Deep insight on the behaviour of short fibres within a composite
under uniaxial tensile

This work presents an investigation of the mechanical properties of a composite structure manufactured from polypropylene matrix reinforced with jute waste fibres collected from textile industry with extrusion followed by injection techniques. Mechanical tests under uniaxial strain shows that this lightweight vegetal fibre significantly enhanced the mechanical performances of the whole composite with a very slight quantity of compatibilizer which positively influences the final price of the composite. The fracture surfaces showed highly tethered as well as weakly anchored fibres to the matrix. Moreover, in order to have a deep insight on that anchoring behaviour, uniaxial tensile deformation was applied under Scanning Electron Microscopy and evidenced how the fibre/matrix interface plays a high role to strengthen the whole structure. The fibre and matrix interface is not simply resumed to high or weak anchoring but there is a combination of sticking and slipping of reinforcement on the polymeric walls.

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The Influence of Ultrasonic Energy on Chemical Treatment of Surface Properties and the Properties of Composites Made of Luffa Cylindrical Fiber-Polyester Resin

Journal of Engineering Materials and Technology ◽

10.1115/1.2969251 ◽

2008 ◽

Vol 130 (4) ◽

Cited By ~ 9

Author(s):

E. Dilara Koçak

Keyword(s):

Composite Structure ◽

Polyester Resin ◽

Unsaturated Polyester ◽

Natural Fibers ◽

Morphological Characteristics ◽

Mechanical Tests ◽

Cylindrical Fiber ◽

The Matrix ◽

Mechanical Performances ◽

Properties Of Composites

Producing composites from natural fibers is known to be common. These fibers benefit from their mechanical performances, low density, and their biodegradability. However, it is necessary for the fibers to form adhesion in the matrix. Therefore, it is necessary to apply a chemical process to the surface of the fibers. In this study, four different processes in conventional and ultrasonic energies were applied on luffa cylindrical fibers. At the end of the application, a composite structure was formed on the fibers that were obtained by using unsaturated polyester resin. The changes in the characteristics of the composite structure were recorded by mechanical tests, Fourier transform infrared, X-ray diffractometer, and their morphological characteristics by means of scanning electron microscopy. Considering all the results, formic acid and acetic acid process results were found to adequately modify the fiber surfaces.

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Prediction of the Fiber-Matrix Interface Failure due to Longitudinal Tensile Loading Using Finite Element Methods

MRS Proceedings ◽

10.1557/proc-365-229 ◽

1994 ◽

Vol 365 ◽

Author(s):

Hassan Mahfuz ◽

A.K.M. Ahsan Mian ◽

Uday K. Vaidya ◽

Timothy Brown ◽

Shaik Jeelani

Keyword(s):

Local Stress ◽

Tensile Loading ◽

Mechanical Tests ◽

Matrix Interface ◽

Interface Failure ◽

Strain Behavior ◽

The Matrix ◽

Fiber Matrix Interface ◽

Fiber Matrix ◽

Composite Response

ABSTRACTA 3D-unit cell for 0/90 laminated composites has been developed to predict the composite behavior under longitudinal tensile loading condition. 3D contact element has been used to model the fiber matrix interface. Two interface conditions, namely, infinitely strong and weakly bonded, are considered in the analysis. Both large displacement and plastic strain behavior for the matrix are considered to account for the geometric and material non-linearities. Investigations were carried out at three temperatures to compare the composite response obtained from mechanical tests at those temperatures. Stress-strain behavior and the local stress distributions at the fiber as well as at the matrix are presented, and their effects on the failure of the interface are discussed in the paper. The material under investigation was SiCf/Si3N4.

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Synchrotron x-ray Study of Elastic Phase Strains in the Bulk of an Externally Loaded Cu/Mo Composite

MRS Proceedings ◽

10.1557/proc-590-157 ◽

1999 ◽

Vol 590 ◽

Cited By ~ 2

Author(s):

A. Wanner ◽

D.C. Dunand

Keyword(s):

Plastic Deformation ◽

Load Transfer ◽

Tensile Deformation ◽

Copper Matrix ◽

High Energy ◽

Uniaxial Tensile ◽

X Rays ◽

Synchrotron Source ◽

Peak Broadening ◽

The Matrix

ABSTRACTHigh-energy, high-flux x-rays from a third-generation synchrotron source were used to measure average elastic strains in the bulk of 1.5 mm thick composites consisting of a copper matrix reinforced with 7.5 vol.% molybdenum particles. From the evolution of lattice strains in both phases during uniaxial tensile deformation, the internal load transfer between phases and reinforcement damage were characterized during elastic and plastic deformation of the composite. The graininess of the diffraction rings, which is related to the Bragg peak broadening, was quantified as a function of applied stress and related to plastic deformation in the matrix.

