IntroductionNatural honeycomb structures include beehives, honeycomb weathering in rocks, tripe, and bone. Man-made honeycomb structures include sandwich composites with honeycomb cores. Man-made honeycomb structures are manufactured by using a variety of different materials, depending on the intended application and required characteristics, from paper or thermoplastics, used for low strength and stiffness for low load applications, to high strength and stiffness for high performance applications, from aluminum or fiber reinforced plastics. The strength of laminated or sandwich panels depends on the size of the panel, facing material used and the number or density of the honeycomb cells within it. Honeycomb composites are used widely in many industries, from aerospace industries, automotive and furniture to packaging and logistics. The material takes its name from its visual resemblance to a bee's honeycomb - a hexagonal sheet structure.
HistoryThe hexagonal comb of the honeybee has been admired and wondered about from ancient times on. The first man-made honeycomb is said to have been manufactured by Daedalus from gold by lost wax casting more than 3000 years ago. Marcus Varro reports that the Greek geometricians Euclid and Zenodorus found that the hexagon shape makes most efficient use of space and building materials. The interior structure and hidden chambers of the Roman Pantheon dome is an early example of a honeycomb structure. Galileo Galilei discusses in 1638 the resistance of hollow solids:
Art, and nature even more, makes use of these in thousands of operations in which robustness is increased without adding weight, as is seen in the bones of birds and in many stalks that are light and very resistant to bending and breakingRobert Hook discovers in 1665 that the natural cellular structure of cork is similar to the hexagonal honeybee comb and Charles Darwin states in 1859 that;
The comb of the hive-bee, as far as we can see, is absolutely perfect in economizing labour and waxFirst paper honeycomb structures might have been made by the Chinese 2000 years ago for ornaments, but no reference for this has been found. Paper honeycombs and the expansion production process has been invented in Halle/Saale in Germany by Hans Heilbrun in 1901 for decorative applications. First honeycomb structures from corrugated metal sheets had been proposed for bee keeping in 1890. For the same purpose, as foundation sheets to harvest more honey, a honeycomb moulding process using a paper paste glue mixture had been patented in 1878. The three today still used basic honeycomb production techniques: expansion, corrugation and moulding where already developed by 1901 for non-sandwich applications. Hugo Junkers first explored the idea of a honeycomb core within a laminate structure. He proposed and patented the first honeycomb cores for aircraft application in 1915. He described in detail his concept to replace the fabric covered aircraft structures by metal sheets and reasoned that a metal sheet can also be loaded in compression if it is supported at very small intervals by arranging side by side a series of square or rectangular cells or triangular or hexagonal hollow bodies. The problem of bonding a continuous skin to cellular cores led Junkers later to the open corrugated structure, which could be riveted or welded together. The first use of honeycomb structures for structural applications had been independently proposed for building application and published already in 1914. In 1934 Edward G. Budd patented a welded steel honeycomb sandwich panel from corrugated metal sheets and Claude Dornier aimed 1937 to solve the core-skin bonding problem by rolling or pressing a skin which is in a plastic state into the core cell walls. The first successful structural adhesive bonding of honeycomb sandwich structures was achieved by Norman de Bruyne of Aero Research Limited, who patented an adhesive with the right viscosity to form resin fillets on the honeycomb core in 1938. The North American XB-70 Valkyrie made extensive use of stainless steel honeycomb panels using a brazing process they developed.
ManufactureComposite honeycomb structures have been used in numerous engineering and scientific applications.
|Racing shells||Sport||Vespoli, Janousek Racing Boats|
|Gliders||Aerospace||Schleicher ASW 19, Solar Impulse Project|
|Helicopters||Aerospace||Kamov Ka-25, Bell 533, Westland Lynx|
|Jet aircraft||Aerospace||General Dynamics/Grumman F-111B, F-111 Aardvark|
|Rocket substructure||Aerospace||Saturn V Instrument Unit, Mars Exploration Rover, S-520|
|Loudspeaker technology||Audio||Loudspeaker Driver design, Woofer|
|Telescope mirror structure||Aerospace||Hubble Space Telescope
|Automobile structure||Automotive||Panther Solo, Dome F105, Bluebird-Proteus CN7, Ferrari F50|
There are no differences between the 5 June, 2012 @ 8:54 revision and the current revision. (Maybe only post meta information was changed.)