|
|
| (One intermediate revision by one other user not shown) |
| Line 1: |
Line 1: |
| {{About|deformation in engineering|a more rigorous treatment|Deformation (mechanics)}}
| | Most folks have this habit of doing all of the stuff by themselves, irrespective of how critical or simple they are! These folks won't let others interfere in their matters. While this stance might function in other areas of existence, it's really not the best way to reply when you need to fix a Windows registry. There are some jobs like removing spywares, virus because well as obsolete registry entries, that are best left to expert softwares. In this short article I will tell you why it is very important to fix Windows registry NOW!<br><br>So one day my computer suddenly began being strange. I was thus frustrated, because my files were missing, plus I cannot open the files that I needed, plus then, suddenly, everything stopped functioning!<br><br>The 'registry' is a central database that stores information, settings plus choices for your computer. It's actually the many prevalent reason why XP runs slow and should you fix this problem, we can make a computer run a lot faster. The problem is that the 'registry' stores a lot of settings plus details regarding your PC... and because Windows needs to utilize a lot of of these settings, any corrupted or damaged ones usually directly affect the speed of your program.<br><br>The 1328 error is a usual problem caused by a program being unable to correctly procedure numerous updates for your program or Microsoft Office. If you have this error, it generally signifies which your computer is either unable to read the actual update file or a computer has difficulties with all the settings it's utilizing to run. To fix this problem, you initially should change / fix any issues which the computer has with its update files, and then repair some of the issues which the program might have.<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 lead to runtime mistakes plus thereby the issue occurs. We are suggested to scan the whole program registry plus review the result. Attempt the registry repair process utilizing third-party [http://bestregistrycleanerfix.com/tune-up-utilities tuneup utilities] software.<br><br>Files with the DOC extension are moreover susceptible to viruses, yet this could be solved by wise antivirus programs. Another issue is the fact that .doc files could be corrupted, unreadable or damaged due to spyware, adware, and malware. These cases will avoid consumers from correctly opening DOC files. This really is when powerful registry cleaners become useful.<br><br>It is important which we remove obsolete registry entries from your system regularly, if you would like the system to run quicker, that is. If you don't keep the registry clean, a time comes whenever the system might stop functioning altogether. Next, your just way will be to reformat the hard drive and begin over!<br><br>All of these problems might be easily solved by the clean registry. Installing our registry cleaner can allow you to use a PC without worries behind. You might capable to employ you program without being scared that it's going to crash in the middle. Our registry cleaner can fix a host of errors on the PC, identifying lost, invalid or corrupt settings in a registry. |
| {{Refimprove|date=September 2008}}
| |
| [[Image:DeformationDueToCompression.png|thumb|right|58px|Compressive stress results in deformation which shortens the object but also expands it outwards.]]
| |
| | |
| In [[materials science]], '''deformation''' is a change in the shape or size of an object due to
| |
| * an applied [[force (physics)|force]] (the deformation energy in this case is transferred through work) or
| |
| * a change in temperature (the deformation energy in this case is transferred through heat).
| |
| 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).
| |
| | |
| 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> | |
| | |
| Deformation is often described as [[strain (materials science)|strain]].
| |
| | |
| 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]].
| |
| | |
| 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.
| |
| | |
| The concept of a [[rigid body]] can be applied if the deformation is negligible.
| |
| | |
| ==Types of deformation==
| |
| 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]].
| |
| | |
| [[Image:Stress Strain Ductile Material.png|thumb|right|450px|Typical stress vs. strain diagram with the various stages of deformation.]]
| |
| | |
| ===Elastic deformation===
| |
| {{more|Elasticity (physics)}}
| |
| 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.
| |
| | |
| Linear elastic deformation is governed by [[Hooke's law]], which states:
| |
| | |
| :<math>\sigma = E \varepsilon</math>
| |
| | |
| 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.
| |
| | |
| 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>
| |
| | |
| ===Plastic deformation===
| |
| {{See also|Plasticity (physics)}}
| |
| | |
| 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.
| |
| | |
| 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.
| |
| | |
| ====Metal fatigue====
| |
| 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.
| |
| | |
| 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.
| |
| | |
| ====Compressive failure====
| |
| Usually, compressive stress applied to bars, [[column]]s, etc. leads to shortening.
| |
| | |
| 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.).
| |
| | |
| 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.
| |
| | |
| ===Fracture===
| |
| [[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.]]
| |
| {{See also|Fracture mechanics}}
| |
| {{See also|Concrete fracture analysis}}
| |
| 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.