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Recycled HDPE-tetrapack composites. Isothermal crystallization, light scattering and mechanical properties

MRS Proceedings ◽

10.1557/opl.2013.252 ◽

2012 ◽

Vol 1485 ◽

pp. 77-82 ◽

Cited By ~ 2

Author(s):

A Parada-Soria ◽

HF Yao ◽

B Alvarado-Tenorio ◽

L Sanchez-Cadena ◽

A Romo-Uribe

Keyword(s):

Mechanical Properties ◽

Light Scattering ◽

Young’S Modulus ◽

Tensile Deformation ◽

Young's Modulus ◽

Ultimate Tensile Stress ◽

Uniaxial Tensile ◽

Scanning Calorimetry ◽

Slow Cooling ◽

The Matrix

ABSTRACTIn this research the thermal and mechanical properties of composites based on recycled high-density polyethylene (HDPE) and recycled Tetrapak have been investigated. The matrix and filler are recovered from landfills. Multicolor HDPE mixtures, with varying concentration of tetrapack flakes, are hot pressed, as well as single color HDPE flakes. Previous studies determine that the nature of the pigment (organics vs. inorganics) strongly influence the mechanical behavior of multicolor HDPE-tetrapack composites. Thus, this research focuses on single color HDPE hot pressed plaques. The kinetics of crystallization under isothermal conditions is determined by differential scanning calorimetry (DSC). The results show that the crystallization kinetics obeys the Avrami theory, and that the Avrami exponent is 1, irrespective of the pigment in use. Small-angle light scattering is applied to investigate the internal structure of the pigmented HDPE. SALS patterns show that the samples exhibited oriented morphologies. However, after melting and slow cooling under pressure the samples exhibit an isotropic morphology. This is confirmed by polarized optical microscopy. Mechanical properties such as Young’s modulus, yield stress and ultimate tensile stress are obtained under uniaxial tensile deformation at room temperature. For the single color HDPE plaques the Young’s modulus is reduced (after melting), suggesting that the anisotropic molecular chains contribute to the higher value of Young’s modulus.

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Blends containing core-shell impact modifiers Part 1. Structure and tensile deformation mechanisms (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1351/pac200173060897 ◽

2001 ◽

Vol 73 (6) ◽

pp. 897-912 ◽

Cited By ~ 14

Author(s):

C. B. Bucknall

Keyword(s):

Tensile Deformation ◽

Tensile Tests ◽

Mechanical Tests ◽

Glass Transitions ◽

Volume Increase ◽

Transmission Electron ◽

Technical Report ◽

The Matrix ◽

20 Nm

Two impact modifiers, based respectively on polybutadiene (PB) and poly(butyl acrylate-co-styrene) (PBA), are compared in blends with four glassy polymers: polycarbonate (PC), poly(methyl methacrylate) (PMMA), poly(styrene-co-acrylonitrile) (PSAN), and poly(vinyl chloride) (PVC). Dynamic mechanical tests show glass transitions at about -80 °C in PB and -15 °C in PBA. Both modifiers have grafted PMMA shells, which are seen in the transmission electron microscope (TEM) to be about 10 nm thick. The two-stage PB particles have 200-nm-diameter polybutadiene cores, whereas the three-stage PBA particles have 260-nm-diameter PMMA cores, with 20-nm thick PBA rubber inner shells. Under tension, the PB particles cavitate to form single voids on reaching a critical volume strain, and subsequently offer little resistance to dilatation. By contrast, tensile tests performed in situ in the TEM show that the PBA shells form fibrils that are anchored to the rigid core, and act as constraints on further dilatation: the stresses developed in the PBA fibrils can be sufficient to draw fibrils from both the PMMA core and the PSAN matrix. There is evidence that the PMMA shells can debond from the matrix both in cryogenic fracture and in fatigue at 23 °C. Tensile dilatometry shows that the PB particles cavitate at higher strains than the PBA particles, but that the PB particles then cause a rapid volume increase, leading to a low strain at break. By contrast, the PBA particles produce a more controlled dilatation, and higher strains to break. Later papers in this series treat the mechanical and rheological behavior of these blends in more detail.

