite and FML Patches

2008 ◽  
Vol 47-50 ◽  
pp. 612-616 ◽  
Author(s):  
Mehdi Sadeghinia ◽  
Seyyed Mohammad Reza Khalili ◽  
R. Ghadjar
Keyword(s):  
Crack Length ◽  
Charpy Impact ◽  
Thin Layers ◽  
Impact Behavior ◽  
Single Edge ◽  
Absorbed Energy ◽  
Cracked Plate ◽  
Cracked Plates ◽  
Single Side ◽  
The Impact

In this paper, the impact behavior of repaired cracked plates was investigated experimentally. single edge cracked aluminum plate having crack length to width ratios of 0.1, 0.3 and 0.5 was repaired with four different patch configurations namely: 3 layer GRP, 5 layer GRP patch, 2/1 FML patch and 3/2 FML patches tested in Charpy impact and the energy absorbed by specimens were compared together and compared with the unrepaired cracked plate. FML patches were made of thin layers of glass/epoxy composites of 0.2 mm thickness with phosphor bronze sheets of 0.2 mm thickness. The patching was single side. The composite and FML patching was more effective in repairing the specimens with greater crack length. Placing 3 GRP and 5 GRP patches increased the absorbed energy by only 3 to 4 joules respectively as compared to unrepaired plate. The use of 2/1 and 3/2 FML patches could increase the absorbed energy two to four times depend on crack length.

Experimental investigation on tensile and Charpy impact behavior of Kevlar/S-glass/epoxy hybrid composite laminates

2017 ◽  
Vol 37 (2) ◽  
pp. 177-184 ◽  
Author(s):  
Ahmet Erkliğ ◽  
Mehmet Bulut
Keyword(s):  
Impact Strength ◽  
Hybrid Composite ◽  
Composite Laminates ◽  
Glass Fibers ◽  
Impact Resistance ◽  
Charpy Impact ◽  
Side Impact ◽  
Impact Behavior ◽  
Absorbed Energy ◽  
Mixing Ratios

Abstract The aim of this study is to evaluate the effect of hybridizing Kevlar and glass fibers on the tensile and Charpy impact properties of their composites. Produced hybrid samples were designed as unbalanced and asymmetric structures in terms of different mixing ratios between woven Kevlar and S-glass fibers, and their tensile properties were determined using ASTM standards. A series of Charpy impact tests were performed to evaluate the amount of impact strength and absorbed energy by impacting each side of the hybrid composite samples. When the hybrid samples were impacted on the surface of the Kevlar side, they exhibited higher impact resistance compared with glass side impact. The resulting degree of hybridization effects showed that addition of Kevlar layers instead of glass layers contributed a significant increase in impact strength and absorbed energy of the overall composite laminate.

Charpy Impact Response of the Cracked Aluminum Plates Repaired with FML Patches using the Response Surface Methodology

2016 ◽  
Vol 66 (5) ◽  
pp. 536
Author(s):  
Faramarz Ashenai Ghasemi ◽  
Lotfali Mozaffari Vanani ◽  
Ali Pourkamali Anaraki ◽  
Sadigh Raissi
Keyword(s):  
Response Surface Methodology ◽  
Crack Length ◽  
Response Surface ◽  
Energy Absorption ◽  
Charpy Impact ◽  
Experimental Results ◽  
Impact Response ◽  
Crack Angle ◽  
Aluminum Plates ◽  
The Impact

<p style="margin: 0cm 0cm 10pt; text-align: justify; line-height: normal;">Here, the effect of fiber metal laminate (FMLs) patches was studied for repairing of single-sided cracked aluminum plates experimentally to see their response to Charpy impact tests. The main desired parameters were composite patch lay-up, crack length, and crack angle each one in three levels. All experimental attempts generated and followed based on the design of experiments method by using of response surface methodology. The predicted energy absorption values obtained from the model were in good agreement with the experimental results. No matter the specimens were repaired or not, as the crack length was increased the energy absorption of the structure was decreased. The experimental results also showed that for lengthen cracks, increasing of the crack angle had more effect on energy absorption. Also it was observed that the patch lay-up effective on the impact response of the specimens. The more the metal layer was departed from the aluminum plate and the FML patches interfacial surface, the less energy was absorbed in the structure.</p>

