- Severe plastic deformation
Image HPT.png thumb 200px During the HPT process, the material experiences shear deformation between a fixed and a rotating anvil, without losing its original dimensions. Orphan date October 2010 One source date August 2009 Severe plastic deformation SPD is a generic term describing a group of metalworking techniques involving very large strains which are imposed without introducing any significant changes in the overall dimensions of the specimen or work piece. A further defining feature of SPD techniques is that the preservation of shape is achieved due to special tool geometries which prevent the free flow of material and thereby produce a significant hydrostatic pressure . The presence of a high hydrostatic pressure, in combination with large shear strains, is essential for producing high densities of Crystallographic defect crystal lattice defects , particularly dislocations , which can result in a significant refining of the grains. As the dimensions of the work piece practically do not change in an SPD operation, the process may be applied repeatedly to impose exceptionally high strains. Optimization of routes and regimes of SPD can eventually introduce an extremely fine microstructure into the processed material which will extend, reasonably homogeneously, throughout the bulk. A distinctive feature of these ultrafine grained materials is that they contain a high fraction of grain boundaries having high angles of misorientation. Image ECAP.png thumb During the ECAP process, the material is pressed through an angular die and experiences shear deformation, without changing ... shear deformation and it led to the award of the Nobel Prize in Physics in 1946. Very successful ... Materials from Severe Plastic Deformation , Prog. Mater. Sci. 45, 103 189 2000 . ref ref name ... Bulk Ultrafine Grained Materials by Severe Plastic Deformation , JOM 58 4 , 33 39 2006 ref ... processing. ref name SPD References reflist Category Deformation Category Metal forming fa ... more details
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- Discontinuous Deformation Analysis
Discontinuous Deformation Analysis DDA is a type of discrete element method originally proposed by Shi GH Shi in 1988. DDA is somewhat similar to the finite element method for solving stress displacement problems, but accounts for the interaction of independent particles blocks along discontinuities in fractured and jointed rock masses . DDA is typically formulated as a work energy method, and can ... at present discontinuous deformation analysis open source project located in Sourceforge web site. Image Dda2.JPG 250px Image Dda3.JPG 250px Selected References Hsiung SM. Discontinuous deformation ... 7 10, Washington DC 2001. Jing L. Formulation of discontinuous deformation analysis DDA an implicit ... of fluid flow and solid deformation for fractured rocks with discontinuous deformation analysis ... the effect of water, excavation sequence and rock reinforcement with discontinuous deformation analysis ... with third order displacement function. In Salami MR, Banks D, editors. Discontinuous deformation ... deformation analysis for jointed rock masses. Int J Rock Mech Min Sci Geomech Abstr 1996 33 671 94. Ma MY. Development of discontinuous deformation analysis, the first ten years 1986 1996. Ma MY, Zaman M, Zhu JH. Discontinuous deformation analysis using the third order displacement function. In Salami MR, Banks D, editors. Discontinuous deformation analysis DDA and simulations of discontinuous ... with discontinuous deformation analysis DDA algorithm. Int J Rock Mech Min Sci Geomech Abstr 2006 43 661 670. Roozbeh Grayeli, Ali Mortazavi. Discontinuous deformation analysis with second order ... system modeling by discontinuous deformation analysis. Computational Mechanics Publications 1993. Shi GH. Discontinuous deformation analysis technical note. First international forum on discontinuous deformation analysis, June 12 14. Berkeley, California 1996. Te Chin K. Improved modeling of rock ... Deformation ... more details
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- Voronoi deformation density
Voronoi deformation density VDD is a method employed in computational chemistry to compute the Partial charge atomic charge distribution of a molecule in order to provide information about its chemical properties. The method is based on the partitioning of space into non overlapping atomic areas modelled as Voronoi diagram Voronoi cells and then computing the deformation density within those cells i.e. the extent to which electron density differs from that of an unbonded atom . ref Voronoi Deformation Density VDD Charges Assessment of the Mulliken, Bader, Hirshfeld, Weinhold, and VDD Methods for Charge Analysis C. Fonseca Guerra, J.W. Handgraaf, E.J. Baerends & F.M Bickelhaupt J. Comp. Chem. 2004 25 , 189 210 http www3.interscience.wiley.com journal 106566098 abstract abstract ref The VDD charge Q sub A sub of atom A is computed as the numerical integral of the deformation density r r sub B sub sub B sub r associated with the formation of the molecule from its atoms over the volume of the Voronoi cell of atom A math Q A int limits text Voronoi cell A Big rho mathbf r sum B rho B mathbf r Big d mathbf r math The Voronoi cell of atom A is defined as the compartment of space bounded by the bond midplanes on and perpendicular to all bond axes between nucleus A and its neighboring nuclei cf. the Wigner Seitz cell s in crystals . The Voronoi cell of atom A is therefore the region of space closer to nucleus A than to any other nucleus. Furthermore, r is the electron density of the molecule and sub B sub sub B sub r the superposition of atomic densities sub B sub of a fictitious promolecule without chemical interactions that is associated with the situation in which all atoms are neutral. Note that an Partial charge atomic charge is not a observable physical observable . Nevertheless, it has been proven a useful means to compactly describe and analyze the electron density distribution in a molecule , which is important for understanding the behavior of the latter ... more details
