Influence of Moisture Absorption on Impact Strength and Failure Behavior of Hybrid Jute-Carbon/ Epoxy Composite

2011 ◽  
Vol 264-265 ◽  
pp. 457-462 ◽  
Author(s):  
T.A. Lenda ◽  
S. Mridha
Keyword(s):  
Impact Strength ◽  
Moisture Content ◽  
Immersion Time ◽  
Moisture Absorption ◽  
Water Immersion ◽  
Fiber Content ◽  
Failure Behavior ◽  
Fiber Volume ◽  
Volume Fractions ◽  
Fiber Fractions

Hybrid jute-carbon/ epoxy composites, fabricated by hand lay-up method with fiber volume fractions of 0.47, 0.58 and 0.68 were used to investigate water absorption behavior as a function of immersion time and fiber content. The effect of moisture content on impact strength and failure modes was also studied. Results show that the moisture absorption increased with increasing the immersion time in water and it was more with higher fiber fraction specimens. Maximum moisture contents of 0.45%, 0.52% and 0.61% were recorded for the specimens containing fiber volume fractions of 0.47, 0.58 and 0.68, respectively. The impact strength reduced with increasing moisture absorption in all specimens containing different fiber fractions. Composites with higher fiber content gave reduced impact strength under all test conditions. Composites of different fiber fractions and of highest moisture content produced impact strengths about 20 to 28% less than those strengths obtained without water immersion. The 47 vol% fiber specimen was least affected by water immersion and impact strength reduction was only 17% after immersion till saturation. Failure occurred by mainly by delamination and it was evident in all fractured specimens. Results of the effect of impact energy on moisture content have been evaluated using ANOVA ANALYSIS and the results gave errors of 1%, 0.6 % and 0.8 % for 0.47, 0.58 and 0.68 fiber volume fraction specimens, respectively.

Effect of Moisture Absorption on the Bending Strength of CFRP

2012 ◽  
Vol 450-451 ◽  
pp. 482-485 ◽  
Author(s):  
A Ying Zhang ◽  
Di Hong Li ◽  
Dong Xing Zhang
Keyword(s):  
Moisture Content ◽  
Composite Laminates ◽  
Immersion Time ◽  
Moisture Absorption ◽  
Bending Strength ◽  
Experimental Results ◽  
Bending Tests ◽  
Three Point Bending ◽  
Damage Propagation ◽  
Effect Of Moisture

The effects of moisture content on the bending strength of T300/914 composite laminates that immersed in water for 7 days and 14 days was discussed in this paper. The three-point bending tests were conducted on the composite laminates. Experimental results reveal that the moisture content in the laminates increased with immersion time and that moisture absorption accelerated damage propagation in the composite laminates. The bending strength of the unaged, aged specimens were characterized and analyzed. Compared to the unaged specimens, the bending strength of the composite laminates immersed for 7 and 14 days decreased by 6.62% and 16.98%, respectively. The results revealed that the bending strength of the aged specimens decreased with the increasing immersion time.

scholarly journals Ballistic Impact Resistance of UHPC Plates Made with Hybrid Fibers and Low Binder Content

2021 ◽  
Vol 13 (23) ◽  
pp. 13410
Author(s):  
Paulo Rodrigo Dapper ◽  
Hinoel Zamis Ehrendring ◽  
Fernanda Pacheco ◽  
Roberto Christ ◽  
Giovanna Costella Menegussi ◽  
...  
Keyword(s):  
Impact Strength ◽  
Impact Energy ◽  
High Performance Concrete ◽  
Energy Levels ◽  
Ballistic Impact ◽  
Fiber Content ◽  
Thin Plates ◽  
Class Iii ◽  
Hybrid Fibers ◽  
Fiber Volume

This study assesses the ballistic impact strength of thin plates made of ultra-high-performance concrete (UHPC) with low cement content (250 kg/m3) and volumes of 80% steel and 20% polypropylene (PP) hybrid fibers. The plates were prepared with thicknesses of 30, 50, and 70 mm and fiber volume ratios of 1.5% and 3.0%. Compressive strength, flexural tensile strength, residual strength, and ballistic impact strength were determined using experimental methods. Test results showed that regardless of fiber content, the UHPC specimens prepared with the hybrid fibers showed similar performance against ballistic impact, exerting relatively low impact energy below 1000 J. The UHPC3.0 mixture made with 3.0% hybrid fiber content exhibited the best performance in terms of energy absorption and spalling resistance at impact energy levels greater than 4000 J. Plate sections with thicknesses of 7 mm showed class III performance (highest level), as recommended for military-based applications.

