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Chobham Armour
Chobham armour is the informal name of a composite armour developed in the 1960s at the Military Vehicles and Engineering Establishment, a British tank research centre on Chobham Lane in Chertsey. The name has since become the common generic term for composite ceramic vehicle armour. Other names informally given to Chobham armour include ''Burlington'' and ''Dorchester''. ''Special armour'' is a broader informal term referring to any armour arrangement comprising ''sandwich'' reactive plates, including Chobham armour. Within the Ministry of Defence (MoD), ''Chobham'' usually refers specifically to the non-explosive reactive armor & ceramic composites, while ''Dorchester'' is usually in reference to additional armour packages, primarily composed of explosive reactive armour and spaced armour, although these are often conflated when in colloquial usage. Although the construction details of the Chobham armour remain a secret, it has been described as being composed of ceram ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardness
In materials science, hardness (antonym: softness) is a measure of the resistance to plastic deformation, such as an indentation (over an area) or a scratch (linear), induced mechanically either by Pressing (metalworking), pressing or abrasion (mechanical), abrasion. In general, different materials differ in their hardness; for example hard metals such as titanium and beryllium are harder than soft metals such as sodium and metallic tin, or wood and common plastics. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elasticity (physics), elastic stiffness, plasticity (physics), plasticity, deformation (mechanics), strain, strength of materials, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virtuous Circle And Vicious Circle
A vicious circle (or cycle) is a complex chain of events that reinforces itself through a feedback loop, with detrimental results. It is a system with no tendency toward equilibrium (social, economic, ecological, etc.), at least in the short run. Each iteration of the cycle reinforces the previous one, in an example of positive feedback. A vicious circle will continue in the direction of its momentum until an external factor intervenes to break the cycle. A well-known example of a vicious circle in economics is hyperinflation. When the results are not detrimental but beneficial, the term virtuous cycle is used instead. Examples Subprime mortgage crisis The contemporary subprime mortgage crisis is a complex group of vicious circles, both in its genesis and in its manifold outcomes, most notably the late 2000s recession. A specific example is the circle related to housing. As housing prices decline, more homeowners go " underwater", when the market value of a home drop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brittle
A material is brittle if, when subjected to stress, it fractures with little elastic deformation and without significant plastic deformation. Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a sharp snapping sound. When used in materials science, it is generally applied to materials that fail when there is little or no plastic deformation before failure. One proof is to match the broken halves, which should fit exactly since no plastic deformation has occurred. Brittleness in different materials Polymers Mechanical characteristics of polymers can be sensitive to temperature changes near room temperatures. For example, poly(methyl methacrylate) is extremely brittle at temperature 4˚C, but experiences increased ductility with increased temperature. Amorphous polymers are polymers that can behave differently at different temperatures. They may behave like a glass at low temperatures (the gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abrasion (mechanical)
Abrasion is the process of scuffing, scratching, wearing down, marring, or rubbing away. It can be intentionally imposed in a controlled process using an abrasive. Abrasion can be an undesirable effect of exposure to normal use or exposure to the elements. In stone shaping Ancient artists, working in stone, used abrasion to create sculptures. The artist selected dense stones like carbonite and emery and rubbed them consistently against comparatively softer stones like limestone and granite. The artist used different sizes and shapes of abrasives, or turned them in various ways as they rubbed, to create effects on the softer stone's surface. Water was continuously poured over the surface to carry away particles. Abrasive technique in stone shaping was a long, tedious process that, with patience, resulted in eternal works of art in stone. Models The Archard equation is a simple model used to describe sliding wear and is based on the theory of asperity (materials science), asperit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 battlefield mobility provided by tracks and a powerful engine; their main armament is often mounted within a turret. They are a mainstay of modern 20th and 21st century ground forces and a key part of combined arms combat. Modern tanks are versatile mobile land weapons platforms whose main armament is a large- calibre tank gun mounted in a rotating gun turret, supplemented by machine guns or other ranged weapons such as anti-tank guided missiles or rocket launchers. They have heavy vehicle armour which provides protection for the crew, the vehicle's munition storage, fuel tank and propulsion systems. The use of tracks rather than wheels provides improved operational mobility which allows the tank to overcome rugged terrain and adverse conditions such as mud and ice/snow better than wheele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K1 88-Tank
