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Jack R. Vinson

Bio: Jack R. Vinson is an academic researcher from University of Delaware. The author has contributed to research in topics: Shell (structure) & Sandwich-structured composite. The author has an hindex of 30, co-authored 168 publications receiving 8303 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, a linear elasticity solution for the adhesive layer is developed, and it is shown that the longitudinal tensile stresses are negligible and that the shear stress state does not vary through the thickness of the adhesive layers.

29 citations

Journal ArticleDOI
TL;DR: A review of the literature dealing with mechanical fastening of polymer matrix composite structures can be found in this paper, where the authors provide an overall introduction for detailed study of the referenced documents as well as others.
Abstract: In structures composed of polymer materials and polymer matrix composite materials, components must be joined such that the overall structure retains its structural integrity while it is performing its intended function which can include both mechanical loads (static and dynamic) and environmental loads (temperature and humidity). The use of composite materials in complex structures almost always reduces the number of components in the structures compared to the use of metallic alloys for the same structure. Thus, using composite materials not only results in great savings in weight, but also through a reduced number of joining operations, results in significant savings In assembly, inspection, parts storage, and movement, resulting in increased reliability and lower cost. Yet joining is still required. Joining metallic structures is a mature technology involving riveting, bolting, welding, glueing, brazing, soldering, and other methods. However, for most polymer matrix composites only adhesive bonding and mechanical fastening can be utilized. Attention has been given recently, however, to localized welding of thermoplastic polymer matrix composites. Inherently, adhesive bonding is preferable to mechanical fastening because of the continuous connection, whereas in drilling holes for bolts or rivets, fiber or other reinforcements are cut, and large stress concentrations occur at each discrete fastener hole. However, in many structures, it is necessary to employ mechanical fasteners in order to remove components or to have access to the interior of the structure. Hence, both adhesive bonding and mechanical fastening are important in joining structural components of polymer or polymer matrix materials. The following is a review of much of the literature dealing with mechanical fastening of polymer matrix composite structures. Hopefully, it provides an overall introduction for detailed study of the referenced documents as well as others, and a catalyst for further research.

29 citations

Journal ArticleDOI
TL;DR: In this article, a solution methodology to model adhesively bonded joints which is capable of handling the important effects of substrate asymmetry, anisotropy, thickness variation, transverse shear deformation, hygrothermal growth, and complicated models for the adhesive layer can prove to be very unwieldy.

27 citations

Journal ArticleDOI
TL;DR: In this article, an analytical model for composite laminated plates of general layup with either isotropic or anisotropic active layers is derived using the variational principle of virtual work along with the classical plate and lamination theories.
Abstract: The objective of this paper is to examine the feasibility of using monolithic, directed, or fibrous piezoelectric smart materials to control the shape of a subsonic projectile fin during flight. To achieve this goal, an analytical model for composite laminated plates of general layup with either isotropic or anisotropic active layers is derived. The mathematical formulation uses the variational principle of virtual work along with the classical plate and lamination theories and the anisotropic piezoelectric constitutive equations. A solution procedure that adopts the concepts of the extended Kantorovich method and imposes them on the variational ("weak") form of the active plate problem is derived. The results of the proposed model are compared with those of other classical approximated solutions, as well as results of finite element analysis. Finally, the derived model is used for the quantitative examination of four basic design concepts for twist actuation and shape control of the investigated fin. The...

27 citations


Cited by
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Journal ArticleDOI
TL;DR: This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them, and summarizes cellulOSE nanoparticles in terms of particle morphology, crystal structure, and properties.
Abstract: This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).