Effect of Moisture Absorption on the Bending Strength of Carbon/Epoxy Composites with Voids

2011 ◽  
Vol 311-313 ◽  
pp. 165-168
Author(s):  
A Ying Zhang ◽  
Jian She Zhang ◽  
Jia Zhi Wang ◽  
Di Hong Li ◽  
Dong Xing Zhang ◽  
...  
Keyword(s):  
Moisture Content ◽  
Water Uptake ◽  
Immersion Time ◽  
Room Temperature ◽  
Moisture Absorption ◽  
Bending Strength ◽  
Experimental Results ◽  
Epoxy Composites ◽  
Effect Of Moisture

The effects of voids on the bending strength of T300/914 laminates that exposed to room temperature, hygrothermal and drying environment was discussed in this paper. The experimental results revealed that the saturated moisture content and the rate of water uptake increased with porosity increasing from 0.71% to 1.50%, which proved that voids facilitate moisture absorption. The bending strength of the unaged, aged and dried specimens were characterized and analyzed. The results revealed that the bending strength of the aged specimens decreased with the increasing void contents and immersion time. Compared to the unaged specimens, the bending strength of the aged specimens decreased 13.33% and 18.78% with porosity of 0.71% and 1.50%, respectively. The bending strength of the dried specimens was higher than that of the aged specimens and lower than that of the unaged specimens in the case of similar porosity.

scholarly journals Water Absorption Behavior and Impact Strength of PVC/Wood Flour Composites

2010 ◽  
Vol 4 (3) ◽  
pp. 225-229 ◽  
Author(s):  
Gisele Iulianelli ◽  
◽  
Maria Bruno Tavares ◽  
Leandro Luetkmeyer ◽  
◽  
...  
Keyword(s):  
Impact Strength ◽  
Water Absorption ◽  
Moisture Absorption ◽  
Wood Flour ◽  
Chemical Constituents ◽  
Water Immersion ◽  
Control Sample ◽  
Maximum Water ◽  
The Difference ◽  
Wood Content

PVC/wood flour composites were prepared by compression molding using sapwood and heartwood from Angelin Pedra as filler. The composites specimens were subjected to water immersion and impact tests. The results showed that the water absorption of all composites increased slightly with increasing immersion time and wood content. However, the values were considerably low compared with control sample, common solid woods and wood plastic composites reported in literature. PVC/sapwood composites showed slightly higher values for moisture absorption ability due to the difference in chemical constituents’ ratio. PVC compound and PVC/sapwood composite containing 10 phr of wood flour exhibited maximum water absorption in 63 days and it corresponded to 0.25 % and 0.58 % weight gain, respectively. In relation to impact test, the results indicated that impact property was affected by wood content and less by wood type. Composites containing 10 phr of wood content showed greater impact strength (decreased by around 60 %) than those prepared with 25 and 40 phr of wood flour content (decreased approximately by 75 %). In general the composites prepared with 10 phr of wood flour content exhibited a better performance in both parameters measured in this study.

Effect of Moisture Absorption on the Residual Strength after Bending Fatigue of CFRP

2011 ◽  
Vol 415-417 ◽  
pp. 2142-2145
Author(s):  
A Ying Zhang ◽  
Di Hong Li ◽  
Cheng Li Liang ◽  
Jiu Si Jia ◽  
Dong Xing Zhang
Keyword(s):  
Moisture Content ◽  
Composite Laminates ◽  
Immersion Time ◽  
Moisture Absorption ◽  
Bending Strength ◽  
Fatigue Tests ◽  
Material Strength ◽  
Bending Fatigue ◽  
Residual Properties ◽  
Effect Of Moisture

This study investigates the effect of moisture content on the residual bending strength after bending fatigue of T300/914 composite laminates immersed in water for 7 days and 14 days. Displacement-controlled three-point bending fatigue tests were conducted on specimens. After 40,000 cycles the fatigue test was stopped and the residual properties were measured on the tested specimens. Reduction in material strength was found to depend on the level of moisture content. Experimental results reveal that the moisture content in the laminates increased with immersion time. Compared to the unaged specimens, the residual bending strength after bending fatigue decreased by 6.67% and 37.04%, respectively. The residual bending strength and strength retention decreased with increased immersion time.

