Misplaced Pages

#631368

53-549: The Soul initially came in two colors: Platinum Silver and Soul Gray, later also coming in Pink, Silver, and Black and Gold. It is made of a metallic body and the slider has spring mechanism. There is a second, touch-sensitive OLED display below the main 2.2-inch display which shows different navigational functions, tailored for the current software operation (as previously appearing on the E950 model). Samsung dubs it as "Magical Touch". There

106-402: A linear function . Force of fully compressed spring where Zero-length spring is a term for a specially designed coil spring that would exert zero force if it had zero length. That is, in a line graph of the spring's force versus its length, the line passes through the origin. A real coil spring will not contract to zero length because at some point the coils touch each other. "Length" here

159-399: A torque proportional to the angle. A torsion spring's rate is in units of torque divided by angle, such as N·m / rad or ft·lbf /degree. The inverse of spring rate is compliance, that is: if a spring has a rate of 10 N/mm, it has a compliance of 0.1 mm/N. The stiffness (or rate) of springs in parallel is additive , as is the compliance of springs in series. Springs are made from

212-404: A change in ductility and hardness. As the material cools it recrystallizes. For many alloys, including carbon steel, the crystal grain size and phase composition, which ultimately determine the material properties, are dependent on the heating rate and cooling rate. Hot working or cold working after the annealing process alters the metal structure, so further heat treatments may be used to achieve

265-422: A lower yield strength and a lower tensile strength . This process is also called LP annealing for lamellar pearlite in the steel industry as opposed to a process anneal , which does not specify a microstructure and only has the goal of softening the material. Often the material to be machined is annealed, and then subject to further heat treatment to achieve the final desired properties. Short cycle annealing

318-431: A non-metallic spring is the bow , made traditionally of flexible yew wood, which when 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

371-453: A piece of inelastic material of the proper length so the zero force point would occur at zero length. A zero-length spring can be attached to a mass on a hinged boom in such a way that the force on the mass is almost exactly balanced by the vertical component of the force from the spring, whatever the position of the boom. This creates a horizontal pendulum with very long oscillation period . Long-period pendulums enable seismometers to sense

424-715: A proprietary Samsung connector. Despite its flagship status, the Samsung Soul does lack several key features like Wi-Fi, GPS , or smartphone software. These were instead implemented on the Samsung G810 , announced at the same time. The "Soul" name stands for "The Spirit of Ultra" (referring to Samsung Ultra Edition ). The U900 Soul name is an extension of the U900 FlipShot, a clamshell/swivel multimedia phone announced for Verizon Wireless in November 2007. Publisher S21 said that

477-411: A spring is the change in the force it exerts, divided by the change in deflection of the spring. That is, it is the gradient of the force versus deflection curve . An extension or compression spring's rate is expressed in units of force divided by distance, for example or N/m or lbf/in. A torsion spring is a spring that works by twisting; when it is twisted about its axis by an angle, it produces

530-562: A system can be determined through the spring constant k and its displacement x : U = ( 1 2 ) k x 2 {\displaystyle U=\left({\frac {1}{2}}\right)kx^{2}} The kinetic energy K of an object in simple harmonic motion can be found using the mass of the attached object m and the velocity at which the object oscillates v : K = ( 1 2 ) m v 2 {\displaystyle K=\left({\frac {1}{2}}\right)mv^{2}} Since there

583-444: A variable rate. However, a conical spring can be made to have a constant rate by creating the spring with a variable pitch. A larger pitch in the larger-diameter coils and a smaller pitch in the smaller-diameter coils forces the spring to collapse or extend all the coils at the same rate when deformed. Since force is equal to mass, m , times acceleration, a , the force equation for a spring obeying Hooke's law looks like: The mass of

SECTION 10

#1732884931632

636-481: A variety of elastic materials, the most common being spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after manufacture. Some non-ferrous metals are also used, including phosphor bronze and titanium for parts requiring corrosion resistance, and low- resistance beryllium copper for springs carrying electric current . Simple non-coiled springs have been used throughout human history, e.g.

