Sandwich-structured composite
In the sandwich construction materials with different properties in layers to form a component or semi-finished are assembled. The name comes from the snack that also consists of several layers called sandwich ( to German folding sandwich ). Typically is the sequence of the core - coating layer covering layer.
Construction and statics
As a design example, the sandwich construction is a form of lightweight construction, in which the components of the force-absorbing solid surface layers exist, which are held by a relatively soft, mostly mild, nuclear material at a distance. These parts are at a low weight very resistant to bending and beulsteif. Your calculation is performed in the building according to the linear sandwich theory.
The core may be made of paper honeycomb, foam (hard foam), mineral wool or balsa. It transfers occurring shear forces and supports the outer layers. Often the thermal and acoustic insulation property of very lightweight core materials will be used. As layers, among other sheet (blocking ) or wood fiber composites are used. Often force application points are provided with reinforcements.
Application
Applications include sport boats, aircraft parts ( fuselage, wing shells ), railway cars, surf boards ( polyurethane ), and rotor blades for wind turbines.
Sandwich panels with honeycomb core made of aramid fibers with keytops Glasfaserprepregs are often used as walls for galleys and toilets in airplanes.
In construction, prefabricated sandwich panels are used consisting of a reinforced concrete shell, thermal insulation and a facing made of brick or concrete. In addition, composite panels with metal facings and an intermediate insulation are referred to as sandwich panel or sandwich. Room doors are often made of plywood layers with paper honeycomb core.
For use on production halls there are transparent sandwich elements, so that the daylight also in the production area can still be used. This achieves a better illumination of the workplace that brings an energy-saving potential with it, because you can at times completely abandon artificial lighting.
In shipbuilding, this construction is already today, especially in recreational craft very common. In the United Shipbuilding sandwich construction promises to bring more safety, especially at the tankers. Even existing ships can be fitted retrospectively.
In vehicle exterior walls are used in sandwich construction including in cooling box bodies of commercial vehicles and motorhomes.
In the automotive industry the sandwich construction is used to achieve a better use of space. Thus, there are, for example, at the Mercedes -Benz A-Class, some aggregates in the vehicle floor. Before the establishment of Israel, the Jews retrofitted lack of real tanks trucks to sandwich armored car to.
In the manufacture of ski sandwich construction allows for great variability in terms of material and construction costs: the spectrum ranges from simple foam core for beginner's to the small series for FIS Weltcupski with glued core.