Static and Fatigue Strength of Resin Transfer Molded Composites

2002 ◽  
Author(s):  
Youssef Hamidi ◽  
Levent Aktas ◽  
J. David Bladwin ◽  
M. Cengiz Altan
Keyword(s):  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Volume Fraction ◽  
Fatigue Behavior ◽  
Fatigue Loading ◽  
Fiber Content ◽  
Fiber Volume ◽  
Neat Polymer ◽  
Volume Fractions ◽  
Structural Applications

Fiber reinforced polymer composites are preferred in many structural applications for their ease of production and high specific strengths. Although fatigue loading is commonly encountered in structural applications, behavior of composites under cyclic loading is less understood compared to fatigue behavior of more conventional metals and their alloys. In this work, the response of resin transfer molded (RTM) glass/epoxy composites to static tensile and fatigue loading is investigated. Center-gated, disk shaped composites are fabricated using EPON 815C epoxy resin and EPICURE 3282 curing agent. A randomly oriented, planar glass fiber preform with 0.459kg/m2 surface density is used as the reinforcement material. Two and six layers of preforms are used to achieve 7.9 and 28.9% fiber volume fractions respectively. In addition, neat polymer parts are molded without performs to study the effect of fiber content on the tensile and fatigue behavior. Initially, ultimate tensile strength (UTS) and stiffness for three different fiber volume fractions (i.e., 0, 7.9, and 28.9%) are reported. Then, fatigue tests are conducted for stress level (σmax/UTS) of 0.5 and stress ratio (σmax/σmin) of 0.1 at a test frequency of 10 Hz. Loss of stiffness and cycles to failure are the two fatigue properties investigated. As the fiber volume fraction increased from 7.9 to 28.9%, the ultimate tensile strength and stiffness increased by 140 and 100%, respectively. During fatigue loading, the stiffness gradually dropped by approximately 13% for 7.9% and 28.9% fiber volume fractions. However, neat polymer samples did not show considerable decrease in stiffness during cycling. It is also shown that the number of cycles before failure significantly increased with the fiber content.

Impact Strength of Carbon Reinforced Epoxy Composite at Different Temperatures

2011 ◽  
Vol 264-265 ◽  
pp. 451-456 ◽  
Author(s):  
T.A. Lenda ◽  
S. Mridha
Keyword(s):  
Impact Strength ◽  
Impact Energy ◽  
Epoxy Composite ◽  
Charpy Impact ◽  
Fiber Content ◽  
Matrix Cracking ◽  
Fiber Volume ◽  
Fiber Splitting ◽  
Different Temperatures ◽  
The Impact

Charpy impact tests were conducted on carbon reinforced epoxy composites fabricated by hand lay-up method using 0.47, 0.56 and 0.66 carbon fiber volume fractions; tests were conducted at temperatures between -60oC to 60oC. The impact strength was found, in general, to increase when the samples were fractured at temperatures above 0oC and the impact strength decreased with the increase of fiber content. The impact energy absorption was highest of 270 KJm-2 with 47 vol% fiber when fractured at +60oC and it reduced to 130 KJm-2 at -60oC. With decreasing the fracture temperature and increasing the fiber content the impact strength reduced significantly. The reduction of impact energy was from 235 KJm-2 to 107 KJm-2 for 56 vol% fiber and from 196 KJm-2 to 90 KJm-2 for 66 vol% fiber when fractured at +60oC and -60oC, respectively. Failure occurred mostly by fiber delamination; fiber splitting and matrix cracking were also present. Delamination was more in specimens tested at -60oC while fiber splitting and matrix cracking were more when fractured at +60oC.