| |
| | |
| ==Misconceptions==
| |
| 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>
| |
| | |
| ==References==
| |
| {{Reflist}}
| |
| | |
| ==See also==
| |
| {{colbegin|3}}
| |
| *[[Artificial cranial deformation]]
| |
| *[[Bending]]
| |
| *[[Creep (deformation)]]
| |
| *[[Deflection (engineering)]]
| |
| *[[Deformable body]]
| |
| *[[Deformation (mechanics)]]
| |
| *[[Deformation mechanism maps]]
| |
| *[[Deformation Monitoring]]
| |
| *[[Deformation retract]]
| |
| *[[Deformation theory]]
| |
| *[[Discontinuous Deformation Analysis]]
| |
| *[[Elastic (solid mechanics)|Elastic]]
| |
| *[[Finite deformation tensors]]
| |
| *[[Malleability]]
| |
| *[[Modulus of elasticity]]
| |
| *[[Planar deformation features]]
| |
| *[[Plasticity (physics)]]
| |
| *[[Strain tensor]]
| |
| *[[Strain (materials science)|Strain]]
| |
| *[[Strength of materials]]
| |
| *[[Poisson's ratio]]
| |
| *[[Wood warping]]
| |
| {{colend}}
| |
| | |
| {{DEFAULTSORT:Deformation (Engineering)}}
| |
| [[Category:Solid mechanics]]
| |
| [[Category:Deformation]]
| |
| | |
| [[az:Deformasiya]]
| |
| [[bg:Деформация]]
| |
| [[cs:Deformace]]
| |
| [[de:Verformung]]
| |
| [[et:Deformatsioon]]
| |
| [[es:Deformación]]
| |
| [[eo:Deformiĝo]]
| |
| [[fa:تغییر شکل (مهندسی)]]
| |
| [[fr:Déformation des matériaux]]
| |
| [[gl:Deformación]]
| |
| [[it:Deformazione]]
| |
| [[lv:Deformācija]]
| |
| [[lt:Kūno deformacija]]
| |
| [[no:Deformasjon]]
| |
| [[pt:Deformação]]
| |
| [[simple:Deformation]]
| |
| [[sk:Deformácia (mechanika)]]
| |
| [[sv:Deformation]]
| |
| [[tr:Şekil değiştirme]]
| |
| [[uk:Деформація]]
| |
| [[vec:Deformasion]]
| |
| [[zh:形變]]
| |
Most folks have this habit of doing all of the stuff by themselves, irrespective of how critical or simple they are! These folks won't let others interfere in their matters. While this stance might function in other areas of existence, it's really not the best way to reply when you need to fix a Windows registry. There are some jobs like removing spywares, virus because well as obsolete registry entries, that are best left to expert softwares. In this short article I will tell you why it is very important to fix Windows registry NOW!
So one day my computer suddenly began being strange. I was thus frustrated, because my files were missing, plus I cannot open the files that I needed, plus then, suddenly, everything stopped functioning!
The 'registry' is a central database that stores information, settings plus choices for your computer. It's actually the many prevalent reason why XP runs slow and should you fix this problem, we can make a computer run a lot faster. The problem is that the 'registry' stores a lot of settings plus details regarding your PC... and because Windows needs to utilize a lot of of these settings, any corrupted or damaged ones usually directly affect the speed of your program.
The 1328 error is a usual problem caused by a program being unable to correctly procedure numerous updates for your program or Microsoft Office. If you have this error, it generally signifies which your computer is either unable to read the actual update file or a computer has difficulties with all the settings it's utilizing to run. To fix this problem, you initially should change / fix any issues which the computer has with its update files, and then repair some of the issues which the program might have.
Google Chrome crashes on Windows 7 if the registry entries are improperly modified. Missing registry keys or registry keys with improper values can lead to runtime mistakes plus thereby the issue occurs. We are suggested to scan the whole program registry plus review the result. Attempt the registry repair process utilizing third-party tuneup utilities software.
Files with the DOC extension are moreover susceptible to viruses, yet this could be solved by wise antivirus programs. Another issue is the fact that .doc files could be corrupted, unreadable or damaged due to spyware, adware, and malware. These cases will avoid consumers from correctly opening DOC files. This really is when powerful registry cleaners become useful.
It is important which we remove obsolete registry entries from your system regularly, if you would like the system to run quicker, that is. If you don't keep the registry clean, a time comes whenever the system might stop functioning altogether. Next, your just way will be to reformat the hard drive and begin over!
All of these problems might be easily solved by the clean registry. Installing our registry cleaner can allow you to use a PC without worries behind. You might capable to employ you program without being scared that it's going to crash in the middle. Our registry cleaner can fix a host of errors on the PC, identifying lost, invalid or corrupt settings in a registry.