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| {{About|deformation in engineering|a more rigorous treatment|Deformation (mechanics)}}
| | Are you constantly having problems with the PC? Are you always searching for techniques to increase PC performance? Next this is the post you're searching for. Here we'll discuss a few of the many asked issues with regards to having you PC serve you well; how could I make my computer quicker for free? How to create my computer run faster?<br><br>We all learn that the registry is the important component of the Windows running program because it stores all information regarding the Dll files, programs found on the computer plus program settings. However, because days by, it happens to be unavoidable which we might encounter registry issue due to a huge amount of invalid, useless and unwelcome entries.<br><br>Windows is surprisingly dumb. It only knows how to follow commands plus instructions, that means that when we install a system, which program has to tell Windows precisely what to do. This really is done by storing an "training file" inside the registry of the system. All a computer programs place these "manuals" into the registry, permitting a computer to run a broad array of programs. When you load up 1 of those programs, Windows merely looks up the system file in the registry, and carries out its instructions.<br><br>Always see with it that we have installed antivirus, anti-spyware and anti-adware programs and have them updated on a regular basis. This can help stop windows XP running slow.<br><br>Google Chrome crashes on Windows 7 if the registry entries are improperly modified. Missing registry keys or registry keys with improper values can cause runtime mistakes plus thereby the issue occurs. We are suggested to scan the entire system registry and review the outcome. Attempt the registry repair procedure using third-party [http://bestregistrycleanerfix.com windows registry cleaner] software.<br><br>S/w connected error handling - If the blue screen bodily memory dump happens following the installation of s/w application or a driver it might be that there is program incompatibility. By booting into secure mode plus removing the software you are able to promptly fix this error. We might additionally try out a "program restore" to revert to an earlier state.<br><br>When the registry is corrupt or full of mistakes, the signs may be felt by the computer owner. The slow performance, the frequent program crashes plus the nightmare of all computer owners, the blue screen of death.<br><br>There is a lot a good registry cleaner will do for your computer. It may check for plus download changes for Windows, Java and Adobe. Keeping changes present is an important piece of advantageous computer wellness. It will furthermore protect the personal and business confidentiality and your online safety. |
| {{Refimprove|date=September 2008}}
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| [[Image:DeformationDueToCompression.png|thumb|right|58px|Compressive stress results in deformation which shortens the object but also expands it outwards.]]
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| In [[materials science]], '''deformation''' is a change in the shape or size of an object due to
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| * an applied [[force (physics)|force]] (the deformation energy in this case is transferred through work) or
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| * a change in temperature (the deformation energy in this case is transferred through heat).
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| The first case can be a result of [[tensile strength|tensile]] (pulling) forces, [[compressive strength|compressive]] (pushing) forces, [[Simple shear|shear]], [[bending]] or [[Torsion (mechanics)|torsion]] (twisting).
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| In the second case, the most significant factor, which is determined by the temperature, is the mobility of the structural defects such as grain boundaries, point vacancies, line and screw dislocations, stacking faults and twins in both crystalline and non-crystalline solids. The movement or displacement of such mobile defects is thermally activated, and thus limited by the rate of atomic diffusion. <ref name="Dav">Davidge, R.W., '''Mechanical Behavior of Ceramics''', Cambridge Solid State Science Series, Eds. Clarke, D.R., et al. (1979)</ref><ref name="Zar">Zarzycki, J., '''Glasses and the Vitreous State''', Cambridge Solid State Science Series, Eds. Clarke, D.R., et al.(1991)</ref>
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| Deformation is often described as [[strain (materials science)|strain]].
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| As deformation occurs, internal inter-molecular forces arise that oppose the applied force. If the applied force is not too large these forces may be sufficient to completely resist the applied force, allowing the object to assume a new equilibrium state and to return to its original state when the load is removed. A larger applied force may lead to a permanent deformation of the object or even to its [[structural failure]].
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| In the figure it can be seen that the compressive loading (indicated by the arrow) has caused deformation in the [[cylinder (geometry)|cylinder]] so that the original shape (dashed lines) has changed (deformed) into one with bulging sides. The sides bulge because the material, although strong enough to not crack or otherwise fail, is not strong enough to support the load without change, thus the material is forced out laterally. Internal forces (in this case at right angles to the deformation) resist the applied load.
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| The concept of a [[rigid body]] can be applied if the deformation is negligible.
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| ==Types of deformation==
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| Depending on the type of material, size and geometry of the object, and the forces applied, various types of deformation may result. The image to the right shows the engineering stress vs. strain diagram for a typical ductile material such as steel. Different deformation modes may occur under different conditions, as can be depicted using a [[deformation mechanism map]].
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| [[Image:Stress Strain Ductile Material.png|thumb|right|450px|Typical stress vs. strain diagram with the various stages of deformation.]]
