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Coining (metalworking)
Coining is a form of precision stamping in which a workpiece is subjected to a sufficiently high stress to induce plastic flow on the surface of the material. A beneficial feature is that in some metals, the plastic flow reduces surface grain size, and work hardens the surface, while the material deeper in the part retains its toughness and ductility. The term comes from the initial use of the process: manufacturing of coins. Coining is used to manufacture parts for all industries and is commonly used when high relief or very fine features are required. For example, it is used to produce coins, badges, buttons, precision-energy springs and precision parts with small or polished surface features. Coining is a cold working process similar in other respects to forging, which takes place at elevated temperature; it uses a great deal of force to elastically deform a workpiece, so that it conforms to a die. Coining can be done using a gear driven press, a mechanical press, or m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coining Press(Royal Mint)
A coining press is a manually operated machine that mints coins from planchets. After centuries it was replaced by more modern machines. Presses came in multiple shapes and with different accessories (to collect the coins, etc.) They were made of cast iron. The basic elements are: * A triumphal arch with a built-in base * A vertically arranged leadscrew that supported an inertia wheel or more commonly, a piece made up of two radial arms with weights at the ends. * The leadscrew (male) rotates inside a threaded (female) nut. The nut is attached to the structure. The turn of the inertia wheel (or bar with weights) determines the rotation of the thread bar and its vertical displacement (up or down depending on the direction of rotation). * Vertical guides allow vertical displacement of the holder (upper die) without rotating. Operation Each coin is formed in a single operation. The press holds two ''negatives'' (molds that show each side of the coin) The body (material from whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spring (device)
A spring is a device consisting of an Elasticity (physics), elastic but largely rigid material (typically metal) bent or molded into a form (especially a coil) that can return into shape after being compressed or extended. Springs can Energy storage, store energy when compressed. In everyday use, the term most often refers to coil springs, but there are many different spring designs. Modern springs are typically manufactured from spring steel. An example of a non-metallic spring is the Bow (weapon), bow, made traditionally of flexible Taxus baccata, yew wood, which when Bow draw, drawn stores energy to propel an arrow. When a conventional spring, without stiffness variability features, is compressed or stretched from its resting position, it exerts an opposing force approximately proportional to its change in length (this approximation breaks down for larger deflections). The ''rate'' or ''spring constant'' of a spring is the change in the force it exerts, divided by the cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or interface (matter), surfaces to cling to one another. (Cohesion (chemistry), Cohesion refers to the tendency of similar or identical particles and surfaces to cling to one another.) The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work (physics), work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bonding Pad
Contact pads or bond pads are small, conductive surface areas of a printed circuit board (PCB) or die of an integrated circuit. They are often made of gold, copper, or aluminum and measure mere micrometres wide. Pads are positioned on the edges of die, to facilitate connections without shorting. Contact pads exist to provide a larger surface area for connections to a microchip or PCB, allowing for the input and output of data and power. Possible methods of connecting contact pads to a system include soldering, wirebonding, or flip chip mounting. Contact pads are created alongside a chip's functional structure during the photolithography steps of the fabrication process, and afterwards they are tested. During the test process, contact pads are probed with the needles of a probe card on Automatic Test Equipment Automatic test equipment or automated test equipment (ATE) is any apparatus that performs tests on a device, known as the device under test (DUT), equipment under te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Component
An electronic component is any basic discrete electronic device or physical entity part of an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components and elements. A datasheet for an electronic component is a technical document that provides detailed information about the component's specifications, characteristics, and performance. Discrete circuits are made of individual electronic components that only perform one function each as packaged, which are known as discrete components, although strictly the term discrete component refers to such a component with semiconductor material such as individual transistors. Electronic components have a number of electrical terminals or leads. These leads connect to other electrical components, often over wire, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soldering
