Ballistic impact response of carbon/epoxy tubes with variable nanosilica content

2017 ◽  
Vol 52 (12) ◽  
pp. 1589-1604 ◽  
Author(s):  
Aniruddh Vashisth ◽  
Charles E Bakis ◽  
Charles R Ruggeri ◽  
Todd C Henry ◽  
Gary D Roberts
Keyword(s):  
Fracture Toughness ◽  
Shear Strength ◽  
Glass Transition ◽  
Transition Temperature ◽  
Impact Damage ◽  
Mass Density ◽  
Impact Response ◽  
Residual Shear Strength ◽  
Damage Area ◽  
The Matrix

Laminated fiber reinforced polymer composites are known for high specific strength and stiffness in the plane of lamination, yet relatively low out-of-plane impact damage tolerance due to matrix dominated interlaminar mechanical properties. A number of factors including the toughness of the matrix can influence the response of composites to impact. The objective of the current investigation is to evaluate the ballistic impact response of carbon/epoxy tubes with variable amounts of nanosilica particles added to the matrix as a toughening agent. Mass density, elastic modulus, glass transition temperature and Mode I fracture toughness of the matrix materials were measured. Tubes manufactured with these matrix materials were ballistically impacted using a round steel projectile aimed at normal incidence across the major diameter. After impact, the tubes were nondestructively inspected and subjected to mechanical tests to determine the residual shear strength in torsion. Increasing concentrations of nanosilica monotonically increased the modulus and fracture toughness of the matrix materials. Tubes with nanosilica had smaller impact damage area, higher residual shear strength, and higher energy absorbed per unit damage area versus control materials with no nanosilica. Overall, the addition of nanosilica improved the impact damage resistance and tolerance of carbon/epoxy tubes loaded in torsion, with minimal adverse effects on mass density and glass transition temperature.

scholarly journals Evaluation of Interfacial Fracture Toughness and Interfacial Shear Strength of Typha Spp. Fiber/Polymer Composite by Double Shear Test Method

Materials ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2225 ◽  
Author(s):  
Ikramullah ◽  
Samsul Rizal ◽  
Yoshikazu Nakai ◽  
Daiki Shiozawa ◽  
H.P.S. Abdul Khalil ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Shear Strength ◽  
Interfacial Shear Strength ◽  
Epoxy Composite ◽  
Interfacial Fracture ◽  
Interfacial Shear ◽  
Composite Model ◽  
Interfacial Fracture Toughness ◽  
Double Shear ◽  
The Matrix

The aim of this paper is to evaluate the Mode II interfacial fracture toughness and interfacial shear strength of Typha spp. fiber/PLLA and Typha spp. fiber/epoxy composite by using a double shear stress method with 3 fibers model composite. The surface condition of the fiber and crack propagation at the interface between the fiber and the matrix are observed by scanning electron microscope (SEM). Alkali treatment on Typha spp. fiber can make the fiber surface coarser, thus increasing the value of interfacial fracture toughness and interfacial shear strength. Typha spp. fiber/epoxy has a higher interfacial fracture value than that of Typha spp. fiber/PLLA. Interfacial fracture toughness on Typha spp. fiber/PLLA and Typha spp. fiber/epoxy composite model specimens were influenced by the matrix length, fiber spacing, fiber diameter and bonding area. Furthermore, the interfacial fracture toughness and the interfacial fracture shear stress of the composite model increased with the increasing duration of the surface treatment.

Improvement of fracture toughness and glass transition temperature of DGEBA-based epoxy systems using toughening and crosslinking modifiers

2018 ◽  
Vol 59 (1) ◽  
pp. 86-95 ◽  
Author(s):  
Katja Utaloff ◽  
Martin Heinz Kothmann ◽  
Michael Ciesielski ◽  
Manfred Döring ◽  
Thomas Neumeyer ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Epoxy Systems

scholarly journals On the Combined Effect of Both the Reinforcement and a Waste Based Interfacial Modifier on the Matrix Glass Transition in iPP/a-PP-pPBMA/Mica Composites

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2606
Author(s):  
Jesús-María García-Martínez ◽  
Emilia P. Collar
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Atactic Polypropylene ◽  
Complex Character ◽  
The Matrix ◽  
Maleamic Acid ◽  
Interfacial Modifier ◽  
Key Parameter

This work deals with the changes of the glass transition temperature (Tg) of the polymer in polypropylene/mica composites due to the combined and synergistic effect of the reinforcement and the interfacial modifier. In our case, we studied the effect on Tg of platy mica and an interfacial modifier with p-phenylen-bis-maleamic acid (pPBMA) grafted groups onto atactic polypropylene (aPP-pPBMA). This one contains 5.0 × 10−4 g·mol−1 (15% w/w) grafted pPBMA and was previously obtained by the author’s labs by using industrial polymerization wastes (aPP). The objective of the article must be perceived as two-fold. On one hand, the determination of the changes in the glass transition temperature of the isotactic polypropylene phase (iPP) due to both the reinforcement and the agent as determined form the damp factor in DMA analysis. On the other hand, forecasting the variation of this parameter (Tg) as a function of both the interfacial agent and reinforcement content. For such purposes, and by assuming the complex character of the iPP/aPP-pPBMA/Mica system, wherein interaction between the components will define the final behaviour, a Box–Wilson experimental design considering the amount of mica particles and of interface agent as the independent variables, and the Tg as the dependent one, has been used. By taking in mind that the glass transition is a design threshold for the ultimate properties of parts based in this type of organic–inorganic hybrid materials, the final purpose of the work is the prediction and interpretation of the effect of both variables on this key parameter.