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| ===Elastic deformation===
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| {{more|Elasticity (physics)}}
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| This type of deformation is reversible. Once the forces are no longer applied, the object returns to its original shape. [[Elastomer]]s and [[shape memory]] metals such as [[Nitinol]] exhibit large elastic deformation ranges, as does [[rubber]]. However elasticity is nonlinear in these materials. Normal metals, ceramics and most crystals show linear elasticity and a smaller elastic range.
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| Linear elastic deformation is governed by [[Hooke's law]], which states:
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| :<math>\sigma = E \varepsilon</math>
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| Where <math>\sigma</math> is the applied [[stress (physics)|stress]], <math>E</math> is a material constant called [[Young's modulus]], and ε is the resulting [[strain (materials science)|strain]]. This relationship only applies in the elastic range and indicates that the slope of the stress vs. strain curve can be used to find Young's modulus. Engineers often use this calculation in tensile tests. The [[linear elasticity|elastic range]] ends when the material reaches its [[yield stress|yield strength]]. At this point plastic deformation begins.
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| Note that not all elastic materials undergo linear elastic deformation; some, such as concrete, gray cast iron, and many polymers, respond nonlinearly. For these materials Hooke's law is inapplicable.<ref>Fundamentals of Materials Science and Engineering, William D. Callister, John Wiley and Sons, 2nd International edition (September 3, 2004), ISBN 0-471-66081-7, ISBN 978-0-471-66081-1, p.184</ref>
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| ===Plastic deformation===
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| {{See also|Plasticity (physics)}}
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| This type of deformation is irreversible. However, an object in the plastic deformation range will first have undergone elastic deformation, which is reversible, so the object will return part way to its original shape. Soft [[thermoplastics]] have a rather large plastic deformation range as do ductile metals such as [[copper]], [[silver]], and [[gold]]. [[Steel]] does, too, but not [[cast iron]]. Hard thermosetting plastics, rubber, crystals, and ceramics have minimal plastic deformation ranges. One material with a large plastic deformation range is wet [[chewing gum]], which can be stretched dozens of times its original length.
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| Under tensile stress, plastic deformation is characterized by a [[strain hardening]] region and a [[necking (engineering)|necking]] region and finally, fracture (also called rupture). During strain hardening the material becomes stronger through the movement of [[dislocation|atomic dislocations]]. The necking phase is indicated by a reduction in cross-sectional area of the specimen. Necking begins after the ultimate strength is reached. During necking, the material can no longer withstand the maximum stress and the strain in the specimen rapidly increases. Plastic deformation ends with the fracture of the material.
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| ====Metal fatigue====
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| Another deformation mechanism is [[metal fatigue]], which occurs primarily in [[ductile]] metals. It was originally thought that a material deformed only within the elastic range returned completely to its original state once the forces were removed. However, faults are introduced at the molecular level with each deformation. After many deformations, cracks will begin to appear, followed soon after by a fracture, with no apparent plastic deformation in between. Depending on the material, shape, and how close to the elastic limit it is deformed, failure may require thousands, millions, billions, or trillions of deformations.
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| Metal fatigue has been a major cause of aircraft failure, such as the [[De Havilland Comet#Accidents and incidents|De Havilland Comet accidents]], especially before the process was well understood. There are two ways to determine when a part is in danger of metal fatigue; either predict when failure will occur due to the material/force/shape/iteration combination, and replace the vulnerable materials before this occurs, or perform inspections to detect the microscopic cracks and perform replacement once they occur. Selection of materials not likely to suffer from metal fatigue during the life of the product is the best solution, but not always possible. Avoiding shapes with sharp corners limits metal fatigue by reducing stress concentrations, but does not eliminate it.
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| ====Compressive failure====
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| Usually, compressive stress applied to bars, [[column]]s, etc. leads to shortening.
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| Loading a structural element or specimen will increase the compressive stress until it reaches its [[compressive strength]]. According to the properties of the material, failure modes are [[Yielding (engineering)|yielding]] for materials with [[ductile]] behavior (most [[metal]]s, some [[soil]]s and [[plastic]]s) or rupturing for brittle behavior (geomaterials, [[cast iron]], [[glass]], etc.).
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| In long, slender structural elements — such as columns or [[truss]] bars — an increase of compressive force ''F'' leads to [[structural failure]] due to [[buckling]] at lower stress than the compressive strength.
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| ===Fracture===
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| [[Image:stress-strain1.svg|thumb|right|300px|Diagram of a [[stress-strain curve]], showing the relationship between stress (force applied) and strain (deformation) of a ductile metal.]]
