Redux is the generic name of a family of
phenol–formaldehyde/
polyvinyl–formal adhesives
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation.
The use of adhesives offers certain advant ...
developed by
Aero Research Limited
Aero Research Limited (ARL) was a British company that pioneered several new adhesives, intended initially for the aeronautical industry.
Formed in 1934 by Norman de Bruyne at Duxford, Cambridgeshire from an earlier company of his, the Cambridges ...
(ARL) at
Duxford
Duxford is a village in Cambridgeshire, England, about south of Cambridge. It is part of the Hundred Parishes area.
History
The village formed on the banks of the River Cam, a little below its emergence from the hills of north Essex. One of t ...
, UK, in the 1940s, subsequently produced by
Ciba (ARL). The brand name is now also used for a range of
epoxy
Epoxy is the family of basic components or cured end products of epoxy resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also coll ...
and bismaleimide adhesives manufactured by
Hexcel
Hexcel Corporation is an American public industrial materials company, based in Stamford, Connecticut. The company develops and manufactures structural materials. Hexcel was formed from the combination of California Reinforced Plastics (founded ...
. The name is a contraction of ''REsearch at DUXford''.
History
Devised at ARL by Dr.
Norman de Bruyne
Norman Adrian de Bruyne FRS was born in Punta Arenas Chile on 8 November 1904, and baptised on 19 March 1905 at the Anglican St. James Church, by the Rev. Edwin Aspinall. His father was Dutch and his mother English. He grew up in England, studi ...
and George Newell in 1941 for use in the aircraft industry, the adhesive is used for the
bonding of metal-to-metal and metal-to-wood structures. The adhesive system comprises a liquid phenolic resin and a PVF (PolyVinylFormal) thermoplastic powder.
The first formulation available was Redux Liquid E/Formvar, comprising a phenolic liquid (Redux Liquid E) and a PVF powder (
Formvar), and after its initial non-aviation related application of bonding
clutch
A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...
plates on
Churchill
Sir Winston Leonard Spencer Churchill (30 November 187424 January 1965) was a British statesman, soldier, and writer who served as Prime Minister of the United Kingdom twice, from 1940 to 1945 during the Second World War, and again from 1 ...
and
Cromwell
Oliver Cromwell (25 April 15993 September 1658) was an English politician and military officer who is widely regarded as one of the most important statesmen in English history. He came to prominence during the 1639 to 1651 Wars of the Three Ki ...
tank
A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engin ...
s, it was used by
de Havilland
The de Havilland Aircraft Company Limited () was a British aviation manufacturer established in late 1920 by Geoffrey de Havilland at Stag Lane Aerodrome Edgware on the outskirts of north London. Operations were later moved to Hatfield in H ...
from
1943 to the early 1960s, on, among other aircraft, the
Hornet
Hornets (insects in the genus ''Vespa'') are the largest of the eusocial wasps, and are similar in appearance to their close relatives yellowjackets. Some species can reach up to in length. They are distinguished from other vespine wasps by th ...
, the
Comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ar ...
and the derived
Nimrod
Nimrod (; ; arc, ܢܡܪܘܕ; ar, نُمْرُود, Numrūd) is a biblical figure mentioned in the Book of Genesis and Books of Chronicles. The son of Cush and therefore a great-grandson of Noah, Nimrod was described as a king in the land of ...
, and the
Dove
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
,
Heron
The herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera ''Botaurus'' and ''Ixobrychus ...
and
Trident
A trident is a three- pronged spear. It is used for spear fishing and historically as a polearm.
The trident is the weapon of Poseidon, or Neptune, the God of the Sea in classical mythology. The trident may occasionally be held by other marine ...
. It was also used by
Vickers
Vickers was a British engineering company that existed from 1828 until 1999. It was formed in Sheffield as a steel foundry by Edward Vickers and his father-in-law, and soon became famous for casting church bells. The company went public in 18 ...
on the
Viking
Vikings ; non, víkingr is the modern name given to seafaring people originally from Scandinavia (present-day Denmark, Norway and Sweden),
who from the late 8th to the late 11th centuries raided, pirated, traded and se ...
and by
Chance Vought on the
F7U Cutlass
The Vought F7U Cutlass is a United States Navy carrier-based jet fighter and fighter-bomber of the early Cold War era. It was a tailless aircraft for which aerodynamic data from projects of the German Arado and Messerschmitt companies, obtained ...
