A
sandwich structured composite is a special class of
composite materialComposite materials are engineered materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure.- History :The most primitive composite materials were straw...
s that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high
bendingIn engineering mechanics, bending characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to an axis of the element. The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or...
stiffnessStiffness is the resistance of an elastic body to deformation by an applied force. It is an extensive material property.-Definition:The stiffness, k, of a body is a measure of the resistance offered by an elastic body to deformation .whereIn the International System of Units, stiffness is typically...
with overall low
densityThe density of a material is defined as its mass per unit volume. The symbol of density is ρ .- Formula :Mathematically:where: is the density, is the mass, is the volume....
.
Open and closed cell structured
foamThe most general definition of foam is a substance that is formed by trapping many gas bubbles in a liquid or solid. It can also refer to anything that is analogous to such a phenomenon, such as quantum foam. Often the term is used in reference to polyurethane foam , XPS foam, Polystyrene, or many...
,
balsaBalsa is a large, fast-growing tree that can grow up to 30m tall. Balsa trees are native from southern Brazil and Bolivia north to southern Mexico however Ecuador has been the primary source of commercial Balsa. In recent years some Balsa has been plantation grown...
wood and
syntactic foamSyntactic foams are composite materials synthesized by filling a metal, polymer or ceramic matrix with hollow particles called microballoons. The presence of hollow particles results in lower density, higher strength, a lower coefficient of thermal expansion, and, in some cases, radar or sonar...
, and
composite honeycombComposite honeycomb is a material used as a core material in Sandwich structured composite structures.Composite honeycomb takes its name from its visual resemblance to a bee's honeycomb - a hexagonal sheet structure.-Manufacture:...
are commonly used core materials.
A
sandwich structured composite is a special class of
composite materialComposite materials are engineered materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure.- History :The most primitive composite materials were straw...
s that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high
bendingIn engineering mechanics, bending characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to an axis of the element. The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or...
stiffnessStiffness is the resistance of an elastic body to deformation by an applied force. It is an extensive material property.-Definition:The stiffness, k, of a body is a measure of the resistance offered by an elastic body to deformation .whereIn the International System of Units, stiffness is typically...
with overall low
densityThe density of a material is defined as its mass per unit volume. The symbol of density is ρ .- Formula :Mathematically:where: is the density, is the mass, is the volume....
.
Open and closed cell structured
foamThe most general definition of foam is a substance that is formed by trapping many gas bubbles in a liquid or solid. It can also refer to anything that is analogous to such a phenomenon, such as quantum foam. Often the term is used in reference to polyurethane foam , XPS foam, Polystyrene, or many...
,
balsaBalsa is a large, fast-growing tree that can grow up to 30m tall. Balsa trees are native from southern Brazil and Bolivia north to southern Mexico however Ecuador has been the primary source of commercial Balsa. In recent years some Balsa has been plantation grown...
wood and
syntactic foamSyntactic foams are composite materials synthesized by filling a metal, polymer or ceramic matrix with hollow particles called microballoons. The presence of hollow particles results in lower density, higher strength, a lower coefficient of thermal expansion, and, in some cases, radar or sonar...
, and
composite honeycombComposite honeycomb is a material used as a core material in Sandwich structured composite structures.Composite honeycomb takes its name from its visual resemblance to a bee's honeycomb - a hexagonal sheet structure.-Manufacture:...
are commonly used core materials.
GlassIn general Glass refers to a solid, brittle, transparent material, commonly used for windows, bottles, or eyewear. Examples of glassy materials include, but are not limited to, soda-lime glass, borosilicate glass, acrylic glass, sugar glass, Muscovy-glass, or aluminium oxynitride. The term glass...
or
carbon fiberCarbon fiber is a material consisting of extremely thin fibers about 0.005–0.010 mm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are more or less aligned parallel to the long axis of the fiber...
reinforced
laminateA laminate is a material constructed by uniting two or more layers of material together. The process of creating a laminate is lamination, which in common parlance refers to the placing of something between layers of plastic and sealing them with heat and/or pressure, usually with an adhesive...
s are widely used as skin materials.
Sheet metalSheet metal is simply metal formed into thin and flat pieces. It is one of the fundamental forms used in metalworking, and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material...
is also used as skin materials in some cases. The 1940
de HavillandThe de Havilland Aircraft Company was a British aviation manufacturer founded in 1920 when Airco, of which Geoffrey de Havilland had been chief designer, was sold to BSA by the owner George Holt Thomas. De Havilland then set up a company under his name in September of that year at Stag Lane...
MosquitoThe de Havilland Mosquito was a British combat aircraft that excelled in versatility during the Second World War. Originally conceived as an unarmed fast bomber, the Mosquito adapted to many other roles in during the air war in both the Pacific theatre of Operations and the European theatre,...
was built with sandwich composites, the balsa-wood core had on both sides plywood as the skin.
Metal composite material (MCM) is a type of sandwich formed from two thin skins of metal bonded to a plastic core in a continuous process under controlled pressure, heat, and tension.
Recycled paper is also now being used over a closed-cell recycled kraft honeycomb core, creating a lightweight, strong and fully repulpable composite board. This material is being used for applications including point-of-purchase displays, bulkheads, recyclable office furniture, exhibition stands and wall dividers.
To fix different panels, among other solutions, are normally use a transition zone, which is a gradual reduction of the core height, until the two fiber skins are in touch. In this place, the fixation can be made by means of bolts, rivets or adhesive.
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