689-441: Is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness , making it more workable. It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooling. In annealing, atoms migrate in the crystal lattice and the number of dislocations decreases, leading to

742-516: Is a stub . You can help Misplaced Pages by expanding it . Spring (device) A spring is a device consisting of an 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 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

795-464: Is a 5-megapixel camera with LED flash that can also take videos at 30 fps in QVGA (320x240) resolution. There is HSDPA support, and it is a "global" 3G phone supporting all major frequencies: GSM 850, GSM 900, GSM 1800, GSM 1900, HSDPA, UMTS 850, UMTS 1900, UMTS 2100. Audio playback makes use of a digital amplifier from Bang & Olufsen , although there is no 3.5 mm headphone jack, relying instead on

848-400: Is a heat treatment cycle that restores some of the ductility to a product being cold-worked so it can be cold-worked further without breaking. The temperature range for process annealing ranges from 260 °C (500 °F) to 760 °C (1400 °F), depending on the alloy in question. This process is mainly suited for low-carbon steel. The material is heated up to a temperature just below

901-565: Is also done in forming gas , a mixture of hydrogen and nitrogen. The magnetic properties of mu-metal (Espey cores) are introduced by annealing the alloy in a hydrogen atmosphere. Typically, large ovens are used for the annealing process. The inside of the oven is large enough to place the workpiece in a position to receive maximum exposure to the circulating heated air. For high volume process annealing, gas fired conveyor furnaces are often used. For large workpieces or high quantity parts, car-bottom furnaces are used so workers can easily move

954-502: Is appropriate only in the low-strain region. Hooke's law is a mathematical consequence of the fact that the potential energy of the rod is a minimum when it has its relaxed length. Any smooth function of one variable approximates a quadratic function when examined near enough to its minimum point as can be seen by examining the Taylor series . Therefore, the force – which is the derivative of energy with respect to displacement – approximates

1007-412: Is defined as the distance between the axes of the pivots at each end of the spring, regardless of any inelastic portion in-between. Zero-length springs are made by manufacturing a coil spring with built-in tension (A twist is introduced into the wire as it is coiled during manufacture; this works because a coiled spring unwinds as it stretches), so if it could contract further, the equilibrium point of

1060-454: Is found by taking the inverse of the period: f = 1 T = ω 2 π = 1 2 π k m {\displaystyle f={\frac {1}{T}}={\frac {\omega }{2\pi }}={\frac {1}{2\pi }}{\sqrt {\frac {k}{m}}}} In classical physics , a spring can be seen as a device that stores potential energy , specifically elastic potential energy , by straining

1113-459: Is no energy loss in such a system, energy is always conserved and thus: E = K + U {\displaystyle E=K+U} The angular frequency ω of an object in simple harmonic motion, given in radians per second, is found using the spring constant k and the mass of the oscillating object m : ω = k m {\displaystyle \omega ={\sqrt {\frac {k}{m}}}} The period T ,

SECTION 20

#1732884931632

1166-436: Is termed stress relief . The relief of internal stresses is a thermodynamically spontaneous process ; however, at room temperatures, it is a very slow process. The high temperatures at which annealing occurs serve to accelerate this process. The reaction that facilitates returning the cold-worked metal to its stress-free state has many reaction pathways, mostly involving the elimination of lattice vacancy gradients within

1219-419: Is to originate a uniform and stable microstructure that most closely resembles the metal's phase diagram equilibrium microstructure, thus letting the metal attain relatively low levels of hardness, yield strength and ultimate strength with high plasticity and toughness. To perform a full anneal on a steel for example, steel is heated to slightly above the austenitic temperature and held for sufficient time to allow

1272-408: Is used as a medium for quenching usually in the form of brine (salt water). Brine provides faster cooling rates than water. This is because when an object is quenched in water steam bubbles form on the surface of the object reducing the surface area the water is in contact with. The salt in the brine reduces the formation of steam bubbles on the object's surface, meaning there is a larger surface area of

1325-468: Is used for turning normal ferrite into malleable ferrite. It consists of heating, cooling and then heating again from 4 to 8 hours. Resistive heating can be used to efficiently anneal copper wire ; the heating system employs a controlled electrical short circuit . It can be advantageous because it does not require a temperature -regulated furnace like other methods of annealing. The process consists of two conductive pulleys ( step pulleys ), which

1378-425: The austenite transform into bainite or martensite , but rather have it completely transform to pearlite and ferrite or cementite . This means that steels that are very hardenable (i.e. tend to form martensite under moderately low cooling rates) have to be furnace cooled. The details of the process depend on the type of metal and the precise alloy involved. In any case the result is a more ductile material but

1431-510: The bow (and arrow). In the Bronze Age more sophisticated spring devices were used, as shown by the spread of tweezers in many cultures. Ctesibius of Alexandria developed a method for making springs out of an alloy of bronze with an increased proportion of tin, hardened by hammering after it was cast. Coiled springs appeared early in the 15th century, in door locks. The first spring powered-clocks appeared in that century and evolved into