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| {{See also|Fracture mechanics}}
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| {{See also|Concrete fracture analysis}}
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| This type of deformation is also irreversible. A break occurs after the material has reached the end of the elastic, and then plastic, deformation ranges. At this point forces accumulate until they are sufficient to cause a fracture. All materials will eventually fracture, if sufficient forces are applied.
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| ==Misconceptions==
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| A popular misconception is that all materials that bend are "weak" and those that don't are "strong." In reality, many materials that undergo large elastic and plastic deformations, such as steel, are able to absorb stresses that would cause brittle materials, such as glass, with minimal plastic deformation ranges, to break.<ref>{{Cite book|title=Structural glass|url=http://books.google.com/books?id=7t9wgJEUWHYC&pg=PA33|page=33|author=Peter Rice, Hugh Dutton|publisher=Taylor & Francis|isbn=0-419-19940-3|year=1995}}</ref>
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| ==References==
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| {{Reflist}}
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| ==See also==
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| {{colbegin|3}}
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| *[[Artificial cranial deformation]]
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| *[[Bending]]
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| *[[Creep (deformation)]]
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| *[[Deflection (engineering)]]
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| *[[Deformable body]]
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| *[[Deformation (mechanics)]]
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| *[[Deformation mechanism maps]]
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| *[[Deformation Monitoring]]
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| *[[Deformation retract]]
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| *[[Deformation theory]]
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| *[[Discontinuous Deformation Analysis]]
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| *[[Elastic (solid mechanics)|Elastic]]
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| *[[Finite deformation tensors]]
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| *[[Malleability]]
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| *[[Modulus of elasticity]]
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| *[[Planar deformation features]]
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| *[[Plasticity (physics)]]
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| *[[Strain tensor]]
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| *[[Strain (materials science)|Strain]]
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| *[[Strength of materials]]
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| *[[Poisson's ratio]]
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| *[[Wood warping]]
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| {{colend}}
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| {{DEFAULTSORT:Deformation (Engineering)}}
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| [[Category:Solid mechanics]]
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| [[Category:Deformation]]
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| [[az:Deformasiya]]
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| [[bg:Деформация]]
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| [[cs:Deformace]]
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| [[de:Verformung]]
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| [[et:Deformatsioon]]
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| [[es:Deformación]]
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| [[eo:Deformiĝo]]
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| [[fa:تغییر شکل (مهندسی)]]
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| [[fr:Déformation des matériaux]]
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| [[gl:Deformación]]
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| [[it:Deformazione]]
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| [[lv:Deformācija]]
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| [[lt:Kūno deformacija]]
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| [[no:Deformasjon]]
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| [[pt:Deformação]]
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| [[simple:Deformation]]
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| [[sk:Deformácia (mechanika)]]
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| [[sv:Deformation]]
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| [[tr:Şekil değiştirme]]
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| [[uk:Деформація]]
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| [[vec:Deformasion]]
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| [[zh:形變]]
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Are you constantly having problems with the PC? Are you always searching for techniques to increase PC performance? Next this is the post you're searching for. Here we'll discuss a few of the many asked issues with regards to having you PC serve you well; how could I make my computer quicker for free? How to create my computer run faster?
We all learn that the registry is the important component of the Windows running program because it stores all information regarding the Dll files, programs found on the computer plus program settings. However, because days by, it happens to be unavoidable which we might encounter registry issue due to a huge amount of invalid, useless and unwelcome entries.
Windows is surprisingly dumb. It only knows how to follow commands plus instructions, that means that when we install a system, which program has to tell Windows precisely what to do. This really is done by storing an "training file" inside the registry of the system. All a computer programs place these "manuals" into the registry, permitting a computer to run a broad array of programs. When you load up 1 of those programs, Windows merely looks up the system file in the registry, and carries out its instructions.
Always see with it that we have installed antivirus, anti-spyware and anti-adware programs and have them updated on a regular basis. This can help stop windows XP running slow.
Google Chrome crashes on Windows 7 if the registry entries are improperly modified. Missing registry keys or registry keys with improper values can cause runtime mistakes plus thereby the issue occurs. We are suggested to scan the entire system registry and review the outcome. Attempt the registry repair procedure using third-party windows registry cleaner software.
S/w connected error handling - If the blue screen bodily memory dump happens following the installation of s/w application or a driver it might be that there is program incompatibility. By booting into secure mode plus removing the software you are able to promptly fix this error. We might additionally try out a "program restore" to revert to an earlier state.
When the registry is corrupt or full of mistakes, the signs may be felt by the computer owner. The slow performance, the frequent program crashes plus the nightmare of all computer owners, the blue screen of death.
There is a lot a good registry cleaner will do for your computer. It may check for plus download changes for Windows, Java and Adobe. Keeping changes present is an important piece of advantageous computer wellness. It will furthermore protect the personal and business confidentiality and your online safety.