|
Explosive Forming
Explosive forming is a metalworking technique in which an explosive charge is used instead of a punch or press. It can be used on materials for which a press setup would be prohibitively large or require an unreasonably high pressure, and is generally much cheaper than building a large enough and sufficiently high-pressure press; on the other hand, it is unavoidably an individual job production process, producing one product at a time and with a long setup time. There are various approaches; one is to place metal plate over a die, with the intervening space evacuated by a vacuum pump, place the whole assembly underwater, and detonate a charge at an appropriate distance from the plate. For complicated shapes, a segmented die can be used to produce in a single operation a shape that would require many manufacturing steps, or to be manufactured in parts and welded together with an accompanying loss of strength at the welds. There is often some degree of work hardening from the explos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Job Production
Job production, sometimes called jobbing or one-off production, involves producing custom work, such as a one-off product for a specific customer or a small batch of work in quantities usually less than those of mass-market products. Job production consists of an operator or group of operators to work on a single job and complete it before proceeding to the next similar or different job. Together with batch production and mass production (flow production) it is one of the three main production methods. National Grid for Learning Cymru, retrieved: 2012-10-26. Job production can be classical by small firms (making railings for a specific house, building/re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Die (manufacturing)
A die is a specialized machine tool used in manufacturing industries to cut and/or form material to a desired shape or profile. Stamping dies are used with a press, as opposed to drawing dies (used in the manufacture of wire) and casting dies (used in molding) which are not. Like molds, dies are generally customized to the item they are used to create. Products made with dies range from simple paper clips to complex pieces used in advanced technology. Continuous-feed laser cutting may displace the analogous die-based process in the automotive industry, among others. Die stamping Blanking and piercing are two die cutting operations, and bending is an example of a die forming operation. Die forming Forming operations work by deforming materials like sheet metal or plastic using force (compression, tension, or both) and rely on the material's mechanical properties. Forming dies are typically made by tool and die makers and put into production after mounting into a press. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Work Hardening
In materials science, work hardening, also known as strain hardening, is the strengthening of a metal or polymer by plastic deformation. Work hardening may be desirable, undesirable, or inconsequential, depending on the context. This strengthening occurs because of dislocation movements and dislocation generation within the crystal structure of the material. Many non-brittle metals with a reasonably high melting point as well as several polymers can be strengthened in this fashion. Alloys not amenable to heat treatment, including low-carbon steel, are often work-hardened. Some materials cannot be work-hardened at low temperatures, such as indium, however others can be strengthened only via work hardening, such as pure copper and aluminum. Undesirable work hardening An example of undesirable work hardening is during machining when early passes of a cutter inadvertently work-harden the workpiece surface, causing damage to the cutter during the later passes. Certain alloys are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mild Steel
Carbon steel is a steel with carbon content from about 0.05 up to 2.1 percent by weight. The definition of carbon steel from the American Iron and Steel Institute (AISI) states: * no minimum content is specified or required for chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium, zirconium, or any other element to be added to obtain a desired alloying effect; * the specified minimum for copper does not exceed 0.40%; * or the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65%; silicon 0.60%; copper 0.60%. The term ''carbon steel'' may also be used in reference to steel which is not stainless steel; in this use carbon steel may include alloy steels. High carbon steel has many different uses such as milling machines, cutting tools (such as chisels) and high strength wires. These applications require a much finer microstructure, which improves the toughness. Carbon steel is a popular metal choic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yield Strength
In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, making the precise yield point difficult to determine. In such a case, the offset yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chine (aeronautics)
In aircraft design, a chine is a longitudinal line of sharp change in the cross-section profile of the fuselage or similar body. The term chine originates in boatbuilding, where it applies to a sharp profile change in the hull of a boat.Angled chine, different from soft (rounded) chine In a flying boat hull or floatplane float, the longitudinal line of sharp change in cross-section where the bottom plane meets the sidewall is an example of a chine. On some supersonic aircraft a chine extends sideways for some distance, with a very sharp edge blending in with the main wing leading edge root.NASA-AIAA-98-2725 ''Impact of fuselage cross-section on the stability of a generic fighter'' uses "chined-shaped fuselage cross section, chined forebody, fuselage with ... included chine angle" expressions. NASA CR 189641 and AIAA 2008-6228 use "Chine forebody and Chine fuselage" The rest of this article is concerned with this type of chine. Configuration A chine can in aerodynamic terms act ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SR-71
The Lockheed SR-71 "Blackbird" is a Range (aeronautics), long-range, high-altitude, Mach number, Mach 3+ military strategy, strategic reconnaissance aircraft developed and manufactured by the American aerospace company Lockheed Corporation. It was operated by the United States Air Force (USAF) and NASA. The SR-71 was developed as a black project from the Lockheed A-12 reconnaissance aircraft during the 1960s by Lockheed's Skunk Works division. American aerospace engineer Kelly Johnson (engineer), Clarence "Kelly" Johnson was responsible for many of the aircraft's innovative concepts. The shape of the SR-71 was based on that of the A-12, which was one of the first aircraft to be designed with a reduced radar cross-section. Initially, a strategic bomber, bomber variant of the A-12 was requested by Curtis LeMay, before the program was focused solely on reconnaissance. Mission equipment for the reconnaissance role included signals intelligence sensors, side looking airborne r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shaped Charge
A shaped charge is an explosive charge shaped to form an explosively formed penetrator (EFP) to focus the effect of the explosive's energy. Different types of shaped charges are used for various purposes such as cutting and forming metal, initiating nuclear weapons, penetrating armor, or perforating wells in the oil and gas industry. A typical modern shaped charge, with a metal liner on the charge cavity, can penetrate armor steel to a depth of seven or more times the diameter of the charge (charge diameters, CD), though greater depths of 10 CD and above have been achieved. Contrary to a misconception (possibly resulting from the acronym for ''high-explosive anti-tank'', HEAT) the shaped charge EFP jet does not depend in any way on heating or melting for its effectiveness; that is, the EFP jet from a shaped charge does not melt its way through armor, as its effect is purely kinetic in nature – however the process does create significant heat and often has a significant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Explosively Formed Projectiles
An explosively formed penetrator (EFP), also known as an explosively formed projectile (EFP), a self-forging warhead, or a self-forging fragment, is the product of a shaped charge designed to penetrate armor effectively. As the name suggests, the effect of the explosive charge is to deform a metal plate into a jet, slug or rod shape and accelerate it toward a target. They were first developed as oil well perforators by American oil companies in the 1930s, and were deployed as weapons in World War II. Difference from conventional shaped charges A shaped charge generally has a metal liner that is forced by an explosive blast into a metal jet or slug able to penetrate thick steel armor and knock out vehicles. A disadvantage of this arrangement is that the jet of metal loses effectiveness the further it travels, as it breaks up into disconnected particles that drift out of alignment. An EFP operates on the principle designed to form a distinct projectile (slug or jet), permitting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energy, digital industry, additive manufacturing and venture capital and finance, but has since divested from several areas, now primarily consisting of the first four segments. In 2020, GE ranked among the Fortune 500 as the 33rd largest firm in the United States by gross revenue. In 2011, GE ranked among the Fortune 20 as the 14th most profitable company, but later very severely underperformed the market (by about 75%) as its profitability collapsed. Two employees of GE – Irving Langmuir (1932) and Ivar Giaever (1973) – have been awarded the Nobel Prize. On November 9, 2021, the company announced it would divide itself into three investment-grade public companies. On July 18, 2022, GE unveiled the brand names of the companies it will ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplifier, amplification and current rectifier, rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
