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High-Frequency Impact Treatment
The high-frequency impact treatment or HiFIT – Method is the treatment of welded steel constructions at the weld transition to increase the fatigue strength. Features The durability and life of dynamically loaded, welded steel structures is determined in many cases by the welds, in particular the weld transitions. Through selective treatment of the transitions (grinding (abrasive cutting), abrasive blasting, hammering, etc.), the durability of many designs increase significantly. Hammering methods have proven to be particularly effective treatment methods and were within the joint project REFRESH extensively studied and developed. The HiFIT (High-Frequency Impact Treatment (also called HFMI (High Frequency Mechanical Impact))) process is such a hammering method that is universally applicable, requires only a low tech equipment and still offers high reproducibility and the possibility for quality control. Operation The HiFIT hammer operates with a hardened pin with a ball ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Example HiFIT-treated Assembly
Example may refer to: * ''exempli gratia'' (e.g.), usually read out in English as "for example" * .example, reserved as a domain name that may not be installed as a top-level domain of the Internet ** example.com, example.net, example.org, and example.edu: second-level domain names reserved for use in documentation as examples * HMS ''Example'' (P165), an Archer-class patrol and training vessel of the Royal Navy Arts * ''The Example'', a 1634 play by James Shirley * ''The Example'' (comics), a 2009 graphic novel by Tom Taylor and Colin Wilson * Example (musician), the British dance musician Elliot John Gleave (born 1982) * ''Example'' (album), a 1995 album by American rock band For Squirrels See also * Exemplar (other), a prototype or model which others can use to understand a topic better * Exemplum, medieval collections of short stories to be told in sermons * Eixample The Eixample (, ) is a district of Barcelona between the old city (Ciutat Vella) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welding
Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Common alternative methods include solvent welding (of thermoplastics) using chemicals to melt materials being bonded without heat, and #Solid-state welding, solid-state welding processes which bond without melting, such as pressure, cold welding, and diffusion bonding. Metal welding is distinct from lower temperature bonding techniques such as brazing and soldering, which do not melt the base metal (parent metal) and instead require flowing a filler metal to solidify their bonds. In addition to melting the base metal in welding, a filler material is typically added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that can be stronger than the base material. Welding also requires a form of shield to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Tools
A power tool is a tool that is actuated by an additional power source and mechanism other than the solely manual labor used with hand tools. The most common types of power tools use electric motors. Internal combustion engines and compressed air are also commonly used. Tools directly driven by animal power are not generally considered power tools. Power tools can produce large amounts of particulates, including ultrafine particles. Airborne particulate matter is a Group 1 carcinogen. Uses Power tools are used in industry, in construction, in renovation, in the garden, for housework tasks such as cooking, cleaning, and around the house for purposes of driving (fasteners), drilling, cutting, shaping, sanding, grinding, routing, polishing, painting, metalworking, woodworking, heating and more. Using hand and power tools to cut plastic materials during construction activities can generate microplastics. Airborne microplastics is a type of particulates. Further studies are need ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hand-held Power Tools
A mobile device or handheld device is a computer small enough to hold and operate in hand. Mobile devices are typically battery-powered and possess a flat-panel display and one or more built-in input devices, such as a touchscreen or keypad. Modern mobile devices often emphasize wireless networking, to both the Internet and to other devices in their vicinity, such as headsets or in-car entertainment systems, via Wi-Fi, Bluetooth, cellular networks, or near-field communication. Characteristics Device mobility can be viewed in the context of several qualities: * Physical dimensions and weight * Whether the device is mobile or some kind of host to which it is attached is mobile * What kind of host devices it can be bound with * How devices communicate with a host * When mobility occurs Strictly speaking, many so-called mobile devices are not mobile. It is the host that is mobile, i.e., a mobile human host carries a non-mobile smartphone device. An example of a true mobile computing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatic Tools
A pneumatic tool, air tool, air-powered tool or pneumatic-powered tool is a type of power tool, driven by compressed air supplied by an air compressor. Pneumatic tools can also be driven by compressed carbon dioxide () stored in small cylinders allowing for portability. Most pneumatic tools convert the compressed air to work using a pneumatic motor. Compared to electric power tool equivalents, pneumatic tools are safer to run and maintain, without risk of sparks, short-circuiting or electrocution, and have a higher power to weight ratio, allowing a smaller, lighter tool to accomplish the same task. Furthermore, they are less likely to self-destruct in case the tool is jammed or overloaded. General grade pneumatic tools with a short life span are commonly less expensive and considered “disposable tools” in tooling industries, while industrial grade pneumatic tools with long life span are more expensive. In general, pneumatic tools are cheaper than the equivalent electric-powere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autofrettage