Investigation of Energy Absorbed from an Instrumented Charpy Impact on Automotive Specimens

2012 ◽  
Vol 165 ◽  
pp. 182-186 ◽  
Author(s):  
M. B. Ali ◽  
S. Abdullah ◽  
Mohd Zaki Nuawi ◽  
Ahmad Kamal Ariffin
Keyword(s):  
Strain Energy ◽  
Charpy Impact ◽  
Strain Gauges ◽  
Absorbed Energy ◽  
Signal Pattern ◽  
Signal Collection ◽  
Spectrum Density ◽  
The Time Domain ◽  
The Impact ◽  
Strain Signal

This paper presents the analysis of energy absorbed that produced from an instrumented charpy impact in order to evaluate the toughness of materials. Alloy rims made from aluminium 6061-T6 are easily damage, fracture and can even destroy after impact loading compared to the steel rim. For this reason, an idea was initiated to determine the strain signal pattern and strain energy for evaluting the toughness of materials. Strain gauges were experimentally connected to the data acquisition system and it was then attached to the charpy striker for the impact signal collection. Specimens of aluminium alloy of 6061-T6 and carbon steel 1050 were used and its were designed according to the ASTM E23 standard. In this work, the signal was converted from the time domain to the frequency domain using the power spectrum density (PSD) method and the area under its graph was then used to calculate strain energy. The comparison between absorbed energy and strain energy was performed based on different materials and thicknesses. It was found the effect of the strain signal pattern with different materials and thicknesses to be influnced the strain energy.

Experimental study of the impact behavior of laminated composites stricken by sharp impactors

2012 ◽  
Vol 19 (3) ◽  
pp. 307-313 ◽  
Author(s):  
Mesut Uyaner ◽  
Memduh Kara
Keyword(s):  
Contact Force ◽  
Impact Behavior ◽  
Test Machine ◽  
Absorbed Energy ◽  
Nominal Thickness ◽  
Weight Test ◽  
Force Time ◽  
Drop Weight Test ◽  
The Impact ◽  
Composite Samples

AbstractIn this study, the influence of the impactor shape on the dynamic response of E-glass/epoxy laminates was investigated. Composite samples were impacted using steel 90° and 120° conical, 24 mm and 12 mm in diameter hemispherical, pyramidal impactors via a specially developed drop weight test machine. The impact tests were performed at impactor mass (20 kg) for impact velocity (2.5 m/s). Plate specimens consisting of 18 plies for tests (180×50 mm) with a nominal thickness (7 mm) were used. Contact force-time and contact force-deflection data obtained from the experiments were interpreted. It was found that the contact force was smaller in the 90° conical impactor while it was bigger in the 24 mm hemispherical one. Absorbed energies were also investigated. The absorbed energy obtained for pyramidal impactor was greater than that of the others. Furthermore, overall damage areas caused by the impactor were evaluated.

The Charpy Impact Behavior of Fe3Al and Fe3Al-20 at % Mn Alloys

1996 ◽  
Vol 460 ◽  
Author(s):  
J. N. Liu ◽  
W. Yan ◽  
J. L. Ma ◽  
K. H. Wu
Keyword(s):  
Impact Energy ◽  
Charpy Impact ◽  
Testing Temperature ◽  
Impact Behavior ◽  
Al Alloy ◽  
Impact Fracture Behavior ◽  
Series Of Experiments ◽  
Growth Energy ◽  
The Impact ◽  
Total Impact

ABSTRACTA series of experiments were conducted to investigate the impact fracture behavior of Fe3Al and Fe3Al-20 Mn alloys. The results of this study indicated that: (i) The addition of Mn introduces an ordered Ll2-type phase in the Fe3Al-based alloys. On the other hand, the addition of Mn decreases the order parameter of the DO3 a phase, (ii) The total- impact energy of an Fe3Al alloy increases with the temperature at the low-temperature range (<600°C), then drops around 700°C, and finally increases again as the temperature further elevates, (iii) The trend of the variation of the impact energy of Fe3Al-20 at % Mn alloy with temperature is the same as that of the Fe3Al alloy, (iv) And the addition of Mn significantly improves the impact energy of the Fe3Al-based alloy, and changes the variation of the crack-growth energy with the testing temperature when the temperature is above 700°C.