Elastomer Modification of Structural Adhesives

1985 ◽  
Vol 58 (3) ◽  
pp. 622-636 ◽  
Author(s):  
Alphonsus V. Pocius
Keyword(s):  
Fracture Toughness ◽  
Shear Strength ◽  
Physical Properties ◽  
Yield Stress ◽  
Peel Strength ◽  
Phase System ◽  
Two Phase ◽  
Structural Adhesives ◽  
Thermosetting Polymers ◽  
The Matrix

Abstract An attempt has been made to review the highlights of the chemistry and physical properties of the rubber modification of structural thermosetting polymers that are used as adhesives. The elastomers are added in order to improve the characteristics of these structural thermosets such that they would be more useful as structural adhesives. The addition of an elastomer acts to increase the resistance of the structural thermoset to crack propogation. The resistance to crack propogation is obtained either by plasticization to increase the ductility of the thermoset or by generation of a two-phase system where the structural polymer forms a matrix in which the phase-separated elastomeric particles are imbedded. In the case of flexibilization by plasticization, the increase in peel strength (fracture toughness) is accompanied by a decrease in shear strength (modulus) at high temperatures. In the case of the two phase system, the matrix properties are unaffected for the most part, and increases in peel strength are not accompanied by significant decreases in high-temperature shear strength. In the case of flexibilization, the increase in fracture toughness is accomplished by increasing the ductility of the resin while in the case of the two-phase system, the rubber particles act as stress concentrators to cause conditions of exceeding the yield stress of the matrix near the particles. Exceeding the yield stress increases the amount of plastic deformation of the matrix. We have briefly reviewed the chemistry and physical properties of phenolic, epoxy, acrylic, and polyimide structural adhesives and their modification with vinyl, nitrile, acrylic, siloxane, and other types of elastomers.

scholarly journals Multiscale Characterization of Nanoengineered Fiber-Reinforced Composites: Effect of Carbon Nanotubes on the Out-of-Plane Mechanical Behavior

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Carlos Medina ◽  
Eduardo Fernandez ◽  
Alexis Salas ◽  
Fernando Naya ◽  
Jon Molina-Aldereguía ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Fracture Toughness ◽  
Shear Strength ◽  
Mechanical Behavior ◽  
Matrix Interface ◽  
Short Beam ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs.

INFLUENCE OF MULTIPLE CURING ON MECHANICAL PROPERTIES OF EPOXY MATRIX AND ITS ADHESION TO FIBERS

2021 ◽  
pp. 12-19
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Mechanical Behavior ◽  
Adhesive Strength ◽  
Epoxy Matrix ◽  
Steel Wire ◽  
Curing Temperature ◽  
The Matrix

Adhesive strength of «epoxy binder-steel wire» joints and the mechanical behavior of the binder during multiple repeated curing have been investigated. It is shown that when the curing temperature is considerably higher than the glass transition temperature of the binder, the adhesive strength decreases monotonically with an increase in the number of curing cycles. In this case the mechanical properties of the matrix also decrease. Possible mechanisms of the observed changes are discussed.

Vinylpyridinium ionomers. III. Influence of the matrix glass transition temperature on the dynamic mechanical properties of random acrylate-based systems

1990 ◽  
Vol 68 (7) ◽  
pp. 1228-1232 ◽  
Author(s):  
Denis Duchesne ◽  
Adi Eisenberg
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Butyl Acrylate ◽  
Matrix Material ◽  
Ethyl Acrylate ◽  
Dynamic Mechanical Properties ◽  
Dynamic Mechanical ◽  
The Matrix

The thermal and dynamic mechanical properties of random butyl acrylate- and plasticized ethyl acrylate-based vinylpyridinium ionomers have been investigated. The properties of the ionomers were found to be dependent on the glass transition temperature of the matrix material. Ionomers having a glass transition temperature lower than ca. 25 °C exhibited all the features associated with the presence of phase-separated microdomains or clusters while the materials with higher glass transition temperatures were not. It was also observed that the dispersion associated with the vinylpyridinium clusters for a butyl acrylate-based ionomer with 12 mol% of ionic units occurs at ca. 25 °C. This value is very close to that observed previously by Otocka and Eirich in their study of a butadiene-based vinylpyridinium ionomer with the same ion content. Keywords: ionomers, plasticization, clustering, glass transition, dynamic mechanical properties.

Silica-Polymer Core-Shell Particles for Fabrication of Poly(methyl methacrylate) Composite Materials

2012 ◽  
Vol 531 ◽  
pp. 153-156
Author(s):  
Ren Gui Peng ◽  
Cheng En He ◽  
Wei Tang ◽  
Yue E Liu ◽  
Ying Kui Yang
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Composite Materials ◽  
Glass Transition Temperature ◽  
Methyl Methacrylate ◽  
Interfacial Adhesion ◽  
Core Shell ◽  
Poly Methyl Methacrylate ◽  
The Matrix ◽  
Shell Particles

Poly(n-butyl acrylate) grafted silica nanoparticles were compounded with poly(methyl methacrylate) to yield silica/polymer composites with the improved dispersion of silica and interfacial adhesion with the matrix, thus showing increases in storage modulus and glass transition temperature.

Sign in / Sign up

Export Citation Format

Share Document