Effect of Voids on Moisture Absorption of CFRP Laminates in Hygrothermal Environment

2011 ◽  
Vol 301-303 ◽  
pp. 342-346
Author(s):  
A Ying Zhang ◽  
Jian She Zhang ◽  
Yu Cheng Li ◽  
Di Hong Li ◽  
Dong Xing Zhang ◽  
...  
Keyword(s):  
Moisture Content ◽  
Equilibrium State ◽  
Water Uptake ◽  
Immersion Time ◽  
Moisture Absorption ◽  
Dimensional Change ◽  
Cfrp Laminates ◽  
Width Direction ◽  
Length Direction ◽  
Hygrothermal Environment

The effect of voids on moisture absorption of T300/914 laminates was discussed in this paper. The experimental results revealed that the moisture content increases with the immersion time at first and then reach a pseudo equilibrium state for the compressive and bending specimens. The saturated moisture content and the rate of water uptake increased with porosity increasing from 0.71% to 1.50%, which proved voids accelerate moisture absorption. The geometry of the specimens influences the moisture behavior. The saturated moisture content increased with the decreasing width of the specimens. The most significant increase in dimensional change is in the thickness and length direction, followed by the width direction.

scholarly journals Study on the Moisture Absorption and Thermal Properties of Hygroscopic Exothermic Fibers and Related Interactions with Water Molecules

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 98 ◽  
Author(s):  
Yi Cui ◽  
Shuyi Gao ◽  
Ruiyun Zhang ◽  
Longdi Cheng ◽  
Jianyong Yu
Keyword(s):  
Moisture Content ◽  
Thermal Performance ◽  
Water Sorption ◽  
Moisture Absorption ◽  
Bound Water ◽  
Absorption Process ◽  
Heating Performance ◽  
Hygroscopic Behavior ◽  
Water Sorption Capacity ◽  
Main Factor

The aim of this paper is to study the hygroscopic behavior of hygroscopic exothermic fiber-based materials and to obtain a better understanding of the thermal performance of these fibers during the moisture absorption process. The temperature distribution of different kinds of hygroscopic exothermic fibers in the process of moisture absorption, observed by infrared camera, demonstrated two types of heating performance of these fibers, which might be related to its hygroscopic behavior. Based on the sorption isotherms, a Guggenheim-Anderson-de Boer (GAB) multi-layer adsorption model was selected as the optimal moisture absorption fitting model to describe the moisture absorption process of these fibers, which illustrated that water sorption capacity and the water–fiber/water–water interaction had a significant influence on its heating performance. The net isosteric heats of sorption decreased with an increase of moisture content, which further explained the main factor affecting the heat dissipation of fibers under different moisture contents. The state of adsorbed water and water vapor interaction on the fiber surface were studied by simultaneous thermal analysis (TGA-DSC) measurement. The percentage of bound and unbound water formation at low and high humidity had a profound effect on the thermal performance of fibers. It can therefore be concluded that the content of tightly bound water a strong water–fiber interaction was the main factor affecting the heating performance of fibers at low moisture content, and the content of loosely bound water reflected that water sorption capacity was the main factor affecting the heating performance of fibers at high moisture content. This was further proven by the heat of desorption.

scholarly journals RICE STRAW/THERMOPLASTIC COMPOSITE: EFFECT OF FILLER LOADING, POLYMER TYPE AND MOISTURE ABSORPTION ON THE PERFORMANCE

CERNE ◽  
2016 ◽  
Vol 22 (4) ◽  
pp. 449-456 ◽  
Author(s):  
Hossein Mohammadi ◽  
Seyedmohammad Mirmehdi ◽  
Lisiane Nunes Hugen
Keyword(s):  
Tensile Strength ◽  
Rice Straw ◽  
Moisture Absorption ◽  
Water Immersion ◽  
Filler Loading ◽  
Thermoplastic Composite ◽  
Modulus Of Rupture ◽  
Thermoplastic Composites ◽  
Composite Effect ◽  
Wet Condition

ABSTRAT Thermoplastic composites made with 45, 60 and 75% of rice straw as filler and two types of thermoplastics, virgin polyethylene (PE) and polypropylene (PP) were evaluated. The final boards were made with and without maleic anhydride modified polypropylene (MAPP) at 2% of the total weight of each specimen. The flexural and tensile strengths were measured for dry composites and also measured after 24 h of water immersion of the composites (wet condition). By increasing the filler content, the flexural and tensile strengths and also the density of the specimens decreased. The type of matrix (PE or PP) did not affect significantly the flexural strength, but PP led to higher values of tensile strength for low fiber loadings (45% and 60%). Coupling agents increased the flexural and tensile strength. After water immersion, modulus of elasticity and modulus of rupture were decreased, while tensile strength was less influenced.

Sign in / Sign up

Export Citation Format

Share Document