.
Typically, Redux would be used to affix stiffening
stringer
Stringer may refer to:
Structural elements
* Stringer (aircraft), or longeron, a strip of wood or metal to which the skin of an aircraft is fastened
* Stringer (slag), an inclusion, possibly leading to a defect, in cast metal
* Stringer (stairs), ...
s and doublers to
wing
A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is expres ...
and
fuselage
The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...
panels, the resulting panel being both stronger and lighter than a
rivet
A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...
ed structure. In the case of the Hornet it was used to join the
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
lower-wing skin to the wooden upper wing structure, and in the fabrication of the aluminium/wood main wing
spar
SPAR, originally DESPAR, styled as DE SPAR, is a Dutch multinational that provides branding, supplies and support services for independently owned and operated food retail stores. It was founded in the Netherlands in 1932, by Adriaan van Well, ...
, both forms of
composite
Composite or compositing may refer to:
Materials
* Composite material, a material that is made from several different substances
** Metal matrix composite, composed of metal and other parts
** Cermet, a composite of ceramic and metallic materials
...
construction made possible by the advent of Redux.
After initially supplying de Havilland only, ARL subsequently produced a refined form of ''Redux Liquid E/Formvar'' using a new liquid component known as Redux Liquid K6, and a finer-grade (smaller
particle
In the Outline of physical science, physical sciences, a particle (or corpuscule in older texts) is a small wikt:local, localized physical body, object which can be described by several physical property, physical or chemical property, chemical ...
-size) PVF powder, and this was later made generally available to the wider aircraft industry as Redux Liquid 775/Powder 775, so-named because it was sold for aircraft use to specification DTD 775
*. Available for general non-
aerospace
Aerospace is a term used to collectively refer to the atmosphere and outer space. Aerospace activity is very diverse, with a multitude of commercial, industrial and military applications. Aerospace engineering consists of aeronautics and astrona ...
use it was called Redux Liquid K6/Powder C.
''Redux Liquid 775/Powder 775'' was joined in
1954
Events
January
* January 1 – The Soviet Union ceases to demand war reparations from West Germany.
* January 3 – The Italian broadcaster RAI officially begins transmitting.
* January 7 – Georgetown-IBM experiment: The fir ...
by the subsequent Redux Film 775 system, used from
1962 by de Havilland (later
Hawker Siddeley
Hawker Siddeley was a group of British manufacturing companies engaged in aircraft production. Hawker Siddeley combined the legacies of several British aircraft manufacturers, emerging through a series of mergers and acquisitions as one of onl ...
and subsequently
British Aerospace
British Aerospace plc (BAe) was a British aircraft, munitions and defence-systems manufacturer. Its head office was at Warwick House in the Farnborough Aerospace Centre in Farnborough, Hampshire. Formed in 1977, in 1999 it purchased Marconi ...
) on the
DH.125 and
DH.146. Other users included
Bristol
Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city in ...
(on the
Britannia
Britannia () is the national personification of Britain as a helmeted female warrior holding a trident and shield. An image first used in classical antiquity, the Latin ''Britannia'' was the name variously applied to the British Isles, Great ...
),
SAAB
Saab or SAAB may refer to:
Brands and enterprises
* Saab Group, a Swedish aerospace and defence company, formerly known as SAAB, and later as Saab AB
** Datasaab, a former computer company, started as spin off from Saab AB
* Saab Automobile, a fo ...
(on the
Lansen &
Draken),
Fokker
Fokker was a Dutch aircraft manufacturer named after its founder, Anthony Fokker. The company operated under several different names. It was founded in 1912 in Berlin, Germany, and became famous for its fighter aircraft in World War I. In 1919 ...
(on the
F.27),
Sud Aviation (on the
Alouette II/III),
Breguet and
Fairchild Fairchild may refer to:
Organizations
* Fairchild Aerial Surveys, operated in cooperation with a subsidiary of Fairey Aviation Company
* Fairchild Camera and Instrument
* List of Sherman Fairchild companies, "Fairchild" companies
* Fairchild Fa ...