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- Net Lake-Vermilion Lake Deformation Zone
File Strathy Township geology.png thumb right Geologic map of Strathy Township displaying the location of the Net Lake Vermilion Lake Deformation Zone. The Net Lake Vermilion Lake Deformation Zone , also known as the Net Lake Vermilion Lake Zone of Deformation , is a zone of deformation in Temagami , Ontario , Canada , extending from Vermilion Lake to Net Lake in a northeasterly direction. ref cite journal id AFRI OFR5591 title Exploration Potential for Base and Precious Metal Mineralization in Part of Strathy Township publisher Government of Ontario last1 Fyon first1 A.J. last2 Crocket first2 J.H. page 20 year 1986 accessdate 2011 01 04 ref See also Link Lake Deformation Zone Northeast Arm Deformation Zone Tasse Lake Deformation Zone References reflist Category Geologic faults of Temagami Category Strathy Township Canada geology stub Ontario stub ... more details
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- Torsional strain
Torsional strain may refer to Deformation mechanics Strain chemistry Torsional strain Strain chemistry Disambiguation ... more details
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- Slip line field
Orphan date February 2009 A Slip Line Field or Slip line field theory , is a technique often used to analyze the stress mechanics stress es and forces involved in the major deformation engineering deformation of metal s, using theories based around maximum shear stress . Category Metallurgy Category Mechanical engineering mech engineering stub ... more details
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- Elastic
wiktionarypar elastic Elastic may refer to Elastic, a colloquial noun for certain kinds of elastomer s and stretchable fabrics Elastic collision , a term describing collisions in which kinetic energy is conserved Deformation engineering Elastic deformation Elastic deformation , a reversible deformation of a material Elasticity physics , the physical property of a material that returns to its original shape Elasticity economics , a term used to describe the responsiveness of demand or supply Elastic, an alternative name for the skipping game Chinese jump rope Elastic album Elastic album , an album by jazz saxophonist Joshua Redman A Rubber band or bungee cord Elastic Superheroes ex, Mr. Incredible, Elastigirl, etc. See also lookfrom intitle Elasticity disambiguation Flex disambiguation Stretch disambiguation disambig ja ... more details
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- Formal moduli
In mathematics , formal moduli are an aspect of the theory of moduli space s of algebraic varieties or vector bundle s, for example , closely linked to deformation theory and formal geometry . Roughly speaking, deformation theory can provide the Taylor polynomial level of information about deformations, while formal moduli theory can assemble consistent Taylor polynomials to make a formal power series theory. The step to moduli spaces, properly speaking, is an algebraization question, and has been largely put on a firm basis by Artin s approximation theorem . A formal universal deformation is by definition a formal scheme over a complete local ring , with special fiber the scheme over a field being studied, and with a universal property amongst such set ups. The local ring in question is then the carrier of the formal moduli. References Springer id d d030700 title Deformation Category Moduli theory ... more details
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- Shelling
Shelling may refer to Shell projectile , explosive used in wars Searching for seashell s Shelling topology Wheelset rail transport Wheelset deformation , that occur when the wheel has been worn out disambig ... more details
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- Simple shear
critical buildings to survive earthquakes undamaged. Simple shear in solid mechanics Main Deformation mechanics In solid mechanics, a simple shear deformation is defined as an Deformation mechanics Plane deformation isochoric plane deformation in which there are a set of line elements with a given reference orientation that do not change length and orientation during the deformation. ref name ... reference orientation in which line elements do not deform during the deformation and math mathbf e 1 mathbf e 2 math is the plane of deformation, then the deformation gradient in simple shear ... . math We can also write the deformation gradient as math boldsymbol F boldsymbol mathit 1 gamma mathbf e 1 otimes mathbf e 2. math See also Deformation mechanics Infinitesimal strain theory Finite strain ... more details
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- Application of tensor theory in engineering
Unreferenced date December 2009 Tensor s are frequently used in engineering to describe measured physical quantity quantities . Common applications Measuring Deformation mechanics deformations finite deformation tensors and Strain materials science strain strain tensor in continuum mechanics Representing diffusion as a tensor in Diffusion tensor imaging Describing moment of inertia moments of inertia as the Moment of inertia Moment of inertia tensor inertia tensor See also Application of tensor theory in physics Mathematical physics Tensor DEFAULTSORT Application Of Tensor Theory In Engineering Category Tensors ... more details
