Explosion welding
Encyclopedia
Explosion welding is a solid state process
where welding
is accomplished by accelerating one of the components at extremely high velocity through the use of chemical explosives. This process is most commonly utilized to clad carbon steel plate with a thin layer of corrosion
resistant material (e.g., stainless steel
, nickel
alloy, titanium
, or zirconium
). Due to the nature of this process, producible geometries are very limited. They must be simple. Typical geometries produced include plates and tubing.
(which was developed in the early 19th century), explosion welding was developed relatively recently, in the decades after World War II
. Its origins, however, go back to World War I
, when it was observed that pieces of shrapnel
sticking to armor plating were not only embedding themselves, but were actually being welded to the metal. Since the extreme heat involved in other forms of welding did not play a role, it was concluded that the phenomenon was caused by the explosive forces acting on the shrapnel. These results were later duplicated in laboratory tests and, not long afterwards, the process was patented and put to use.
In 1962, DuPont
applied for a patent
on the explosion welding process, which was granted in 1964 and resulted in the use of the Detaclad trademark
to describe the process. On July 22, 1996, Dynamic Materials Corporation
completed the acquisition of DuPont's Detaclad operations for a purchase price of $5,321,850.
. Large areas can be bonded extremely quickly and the weld itself is very clean, due to the fact that the surface material of both metals is violently expelled during the reaction.
A major disadvantage of this method is that an expansive knowledge of explosives is needed before the procedure may be attempted. Explosion welding is therefore far less commonly used than fusion welding alternatives.
Process (science)
In science, a process is every sequence of changes of a real object/body which is observable using the scientific method. Therefore, all sciences analyze and model processes....
where welding
Welding
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes...
is accomplished by accelerating one of the components at extremely high velocity through the use of chemical explosives. This process is most commonly utilized to clad carbon steel plate with a thin layer of corrosion
Corrosion
Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen...
resistant material (e.g., stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
, nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
alloy, titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....
, or zirconium
Zirconium
Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium...
). Due to the nature of this process, producible geometries are very limited. They must be simple. Typical geometries produced include plates and tubing.
Development
Unlike other forms of welding such as arc weldingArc welding
Arc welding is a type of welding that uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point. They can use either direct or alternating current, and consumable or non-consumable electrodes...
(which was developed in the early 19th century), explosion welding was developed relatively recently, in the decades after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Its origins, however, go back to World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, when it was observed that pieces of shrapnel
Fragmentation (weaponry)
Fragmentation is the process by which the casing of an artillery shell, bomb, grenade, etc. is shattered by the detonating high explosive filling. The correct technical terminology for these casing pieces is fragments , although shards or splinters can be used for non-preformed fragments...
sticking to armor plating were not only embedding themselves, but were actually being welded to the metal. Since the extreme heat involved in other forms of welding did not play a role, it was concluded that the phenomenon was caused by the explosive forces acting on the shrapnel. These results were later duplicated in laboratory tests and, not long afterwards, the process was patented and put to use.
In 1962, DuPont
DuPont
E. I. du Pont de Nemours and Company , commonly referred to as DuPont, is an American chemical company that was founded in July 1802 as a gunpowder mill by Eleuthère Irénée du Pont. DuPont was the world's third largest chemical company based on market capitalization and ninth based on revenue in 2009...
applied for a patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
on the explosion welding process, which was granted in 1964 and resulted in the use of the Detaclad trademark
Trademark
A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...
to describe the process. On July 22, 1996, Dynamic Materials Corporation
Dynamic Materials Corporation
Dynamic Materials Corporation is a metalworking business.The company operates in two segments, explosive metalworking and aerospace. The explosive metalworking segment utilizes explosives to perform metal cladding and shock synthesis...
completed the acquisition of DuPont's Detaclad operations for a purchase price of $5,321,850.
Advantages and disadvantages
Explosion welding can produce a bond between two metals that cannot necessarily be welded by conventional means. The process does not melt either metal, instead it plasticizes the surfaces of both metals, causing them to come into intimate contact sufficient to create a weld. This is a similar principle to other non-fusion welding techniques, such as friction weldingFriction welding
Friction welding is a class of solid-state welding processes that generates heat through mechanical friction between a moving workpiece and a stationary component, with the addition of a lateral force called "upset" to plastically displace and fuse the materials...
. Large areas can be bonded extremely quickly and the weld itself is very clean, due to the fact that the surface material of both metals is violently expelled during the reaction.
A major disadvantage of this method is that an expansive knowledge of explosives is needed before the procedure may be attempted. Explosion welding is therefore far less commonly used than fusion welding alternatives.