, the film-form having the advantage of greater gap-filling ability with no loss of strength over ''Redux Liquid 775/Powder 775'', allowing for wider tolerances in component-fit, as well as easier handling and use and controlled ratios of the liquid/powder components.
Other Redux adhesives available included "Redux 64", a solution of the phenolic liquid and PVF powder, used worldwide for bonding linings to brake shoes, pads and clutches.
The Redux range was subsequently expanded to include the current range of adhesives, both in single and two part paste systems and film forms, for both aerospace and industrial uses.
* DTD = ''Directorate of Technical Development''
Usage
To use Redux in its liquid/powder form, a thin film of the phenolic liquid is applied to both mating surfaces and then dusted with or dipped in the PVF powder to give an approximate ratio by weight of 1 part liquid to 2 parts powder. The coated joints are then allowed to stand for between 30 minutes and 72 hours, then the components are brought together under elevated pressure and temperature. The
curing process is by
condensation
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to ...
and a typical figure for ''Redux Liquid 775/Powder 775'' is 30 minutes at under a pressure of . This is not critical and variations in curing-time and/or temperature may be used to increase
shear
Shear may refer to:
Textile production
*Animal shearing, the collection of wool from various species
**Sheep shearing
*The removal of nap during wool cloth production
Science and technology Engineering
*Shear strength (soil), the shear strength ...
and
creep strength at temperatures above . Extending the curing cycle gives benefits in
fatigue strength at some cost in the room-temperature peel strength, the practical limit for
aluminium alloy
An aluminium alloy (or aluminum alloy; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two principal ...
s being approximately for one hour, due to the possibility of affecting the alloy's mechanical properties.
Performance (typical) Redux 775
*Lap shear strength at ambient temperature =
*
Young's Modulus (E) =
*
Shear modulus
In materials science, shear modulus or modulus of rigidity, denoted by ''G'', or sometimes ''S'' or ''μ'', is a measure of the elastic shear stiffness of a material and is defined as the ratio of shear stress to the shear strain:
:G \ \stackre ...
=
Strength of bonds to materials other than aluminium:
Tensile
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as ...
shear of
lap joint
A lap joint or overlap joint is a joint in which the members overlap.
Lap joints can be used to join wood, plastic, or metal. A lap joint can be used in woodworking for joining wood together.
A lap joint may be a full lap or half lap. In a ful ...
s at room temperature:
*Bright
mild steel of thickness - mean failing stress =
*
Stainless steel
Stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon, other nonmetals and metals to obtain other desired properties. Stainless steel's corros ...
of thickness - mean failing stress =
*
Magnesium alloy
Magnesium alloys are mixtures of magnesium (the lightest structural metal) with other metals (called an alloy), often aluminium, zinc, manganese, silicon, copper, rare earths and zirconium. Magnesium alloys have a hexagonal lattice structure, w ...
1 of thickness - mean failing stress =
*Commercially-pure
titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...
2 of thickness - mean failing stress =
1 = HK31A-H24
2 =
ICI Titanium 130
See also
*
Araldite Araldite is a registered trademark of Huntsman Advanced Materials (previously part of Ciba-Geigy) referring to their range of engineering and structural epoxy, acrylic, and polyurethane adhesives. Swiss manufacturers originally launched Araldite D ...
*
Aerolite
*
Tego film Tego film is an adhesive sheet, used in the manufacture of waterproof plywood. It is applied dry and cured by heat, which allows for high-quality laminates that are free from internal voids and warping. Tego film plywoods were used in aircraft manuf ...
References
*''Project 3 – Environmental Durability of Adhesive Bonds – Report No. 9 – Forensic Studies of Adhesive Joints – Part 2 Bonded Aircraft Structure'' by A. Beevers. September 1995
Usage on the de Havilland Comet*
ttp://www.hexcel.com/News/Press+Releases/Archives/Redux+Anniversary.htm Hexcel ''Redux film adhesive – 50th anniversary'' Press Releasebr>
Hexcel ''Redux 775 Product Data''
External links
a short article on Redux by N. A de Bruyne in a 1953 issue of ''Flight''
{{DEFAULTSORT:Redux (Adhesive)
Adhesives
Materials science
Aerospace engineering