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- Unimorph
File Unimorph.svg thumb Unimorph cantilever A unimorph is a cantilever that consists of one active layer and one inactive layer. ref http robotics.eecs.berkeley.edu ronf PAPERS icra01b.pdf ref In the case where active layer is piezoelectric , deformation in that layer may be induced by the application of an electric field. This deformation induces a bending displacement in the cantilever. The inactive layer may be fabricated from a non piezoelectric material. See also bimorph References reflist Category Piezoelectric materials zh ... more details
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- Seismogenic layer
Unreferenced date October 2006 The seismogenic layer is the range of depths within the crust geology crust or lithosphere over which most earthquake s are initiated. Typically in continental crust this is in the uppermost 15 km. The base of this layer represents the downwards change in deformation mechanism from elastic and frictional processes associated with brittle faulting to a generally aseismic zone where Creep deformation ductile creep becomes the dominant process. The location of this change in deformation style is sometimes referred to as the Brittle ductile transition zone . DEFAULTSORT Seismogenic Layer Category Structure of the Earth Category Seismology and earthquake terminology Geophysics stub ... more details
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- Duality (mechanical engineering)
In mechanical engineering , many terms are associated into pairs called duals . A dual of a relationship is formed by interchanging force stress and deformation strain in an expression. Here is a partial list of mechanical dualities force &mdash deformation engineering deformation stress physics stress &mdash Strain materials science strain stiffness method &mdash flexibility method Examples Constitutive relation stress and strain Hooke s law . math sigma E varepsilon iff varepsilon frac 1 E sigma , math See also Duality electrical circuits References Fung, Y. C., A First Course in CONTINUUM MECHANICS , 2nd edition, Prentice Hall, Inc. 1977 Category Mechanical engineering Category Duality theories Mechanical engineering fa ... more details
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- Kodaira?Spencer map
In mathematics, the Kodaira Spencer map , introduced by Kunihiko Kodaira and Donald C. Spencer , is a map associated to a deformation of a scheme or complex manifold X , taking a tangent space of a point of the deformation space to the first cohomology group of the sheaf of vector fields on X . References Citation last1 Kodaira first1 Kunihiko title Complex manifolds and deformation of complex structures url http books.google.com books?id 4RZS4qxmQ gC publisher Springer Verlag location Berlin, New York series Grundlehren der Mathematischen Wissenschaften Fundamental Principles of Mathematical Sciences isbn 978 0 387 96188 0 id MR 815922 year 1986 volume 283 Category Algebraic geometry mathematics stub ... more details
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- Ellrod index
Orphan date October 2008 In meteorology Ellrod index is a technique for forecasting clear air turbulence . It is calculated based on the product of horizontal deformation and vertical wind shear derived from numerical model forecast winds aloft. The deformation predictors are calculated using following information. Shearing deformation math DSH frac dv dx frac du dy math . Stretching deformation math DST frac du dx frac dv dy math . Where u and v are horizontal components of the wind. Total deformation equals to math DEF sqrt DSH 2 DST 2 math . Convergence math CVG frac du dx frac dv dy math Vertical wind shear math VWS frac Delta V Delta Z math And the resulting index is given by math EI VWS times DEF CVG math To correspond to clear air turbulence pilot report s the following table can be used class wikitable style text align center border 5 Reported EI value threshold Light Moderate 4 Moderate 8 Moderate Severe 12 http aviationweather.gov exp ellrod info.php?mdl NAM Aviation Weather Center Help http aviationweather.gov exp ellrod nam Aviation Weather Center EI display Category Basic meteorological concepts and phenomena Category Turbulence ... more details
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- Formability
Formability is the ability of a given metal workpiece to undergo plastic deformation without being damaged. The plastic deformation capacity of metal lic materials, however, is limited to a certain extent, at which point, the material could experience tearing or fracture breakage . Processes affected by the formability of a material include rolling , extrusion , forging , rollforming , Stamping metalworking stamping , and hydroforming . Fracture strain A general parameter that indicates the formability ... test of flat specimens, pursuant to EN 10002 . It is important to note that deformation is homogeneous ... is not an engineering strain since distribution of the deformation is inhomogeneous within the reference ... of Sheet Metal Forming Material Behavior and Deformation analysis , Plenum Press, 1978, ISBN ... of localized plastic deformation . Whereas more or less homogeneous deformation takes place in and around the subsequent neck location in the early stable deformation stage, almost all deformation is concentrated in the neck zone during the quasi stable and instable deformation phase. This leads ... possible, deformation which a sheet material may undergo