Autofrettage is a work-hardening process in which a pressure vessel (thick walled) is subjected to enormous pressure, causing internal portions of the part to plastic yield, yield plastically, resulting in internal compressive residual stresses once the pressure is released. The goal of autofrettage is to increase the pressure-carrying capacity of the final product. Inducing residual compressive stresses into materials can also increase their resistance to stress corrosion cracking; that is, non-mechanically assisted cracking that occurs when a material is placed in a corrosive environment in the presence of tensile stress. The technique is commonly used in manufacture of high-pressure pump cylinders, warship and gun barrels, and fuel injection systems for diesel engines. Due to work-hardening process it also enhances wear life of the barrel marginally. While autofrettage will induce some work hardening, that is not the primary mechanism of strengthening. The start point is a si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shot Peening
Shot peening is a cold working process used to produce a compressive residual stress layer and modify the mechanical properties of metals and composites. It entails striking a surface with shot (round metallic, glass, or ceramic particles) with force sufficient to create plastic deformation."Shot Peening," ''Tool and Manufacturing Engineers Handbook'' (TMEH), Volume 3, Society of Manufacturing Engineers, 1985 In machining, shot peening is used to strengthen and relieve stress in components like steel automobile crankshafts and connecting rods. In architecture it provides a muted finish to metal. Shot peening is similar mechanically to sandblasting, though its purpose is not to remove material, but rather it employs the mechanism of plasticity to achieve its goal, with each particle functioning as a ball-peen hammer. Details Peening a surface spreads it plastically, causing changes in the mechanical properties of the surface. Its main application is to avoid the propagation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Impact Treatment
Ultrasonic impact treatment (UIT) is a metallurgical processing technique, similar to work hardening, in which ultrasonic energy is applied to a metal object. This technique is part of the High Frequency Mechanical Impact (HFMI) processes. Other acronyms are also equivalent: Ultrasonic Needle Peening (UNP), Ultrasonic Peening (UP). Ultrasonic impact treatment can result in controlled residual compressive stress, grain refinement and grain size reduction. Low and high cycle fatigue are enhanced and have been documented to provide increases up to ten times greater than non-UIT specimens. Theory In UIT, ultrasonic waves are produced by an electro-mechanical ultrasonic transducer, and applied to a workpiece. An acoustically tuned resonator bar is caused to vibrate by energizing it with a magnetostrictive or Piezoelectric ultrasonic transducer. The energy generated from these high frequency impulses is imparted to the treated surface through the contact of specially designed s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandblasting
Sandblasting, sometimes known as abrasive blasting, is the operation of forcibly propelling a stream of abrasive material against a surface under high pressure to smooth a rough surface, roughen a smooth surface, shape a surface or remove surface contaminants. A pressurised fluid, typically compressed air, or a centrifugal wheel is used to propel the blasting material (often called the ''media''). The first abrasive blasting process was patented by Benjamin Chew Tilghman on 18 October 1870. There are several variants of the process, using various media; some are highly abrasive, whereas others are milder. The most abrasive are shot blasting (with metal shot) and sandblasting (with sand). Moderately abrasive variants include glass bead blasting (with glass beads) and plastic media blasting (PMB) with ground-up plastic stock or walnut shells and corncobs. Some of these substances can cause anaphylactic shock to individuals allergic to the media. A mild version is sodablas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welding
Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Common alternative methods include solvent welding (of thermoplastics) using chemicals to melt materials being bonded without heat, and #Solid-state welding, solid-state welding processes which bond without melting, such as pressure, cold welding, and diffusion bonding. Metal welding is distinct from lower temperature bonding techniques such as brazing and soldering, which do not melt the base metal (parent metal) and instead require flowing a filler metal to solidify their bonds. In addition to melting the base metal in welding, a filler material is typically added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that can be stronger than the base material. Welding also requires a form of shield to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Finishing
Surface finishing is a broad range of industrial processes that alter the surface of a manufactured item to achieve a certain property. Finishing processes may be employed to: improve product appearance, adhesion or wettability, solderability, corrosion resistance, tarnish resistance, the chemical resistance, the wear resistance, hardness, modify electrical conductivity, remove burrs and other surface flaws, and control the surface friction.. In limited cases some of these techniques can be used to restore original dimensions to salvage or repair an item. An unfinished surface is often called '' mill finish''. These processes can improve the durability, performance and even the appearance of the surface being finished. Surface finishing is often one of the final steps taken when working metal and is essential for guaranteeing that metal components meet the requirements of the necessary finish. Surface finishing processes can be categorized by how they affect the workpiece: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Residual Stress
In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones. However, unintended residual stress in a designed structure may cause it to fail prematurely. Residual stresses can result from a variety of mechanisms including inelastic (plastic) deformations, temperature gradients (during thermal cycle) or structural changes ( phase transformation). Heat from welding may cause localized expansion, which is taken up during welding by either the molten metal or the placement of parts being welded. When the finished weldment cools, some areas cool and contract more than others ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