An Experimental Study on J(CTOD)-R Curves of Single Edge Tension Specimens for X80 Steel

2012 ◽  
Author(s):  
Enyang Wang ◽  
Wenxing Zhou ◽  
Guowu Shen ◽  
Daming Duan
Keyword(s):  
Crack Length ◽  
Crack Tip ◽  
Initial Crack ◽  
Single Edge ◽  
X80 Steel ◽  
Toughness Testing ◽  
Unloading Compliance ◽  
Crack Tip Constraint ◽  
The Impact ◽  
Edge Tension

Fracture toughness testing of SE(T) and SE(B) specimens is carried out to experimentally develop J(CTOD)-R curves for the X80 steel based on the unloading compliance method. Six clamped (two shallow-cracked side-grooved, two deep-cracked side-grooved, and two deep-cracked plain-sided) SE(T) and two shallow-cracked side-grooved SE(B) specimens are tested. The impact of crack length on the J(CTOD)-R curves of the SE(T) specimens is investigated. The J(CTOD)-R curves of the shallow-cracked SE(T) specimens are significantly higher than those of the deep-cracked SE(T) specimens once the crack extension exceeds 0.5 mm. A comparison of the J(CTOD)-R curves associated with the SE(B) and SE(T) specimens suggests that the crack tip constraint for the SE(T) specimens is lower than that of the SE(B) specimens with the same nominal initial crack length, and that shallow-cracked SE(T) specimens have less constraint at the crack tip than deep-cracked SE(T) specimens.

scholarly journals Charpy Impact Properties of Hydrogen-Exposed 316L Stainless Steel at Ambient and Cryogenic Temperatures

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 625 ◽  
Author(s):  
Le Thanh Hung Nguyen ◽  
Jae-Sik Hwang ◽  
Myung-Sung Kim ◽  
Jeong-Hyeon Kim ◽  
Seul-Kee Kim ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Stainless Steel ◽  
Low Temperatures ◽  
316L Stainless Steel ◽  
Charpy Impact ◽  
Cryogenic Temperatures ◽  
Absorbed Energy ◽  
Impact Properties ◽  
Charging Time ◽  
The Impact

316L stainless steel is a promising material candidate for a hydrogen containment system. However, when in contact with hydrogen, the material could be degraded by hydrogen embrittlement (HE). Moreover, the mechanism and the effect of HE on 316L stainless steel have not been clearly studied. This study investigated the effect of hydrogen exposure on the impact toughness of 316L stainless steel to understand the relation between hydrogen charging time and fracture toughness at ambient and cryogenic temperatures. In this study, 316L stainless steel specimens were exposed to hydrogen in different durations. Charpy V-notch (CVN) impact tests were conducted at ambient and low temperatures to study the effect of HE on the impact properties and fracture toughness of 316L stainless steel under the tested temperatures. Hydrogen analysis and scanning electron microscopy (SEM) were conducted to find the effect of charging time on the hydrogen concentration and surface morphology, respectively. The result indicated that exposure to hydrogen decreased the absorbed energy and ductility of 316L stainless steel at all tested temperatures but not much difference was found among the pre-charging times. Another academic insight is that low temperatures diminished the absorbed energy by lowering the ductility of 316L stainless steel.

scholarly journals RESISTÊNCIA AO IMPACTO DE COMPÓSITOS DE FIBRA DE CARBONO E RESINA EPÓXI EM COMPARAÇÃO AO AÇO SAE 1010

2018 ◽  
Vol 4 (1) ◽  
pp. 0127-0142
Author(s):  
Giovanni de Carvalho Mazarim ◽  
Gigliola Salerno
Keyword(s):  
Composite Material ◽  
Carbon Fiber ◽  
Fiber Orientation ◽  
Charpy Impact ◽  
Impact Behavior ◽  
Low Density ◽  
Resin Composites ◽  
Composites Materials ◽  
Epoxy Resin Composites ◽  
The Impact