during any stage of the stamping process. These limits depend on the deformation mode and the ratio of the surface strains. The major surface strain has a minimum value when plane strain deformation occurs, which means that the corresponding ... with outstanding deep drawability behave anisotropically see anisotropy . Plastic deformation ... material property indicating the ratio between width deformation and thickness deformation ... is seen in the deformation paths of the material that are concentrated in the extreme left of the diagram ... any tearing is ductile fracture after plastic deformation ductility . This may occur as a result of bending or shear deformation inplane or through the thickness . The failure mechanism may be due ... appear when deformation of the material between the voids has exceeded the limit. Extensive research ... more details
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- Poikiloblast
Unreferenced date April 2011 Orphan date February 2009 A poikiloblast is a porphyroblast mineral with small inclusion mineral inclusions of the previous rock in it. From the texture if any shown in the inclusion, the deformation history of the rock can be interpreted, as the inclusions are always older than the porphyroblast. Category Petrology petrology stub ... more details
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- Saber tibia
Orphan date February 2009 Saber tibia is a deformation of the tibia as a result of Syphilis Tertiary tertiary syphilis . It manifests as a forward convex shape created by Gumma pathology gumma formation and Shin splints periostitis . References American Heritage Medical Dictionary Category Bones of the lower limb med stub ... more details
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- Eclabium
Eclabium means the turning outwards of a lip. Eclabium comes from the Greek word ek meaning out, and the Latin word labium meaning lip. This deformation occurs in most babies born with Harlequin type ichthyosis ref http www.medfriendly.com eclabium.html ref . References Reflist 2 Category Lip disorders disease stub ... more details
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- Dominant functor
Multiple issues orphan April 2012 wikify March 2012 unreferenced March 2012 A functor F C to D is said to be dominant if every object of D is a Deformation retract retract of an object of the form F x for some object X of C. Category Functors categorytheory stub ... more details
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- Necking (engineering)
sectional area. Neck stability As deformation proceeds the geometric instability causes strain to continue ... more details
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- Contraflexure
Unreferenced date December 2009 In a bending Beam structure beam , a point is known as a point of contraflexure if it is a location at which no bending occurs. In a bending moment diagram, it is the point at which the bending moment curve intersects with the zero line. Knowing the place of the contraflexure is especially useful when designing reinforced concrete or structural steel beams and also for designing bridges. Flexural reinforcement may be reduced at this point. However, to omit rebar reinforcement at the point of contraflexure entirely is inadvisable as the actual location is unlikely to realistically be defined with confidence. Additionally, an adequate quantity of reinforcement should extend beyond the point of contraflexure to develop bond strength and to facilitate shear force transfer. See also Engineering mechanics Strength of materials Deformation engineering Deformation Inflection point Flexural Rigidity flexural stress Category Solid mechanics Engineering stub ... more details
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- Driving cap
Unreferenced date June 2009 For the article of clothing Flat cap A driving cap is a special type of pipe cap used to provide a striking surface for a hammer while simultaneously protecting the end of the pipe from Deformation engineering deformation . A driving cap is made of much thicker or more durable material than a standard pipe cap and is always removed once installation is complete. Driving caps serve no function in the operation of a pipe and may even be incapable of doing so. This is because the driving cap is Casting cast from a material selected for its strength and not its corrosion resistance. Thus replacement of the driving cap with a different fitting becomes necessary to prevent failures in materials handling pipe. Also, driving caps are not attractive in appearance, which is detrimental in residential and ornamental applications. Category Plumbing ... more details
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- Interfering thread nut
An interfering thread nut is a type of locknut that has an over sized root diameter. This creates an interference between the nut hardware nut and the fastener, plastic deformation plastically deforming the screw thread threads on the fastener. Due to this deformation they are usually only used on permanent or semi permanent installations. ref name barrett Citation last Barrett first Rich title Fastener Design Manual url http www.tcnj.edu rgraham barrett manual1 A.html accessdate 2008 12 02 . ref A variation of this nut is the tapered thread nut . It utilizes a wikt tapered tapered thread to achieve the interference. The nut goes on easily, because the thread diameter starts at a standard size as the nut is further threaded on it begins to lock, much like a distorted thread locknut . ref name barrett References reflist Category Nuts hardware ... more details
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