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Physical and Mechanical Properties of the Reinforced Polyester: Characterization - Probabilistic Analysis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.482.67 ◽

2011 ◽

Vol 482 ◽

pp. 67-78 ◽

Cited By ~ 2

Author(s):

Kamal Ait Tahar ◽

Nora Harb

Keyword(s):

Probabilistic Models ◽

Physical And Mechanical Properties ◽

Mechanical Tests ◽

Strength Distribution ◽

Experimental Results ◽

Spectrometric Analysis ◽

X Rays ◽

The Matrix ◽

Mechanical Performances ◽

The Cost

The specific properties of material, such as resistance, the cost and the weight, become key factors in the decision making and the choice of vulgarization of material in its industrial and technological aspect. The choice of a resinous system used like stamps in the design of composites, depends on the mechanical performances and the cost of the resin. Currently the prohibitory cost of composite materials slows down the rise of their applications in certain technical fields. In this study, the physical and the mechanical characterization is presented, bearing on the resin of the type RESOW 55 E reinforced out of powders of different nature at different rate. The results of the mechanical tests carried out, show clearly, that the fracture is strongly influenced by the type and the rate of powder added in the matrix. In reinforcement, according to the results obtained with x-rays, one notes that there are no new chemical compounds formed in elaborate materials. The presence of powder does not modify the structure of polymer and that is confirmed by the x-rays analysis and spectrometric analysis. Based on experimental results, a model of Weibull strength distribution function has been established for each specimen. Finally, a confrontation of the theoretical and experimental results is carried out, based on probabilistic models.

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Analysis of Magnetic Anisotropy and Non-Homogeneity of S235 Ship Structure Steel after Plastic Straining by the Use of Barkhausen Noise

Materials ◽

10.3390/ma13204588 ◽

2020 ◽

Vol 13 (20) ◽

pp. 4588

Author(s):

Martin Jurkovič ◽

Tomáš Kalina ◽

Katarína Zgútová ◽

Miroslav Neslušan ◽

Martin Pitoňák

Keyword(s):

Magnetic Anisotropy ◽

Tensile Deformation ◽

Uniaxial Tensile ◽

Barkhausen Noise ◽

Noise Emission ◽

Ship Structure ◽

Residual Stress State ◽

Reliable Monitoring ◽

The Matrix ◽

Non Destructive

This study investigates the microstructure, residual stress state, and the corresponding magnetic anisotropy of the ship structure samples made of S235 steel after uniaxial tensile deformation. A non-destructive magnetic technique based on Barkhausen noise is employed for fast and reliable monitoring of samples exposed to the variable degrees of plastic straining. It was found that the progressively developed plastic straining of the matrix results in an alteration of the easy axis of magnetization, stress anisotropy (expressed in residual stresses state) as well as the corresponding Barkhausen noise emission. Moreover, remarkable non-homogeneity can be found within the plastically strained region, especially when the localized plastic straining takes place.

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Maximum shear stress-controlled uniaxial tensile deformation and fracture mechanisms and constitutive relations of Sn–Pb eutectic alloy at cryogenic temperatures

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141523 ◽

2021 ◽

pp. 141523

Author(s):

Xiaoliang Ji ◽

Qi An ◽

Yiping Xia ◽

Rong An ◽

Rui Zheng ◽

...

Keyword(s):

Shear Stress ◽

Eutectic Alloy ◽

Tensile Deformation ◽

Constitutive Relations ◽

Maximum Shear Stress ◽

Uniaxial Tensile ◽

Fracture Mechanisms ◽

Cryogenic Temperatures ◽

Deformation And Fracture

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A Flow Stress Model of 300M Steel for Isothermal Tension

Materials ◽

10.3390/ma14020252 ◽

2021 ◽

Vol 14 (2) ◽

pp. 252

Author(s):

Rongchuang Chen ◽

Shiyang Zhang ◽

Xianlong Liu ◽

Fei Feng

Keyword(s):

Flow Stress ◽

Constitutive Model ◽

Tensile Deformation ◽

Flow Behavior ◽

Tensile Tests ◽

Uniaxial Tensile ◽

Model Parameters ◽

Average Deviation ◽

Cross Sectional ◽

300M Steel

To investigate the effect of hot working parameters on the flow behavior of 300M steel under tension, hot uniaxial tensile tests were implemented under different temperatures (950 °C, 1000 °C, 1050 °C, 1100 °C, 1150 °C) and strain rates (0.01 s−1, 0.1 s−1, 1 s−1, 10 s−1). Compared with uniaxial compression, the tensile flow stress was 29.1% higher because dynamic recrystallization softening was less sufficient in the tensile stress state. The ultimate elongation of 300M steel increased with the decrease of temperature and the increase of strain rate. To eliminate the influence of sample necking on stress-strain relationship, both the stress and the strain were calibrated using the cross-sectional area of the neck zone. A constitutive model for tensile deformation was established based on the modified Arrhenius model, in which the model parameters (n, α, Q, ln(A)) were described as a function of strain. The average deviation was 6.81 MPa (6.23%), showing good accuracy of the constitutive model.

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