4,920 citations

Journal ArticleDOI
TL;DR: In this paper, a scaling analysis is performed to demonstrate that the effectiveness of actuators is independent of the size of the structure and evaluate various piezoelectric materials based on their effectiveness in transmitting strain to the substructure.
Abstract: This work presents the analytic and experimental development of piezoelectric actuators as elements of intelligent structures, i.e., structures with highly distributed actuators, sensors, and processing networks. Static and dynamic analytic models are derived for segmented piezoelectric actuators that are either bonded to an elastic substructure or embedded in a laminated composite. These models lead to the ability to predict, a priori, the response of the structural member to a command voltage applied to the piezoelectric and give guidance as to the optimal location for actuator placement. A scaling analysis is performed to demonstrate that the effectiveness of piezoelectric actuators is independent of the size of the structure and to evaluate various piezoelectric materials based on their effectiveness in transmitting strain to the substructure. Three test specimens of cantilevered beams were constructed: an aluminum beam with surface-bonded actuators, a glass/epoxy beam with embedded actuators, and a graphite/epoxy beam with embedded actuators. The actuators were used to excite steady-state resonant vibrations in the cantilevered beams. The response of the specimens compared well with those predicted by the analytic models. Static tensile tests performed on glass/epoxy laminates indicated that the embedded actuator reduced the ultimate strength of the laminate by 20%, while not significantly affecting the global elastic modulus of the specimen.

2,719 citations

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TL;DR: An overview of recent progress in the area of cellulose nanofibre-based nanocomposites is given in this article, with particular emphasis on applications, such as reinforced adhesives, to make optically transparent paper for electronic displays, to create DNA-hybrid materials, to generate hierarchical composites and for use in foams, aerogels and starch nanocom composites.
Abstract: This paper provides an overview of recent progress made in the area of cellulose nanofibre-based nanocomposites. An introduction into the methods used to isolate cellulose nanofibres (nanowhiskers, nanofibrils) is given, with details of their structure. Following this, the article is split into sections dealing with processing and characterisation of cellulose nanocomposites and new developments in the area, with particular emphasis on applications. The types of cellulose nanofibres covered are those extracted from plants by acid hydrolysis (nanowhiskers), mechanical treatment and those that occur naturally (tunicate nanowhiskers) or under culturing conditions (bacterial cellulose nanofibrils). Research highlighted in the article are the use of cellulose nanowhiskers for shape memory nanocomposites, analysis of the interfacial properties of cellulose nanowhisker and nanofibril-based composites using Raman spectroscopy, switchable interfaces that mimic sea cucumbers, polymerisation from the surface of cellulose nanowhiskers by atom transfer radical polymerisation and ring opening polymerisation, and methods to analyse the dispersion of nanowhiskers. The applications and new advances covered in this review are the use of cellulose nanofibres to reinforce adhesives, to make optically transparent paper for electronic displays, to create DNA-hybrid materials, to generate hierarchical composites and for use in foams, aerogels and starch nanocomposites and the use of all-cellulose nanocomposites for enhanced coupling between matrix and fibre. A comprehensive coverage of the literature is given and some suggestions on where the field is likely to advance in the future are discussed.

2,214 citations

Journal ArticleDOI
TL;DR: The most important members of the hexaferrite family are shown below, where Me = a small 2+ ion such as cobalt, nickel, or zinc, and Ba can be substituted by Sr: • M-type ferrites, such as BaFe12O19 (BaM or barium ferrite), SrFe 12O19(SrM or strontium ferite), and cobalt-titanium substituted M ferrite, Sr- or BaFe 12−2xCoxTixO19, or CoTiM as discussed by the authors.

1,855 citations

Journal ArticleDOI
TL;DR: The numerical implementation of the model of brittle fracture developed in Francfort and Marigo (1998) is presented in this paper, where various computational methods based on variational approximations of the original functional are proposed.
Abstract: The numerical implementation of the model of brittle fracture developed in Francfort and Marigo (1998. J. Mech. Phys. Solids 46 (8), 1319–1342) is presented. Various computational methods based on variational approximations of the original functional are proposed. They are tested on several antiplanar and planar examples that are beyond the reach of the classical computational tools of fracture mechanics.

1,617 citations