Soldering (; ) is a process of joining two metal surfaces together using a filler metal called solder. The soldering process involves heating the surfaces to be joined and melting the solder, which is then allowed to cool and solidify, creating a strong and durable joint. Soldering is commonly used in the electronics industry for the manufacture and repair of Printed circuit board, printed circuit boards (PCBs) and other electronic components. It is also used in plumbing and Metalworking, metalwork, as well as in the manufacture of jewelry and other decorative items. The solder used in the process can vary in composition, with different alloys used for different applications. Common solder alloys include tin-lead, tin-silver, and tin-copper, among others. Lead-free solder has also become more widely used in recent years due to health and environmental concerns associated with the use of lead. In addition to the type of solder used, the temperature and method of heating also p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamping (metalworking)
Stamping (also known as pressing) is the process of placing flat sheet metal in either blank or coil form into a stamping press where a tool and Die (manufacturing), die surface forms the metal into a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, blanking, embossing, bending, flanging, and coining. This could be a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or could occur through a series of stages. The process is usually carried out on sheet metal, but can also be used on other materials, such as polystyrene. Progressive dies are commonly fed from a coil of steel, coil reel for unwinding of coil to a straightener to level the coil and then into a feeder which advances the material into the press and die at a predetermined feed length. Depending on part complexity, the number of stations in the die can be determined. St ... [...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 Forming (metalworking), form material to a desired shape or profile. ''Stamping (metalworking), Stamping dies'' are used with a machine press, press, as opposed to ''Draw plate, drawing dies'' (used in the manufacture of wire) and ''Die casting, casting dies'' (used in Molding (process), 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 production, Continuous-feed laser cutting may displace the analogous die-based process in the automotive industry, among others. Die stamping Blanking and piercing are two Shearing (manufacturing), die cutting operations, and Bending (metalworking), bending is an example of a die forming operation. Die forming Forming operations work by deforming materials like sheet metal or plastic using force (Compre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forging
Forging is a manufacturing process involving the shaping of metal using localized compression (physics), compressive forces. The blows are delivered with a hammer (often a power hammer) or a die (manufacturing), die. Forging is often classified according to the temperature at which it is performed: cold forging (a type of cold working), warm forging, or hot forging (a type of hot working). For the latter two, the metal is heated, usually in a forge. Forged parts can range in weight from less than a kilogram to hundreds of metric tons.Degarmo, p. 389 Forging has been done by metalsmith, smiths for millennia; the traditional products were kitchenware, household hardware, hardware, hand tools, edged weapons, cymbals, and jewellery. Since the Industrial Revolution, forged parts are widely used in mechanism (engineering), mechanisms and machines wherever a component requires high strength of materials, strength; such forgings usually require further processing (such as machining) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold Working
In metallurgy, cold forming or cold working is any metalworking process in which metal is shaped below its recrystallization temperature, usually at the ambient temperature at or near room temperature. Such processes are contrasted with hot working techniques like hot rolling, forging, welding, etc. The same or similar terms are used in glassmaking for the equivalents; for example cut glass is made by "cold work", cutting or grinding a formed object. Cold forming techniques are usually classified into four major groups: squeezing, bending, drawing, and shearing. They generally have the advantage of being simpler to carry out than hot working techniques. Unlike hot working, cold working causes the crystal grains and inclusions to distort following the flow of the metal; which may cause work hardening and anisotropic material properties. Work hardening makes the metal harder, stiffer, and stronger, but less plastic, and may cause cracks of the piece. The possible us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buttons
A button is a fastener that joins two pieces of fabric together by slipping through a loop or by sliding through a buttonhole. In modern clothing and fashion design, buttons are commonly made of plastic but also may be made of metal, wood, or seashell. Buttons can also be used on containers such as wallets and bags. Buttons may be sewn onto garments and similar items exclusively for purposes of ornamentation. In the applied arts and craft, a button can be an example of folk art, studio craft, or even a miniature work of art. In archaeology, a button can be a significant artifact. History Buttons and button-like objects used as ornaments or seals rather than fasteners have been discovered in the Indus Valley civilization during its Kot Diji phase (c. 2800–2600 BC). Buttons as apparel have been found at sites of the Catacomb culture, Russia (2500-1950 BC), at the Tomb of the Eagles, Scotland (2200–1800 BC), and at Bronze Age sites in China (c. 2000–1500 BC) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