1484-410: The amount of time for the spring-mass system to complete one full cycle, of such harmonic motion is given by: T = 2 π ω = 2 π m k {\displaystyle T={\frac {2\pi }{\omega }}=2\pi {\sqrt {\frac {m}{k}}}} The frequency f , the number of oscillations per unit time, of something in simple harmonic motion

1537-409: The appearance of new strain-free grains. The grain size and shape do not change. The second stage is recrystallization , where new strain-free grains nucleate and grow to replace those deformed by internal stresses. If annealing is allowed to continue once recrystallization has completed, then grain growth (the third stage) occurs. In grain growth, the microstructure starts to coarsen and may cause

1590-456: The body of the metal. The creation of lattice vacancies is governed by the Arrhenius equation , and the migration/diffusion of lattice vacancies are governed by Fick's laws of diffusion. In steel, there is a decarburization mechanism that can be described as three distinct events: the reaction at the steel surface, the interstitial diffusion of carbon atoms and the dissolution of carbides within

1643-417: The bonds between the atoms of an elastic material. Hooke's law of elasticity states that the extension of an elastic rod (its distended length minus its relaxed length) is linearly proportional to its tension , the force used to stretch it. Similarly, the contraction (negative extension) is proportional to the compression (negative tension). This law actually holds only approximately, and only when

Samsung SGH-U900 Soul - Misplaced Pages Continue

1696-518: The camera of the U900 Soul is "very good", but just below the "best" ones namely Nokia N95 and Sony Ericsson K850 . The review concluded calling it a "fabulous" phone. Wired called the touch-sensitive navigational pad "one of the coolest, most efficient" touch interfaces they have seen on a handset. TechRadar called the U900 Soul "extremely stylish with a quality camera", but criticized the battery life. This Samsung mobile phone-related article

1749-452: The crystal lattice, which allows these dopant atoms to function properly as dopants in the semiconducting material. Normalization is an annealing process applied to ferrous alloys to give the material a uniform fine-grained structure and to avoid excess softening in steel. It involves heating the steel to 20–50 °C above its upper critical point, soaking it for a short period at that temperature and then allowing it to cool in air. Heating

1802-446: The deformation (extension or contraction) is small compared to the rod's overall length. For deformations beyond the elastic limit , atomic bonds get broken or rearranged, and a spring may snap, buckle, or permanently deform. Many materials have no clearly defined elastic limit, and Hooke's law can not be meaningfully applied to these materials. Moreover, for the superelastic materials, the linear relationship between force and displacement

1855-404: The effect of redistributing and eradicating the dislocations in metals and (to a lesser extent) in ceramics. This alteration to existing dislocations allows a metal object to deform more easily, increasing its ductility. The amount of process-initiating Gibbs free energy in a deformed metal is also reduced by the annealing process. In practice and industry, this reduction of Gibbs free energy

1908-466: The first large watches by the 16th century. In 1676 British physicist Robert Hooke postulated Hooke's law , which states that the force a spring exerts is proportional to its extension. On March 8, 1850, John Evans, Founder of John Evans' Sons, Incorporated, opened his business in New Haven, Connecticut, manufacturing flat springs for carriages and other vehicles, as well as the machinery to manufacture

1961-515: The force with which the spring pushes back is linearly proportional to the distance from its equilibrium length: where Most real springs approximately follow Hooke's law if not stretched or compressed beyond their elastic limit . Coil springs and other common springs typically obey Hooke's law. There are useful springs that don't: springs based on beam bending can for example produce forces that vary nonlinearly with displacement. If made with constant pitch (wire thickness), conical springs have

2014-409: The initial displacement and velocity of the mass. The graph of this function with B = 0 {\displaystyle B=0} (zero initial position with some positive initial velocity) is displayed in the image on the right. In simple harmonic motion of a spring-mass system, energy will fluctuate between kinetic energy and potential energy , but the total energy of the system remains

2067-446: The lower critical temperature of steel. Cold-worked steel normally tends to possess increased hardness and decreased ductility, making it difficult to work. Process annealing tends to improve these characteristics. This is mainly carried out on cold-rolled steel like wire-drawn steel, centrifugally cast ductile iron pipe etc. A full annealing typically results in the second most ductile state a metal can assume for metal alloy. Its purpose

2120-424: The material to fully form austenite or austenite-cementite grain structure. The material is then allowed to cool very slowly so that the equilibrium microstructure is obtained. In most cases this means the material is allowed to furnace cool (the furnace is turned off and the steel is let cool down inside) but in some cases it is air cooled. The cooling rate of the steel has to be sufficiently slow so as to not let