The K1, sometimes referred to as the 88 Tank (88 전차), is a South Korean main battle tank designed by Chrysler Defense (later General Dynamics Land Systems) and Hyundai Precision Industry (later Hyundai Rotem) for the Republic of Korea Armed Forces. It is a derivative of Chrysler, Chrysler's M1 Abrams, tailored to meet the ROK's unique requirements. The K1A1 is an upgraded variant based on the GDLS technical data package with a Rheinmetall Rh-120, 120 mm 44 caliber smoothbore gun, and is outfitted with more modern electronics, ballistic computers, fire control systems, and armor. Hyundai Rotem produced 1,511 K1 and K1A1 tanks between 1986 and 2011. Development In the early 1970s, South Korea received an intelligence report about North Korea locally producing Soviet T-62 tanks. Meanwhile, the U.S. 7th Infantry Division (United States), 7th Infantry Division began withdrawing from South Korea from 1969 to 1971 under the Nixon Doctrine. South Korean President Park Chung ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Challenger 2
The FV4034 Challenger 2 (MoD designation "CR2") is a third generation British main battle tank (MBT) in service with the armies of the United Kingdom, Oman, and Ukraine. It was designed by Vickers Defence Systems (now Rheinmetall BAE Systems Land (RBSL)) as a private venture in 1986, and was an extensive redesign of the company's earlier Challenger 1 tank. The Ministry of Defence ordered a prototype in December 1988. The Challenger 2 has four crew members consisting of a commander, gunner, loader, and driver. The main armament is a L30A1 rifled tank gun, an improved derivative of the L11 gun used on the Chieftain and Challenger 1. Fifty rounds of ammunition are carried for the main armament, alongside 4,200 rounds of 7.62 mm ammunition for the tank's secondary weapons: a L94A1 EX-34 chain gun mounted coaxially, and a L37A2 (GPMG) machine gun. The turret and hull are protected with second generation Chobham armour, also known as Dorchester. Powered by a Perkins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Challenger 1
The FV4030/4 Challenger 1 is a British main battle tank (MBT) used by the British Army from 1983 to 2001, when it was superseded by the Challenger 2. The majority of the Challenger 1 fleet was subsequently sold to Jordan where it remained in service with the Royal Jordanian Army until withdrawals were announced in 2018. Known locally as ''Al-Hussein'', these vehicles received various Jordanian modifications before being replaced by French-made Leclerc tanks from the UAE and ex-Italian Centauro 8x8 wheeled tank destroyers. The Jordanian Challenger 1 fleet had been retired by January 2023. History The Challenger design by the former Military Vehicles and Engineering Establishment (MVEE) near Chobham in Surrey originated in an Iranian order for an improved version of the Chieftain line of tanks in service around the world. These were the Chieftain Mk5(P)- FV4030/1, FV4030/2 Shir (Lion) 1 and 4030/3 Shir 2. With the fall of the Shah of Iran and the collapse of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M1 Abrams
The M1 Abrams () is a third-generation American main battle tank designed by Chrysler Defense (now General Dynamics Land Systems) and named for General Creighton Abrams. Conceived for modern armored ground warfare, it is one of the heaviest tanks in service at nearly . It introduced several modern technologies to the United States armored forces, including a multifuel turbine engine, sophisticated Chobham composite armor, a computer fire control system, separate ammunition storage in a blowout compartment, and NBC protection for crew safety. Initial models of the M1 were armed with a 105 mm M68 gun, while later variants feature a license-produced Rheinmetall 120 mm L/44 designated M256. The M1 Abrams was developed from the failed joint American- West German MBT-70 project that intended to replace the dated M60 tank. There are three main operational Abrams versions: the M1, M1A1, and M1A2, with each new iteration seeing improvements in armament, protecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chieftain (tank)
The FV4201 Chieftain was the primary main battle tank (MBT) of the United Kingdom from the 1960s into 1990s. Introduced in 1967, it was among the most heavily armed MBTs at the time, mounting a 120 mm Royal Ordnance L11 gun, equivalent to the much larger specialist heavy tanks in service. It was also among the most heavily armoured, with up to that was highly sloped to offer thickness along the line of sight. A development from the Centurion MBT, the Chieftain introduced the supine (reclining) driver position to British design allowing a heavily sloped hull with reduced height. A new powerpack and improved transmission gave it higher speed than the Centurion despite being heavier due to major upgrades to armour protection and the armament; this allowed it to replace both the Centurion and Conqueror heavy tank while performing their roles effectively. The multi-fuel engine proved to be the design's primary drawback leading to break downs; it was said that the Chieftain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetic Energy Penetrator
A kinetic energy penetrator (KEP), also known as long-rod penetrator (LRP), is a type of ammunition designed to penetrate vehicle armour using a flechette-like, high- sectional density projectile. Like a bullet or kinetic energy weapon, this type of ammunition does not contain explosive payloads and uses purely kinetic energy to penetrate the target. Modern KEP munitions are typically of the armour-piercing fin-stabilized discarding sabot (APFSDS) type. History Early cannons fired kinetic energy ammunition, initially consisting of heavy balls of worked stone and later of dense metals. From the beginning, combining high muzzle energy with projectile weight and hardness have been the foremost factors in the design of such weapons. Similarly, the foremost purpose of such weapons has generally been to defeat protective shells of armored vehicles or other defensive structures, whether it is stone walls, sailship timbers, or modern tank armour. Kinetic energy ammunition, in its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