A indústria automobilística visa desenvolver veículos com melhor desempenho e os materiais compósitos atingem este quesito pois apresentam alta resistência mecânica e baixa densidade. Visando aplicar tal material para a confecção da proteção das polias CVT de um carro BAJA, este trabalho tem como objetivo estudar o comportamento ao impacto dos materiais compósitos, variando a orientação das fibras, em comparação ao aço 1010. Foram conduzidos ensaios de impacto Charpy no material metálico e no compósito nas configurações unidirecionais (0° e 90°), 0°/90°, ±45° e 0°/90°/±45°. Os resultados obtidos mostraram influência dos defeitos gerados no processamento e a absorção de maiores valores de energia decorrente dos mecanismos de liberação de energia dos materiais compósitos. Adicionalmente, foi observado que a configuração ±45° apresentou um melhor desempenho, sendo a melhor opção.The industry is increasingly required to develop vehicles with better performance and composites materials are often the first option due their high mechanic resistance combined with low density. In order to apply this material on CVT protection of BAJA style car, this work main purpose was to study the impact behavior of the carbon fiber and epoxy resin composites, varying the fiber orientation, and compare to the SAE 1010 steel. For that reason, it were performed Charpy impact tests on the steel and on the unidirectional (0° and 90°), 0°/90°, ±45° and mixed (0°/90°±45°) configurations composite material. The results showed that defects inserted during the manufacturing process provided a huge influence on their energy absorbed. It was seen that higher energy absorbed occurred due damage mechanisms release energy. As a conclusion, the ±45° showed the best performance.

Impact response of E-glass/epoxy composite bi-directional corrugated core sandwich panels

2020 ◽  
pp. 096739112098275
Author(s):  
A Shahbazi ◽  
A Zeinedini
Keyword(s):  
Finite Element ◽  
Epoxy Composite ◽  
Impact Response ◽  
Impact Behavior ◽  
Absorbed Energy ◽  
Specific Energy Absorption ◽  
Additive Manufacturing Technology ◽  
The Core ◽  
Numerical Predictions ◽  
The Impact

In this paper, the impact response of bi-directional corrugated core sandwich structures was investigated. The core and skins were made of E-glass/epoxy laminated composites. Additive manufacturing technology was used to print the molds applied to fabricate the cores. The influence of different periods, i.e. T = 30, 37.5, 50 and 75 mm, of the double-cosine corrugated core on the impact response of the panels was evaluated. In addition, some other panels with regular corrugated cores were manufactured to evaluate the impact response of the bi-directional corrugated core structures. A finite element modeling was also carried out to analyze the impact behavior of the samples. The empirical measurements and the numerical predictions showed that the panels with the bi-directional corrugated core have a significant improvement in the absorbed energy under impact loading at each given period. It was also manifested that the panel consisting of the bi-directional corrugated core with T = 37.5 mm has the highest specific energy absorption.

scholarly journals ISSI 2020: Mechanism and Method of Testing Fracture Toughness and Impact Absorbed Energy By Spherical Indentation Tests

2021 ◽  
Author(s):  
Jianxun Li ◽  
Tairui Zhang ◽  
Shang Wang ◽  
Jirui Cheng ◽  
Weiqiang Wang
Keyword(s):  
Fracture Toughness ◽  
Charpy Impact ◽  
Damage Mechanism ◽  
Spherical Indentation ◽  
Mode I ◽  
Absorbed Energy ◽  
Mode I Fracture ◽  
Indentation Tests ◽  
Static Fracture ◽  
The Impact

Abstract Aimed at the problem that conventional approaches for mechanical property determination all need destructive sampling, which may be improper for in-service structures, the authors proposed a method to determine the quasi-static fracture toughness and impact absorbed energy from spherical indentation tests (SITs) in this study. The stress status and damage mechanism of SIT, Mode I fracture, Charpy impact tests, and related tests were first investigated through finite element (FE) calculations and scanning electron microscope (SEM) observations, respectively. It was found that the damage mechanism of SITs is different from Mode I fracture, while the Mode I fracture and Charpy impact test share the same damage mechanism. Taking the difference between SIT and Mode I fracture into consideration, the uniaxial tension and pure shear were introduced to correlate SIT with Mode I fracture. Based on which, the widely used critical indentation energy (CIE) model in fracture toughness determination from SITs was modified. The quasi-static fracture toughness determined from the modified CIE model was used in evaluating the impact absorbed energy by means of the dynamic fracture toughness and energy to crack initiation. Effectiveness of the new proposed method was verified through experiments on four kinds of steels, i.e. Q345R, SA508-3, 18MnMoNbR, and S30408.

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