2173-450: The metal is softened and prepared for further work such as shaping, stamping, or forming. Many other materials, including glass and plastic films , use annealing to improve the finished properties. Annealing occurs by the diffusion of atoms within a solid material, so that the material progresses towards its equilibrium state. Heat increases the rate of diffusion by providing the energy needed to break bonds. The movement of atoms has

Samsung SGH-U900 Soul - Misplaced Pages Continue

2226-405: The metal to lose a substantial part of its original strength. This can however be regained with hardening . The high temperature of annealing may result in oxidation of the metal's surface, resulting in scale. If scale must be avoided, annealing is carried out in a special atmosphere , such as with endothermic gas (a mixture of carbon monoxide , hydrogen gas , and nitrogen gas ). Annealing

2279-464: The object in contact with the water, thus facilitating better conduction of heat from the object to the surrounding water. Quench hardening is generally applicable to some ferrous alloys, but not copper alloys. In the semiconductor industry, silicon wafers are annealed to repair atomic level disorder from steps like ion implantation . In the process step, dopant atoms, usually boron , phosphorus or arsenic , move into substitutional positions in

2332-503: The parts in and out. Once the annealing process is successfully completed, workpieces are sometimes left in the oven so the parts cool in a controllable way. While some workpieces are left in the oven to cool in a controlled fashion, other materials and alloys are removed from the oven. Once removed from the oven, the workpieces are often quickly cooled off in a process known as quench hardening. Typical methods of quench hardening materials involve media such as air, water, oil, or salt. Salt

2385-499: The properties required. With knowledge of the composition and phase diagram , heat treatment can be used to adjust from harder and more brittle to softer and more ductile. In the case of ferrous metals , such as steel , annealing is performed by heating the material (generally until glowing) for a while and then slowly letting it cool to room temperature in still air. Copper , silver and brass can be either cooled slowly in air, or quickly by quenching in water. In this fashion,

2438-399: The same. A spring that obeys Hooke's Law with spring constant k will have a total system energy E of: E = ( 1 2 ) k A 2 {\displaystyle E=\left({\frac {1}{2}}\right)kA^{2}} Here, A is the amplitude of the wave-like motion that is produced by the oscillating behavior of the spring. The potential energy U of such

2491-423: The slowest waves from earthquakes. The LaCoste suspension with zero-length springs is also used in gravimeters because it is very sensitive to changes in gravity. Springs for closing doors are often made to have roughly zero length, so that they exert force even when the door is almost closed, so they can hold it closed firmly. Annealing (metallurgy) In metallurgy and materials science , annealing

2544-537: The spring is small in comparison to the mass of the attached mass and is ignored. Since acceleration is simply the second derivative of x with respect to time, This is a second order linear differential equation for the displacement x {\displaystyle x} as a function of time. Rearranging: the solution of which is the sum of a sine and cosine : A {\displaystyle A} and B {\displaystyle B} are arbitrary constants that may be found by considering

2597-406: The spring, the point at which its restoring force is zero, occurs at a length of zero. In practice, the manufacture of springs is typically not accurate enough to produce springs with tension consistent enough for applications that use zero length springs, so they are made by combining a negative length spring, made with even more tension so its equilibrium point would be at a negative length, with

2650-514: The springs. Evans was a Welsh blacksmith and springmaker who emigrated to the United States in 1847, John Evans' Sons became "America's oldest springmaker" which continues to operate today. Springs can be classified depending on how the load force is applied to them: They can also be classified based on their shape: The most common types of spring are: Other types include: An ideal spring acts in accordance with Hooke's law, which states that

2703-601: The steel just above its upper critical point creates austenitic grains (much smaller than the previous ferritic grains), which during cooling, form new ferritic grains with a further refined grain size. The process produces a tougher, more ductile material, and eliminates columnar grains and dendritic segregation that sometimes occurs during casting. Normalizing improves machinability of a component and provides dimensional stability if subjected to further heat treatment processes. Process annealing, also called intermediate annealing , subcritical annealing , or in-process annealing ,

SECTION 50

#1732884931632

2756-437: The steel. The three stages of the annealing process that proceed as the temperature of the material is increased are: recovery , recrystallization , and grain growth . The first stage is recovery , and it results in softening of the metal through removal of primarily linear defects called dislocations and the internal stresses they cause. Recovery occurs at the lower temperature stage of all annealing processes and before

2809-408: The wire passes across after it is drawn. The two pulleys have an electrical potential across them, which causes the wire to form a short circuit. The Joule effect causes the temperature of the wire to rise to approximately 400 °C. This temperature is affected by the rotational speed of the pulleys, the ambient temperature, and the voltage applied. Where t is the temperature of the wire, K

#631368