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Schmid's Law
In materials science, Schmid's law (also Schmid factor, and or german: Schmid'scher Orientierungsfaktor, lit=Schmid's orientation factor, label=none.) describes the slip plane and the slip direction of a stressed material, which can resolve the most shear stress. Schmid's Law states that the critically resolved shear stress () is equal to the stress applied to the material () multiplied by the cosine of the angle with the vector normal to the glide plane () and the cosine of the angle with the glide direction (). Which can be expressed as: : \tau = m \sigma where is known as the Schmid factor :m = \cos(\phi) \cos(\lambda) Both factors and are measured in stress units, which is calculated the same way as pressure (force divided by area). and are angles. The factor is named after Erich Schmid who coauthored a book with Walter Boas introducing the concept in 1935. See also *Critical resolved shear stress In materials science, critical resolved shear stress (CRSS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fachbuchverlag Leipzig Im Carl Hanser Verlag
The (''fv''; English: Specialist book publisher Leipzig) is a publisher that was founded in early 1949 by several shareholders (including FDGB, ). The first managing director was . From 1960 to 1990 the specialist book publisher was a state-owned enterprise (VEB). It was one of the two most renowned technical-scientific publishers in the German Democratic Republic, whose specialist books were also widely distributed in the Federal Republic of Germany. The books were very popular with West-German students because of their low price, but above all because of the good didactics. It also published specialist journals. In 1995, the specialist book publisher was taken over by the Munich Carl Hanser Verlag and continued to exist there as an imprint. Under the brand, some of the editors of Carl Hanser Verlag continue to publish around 60 specialist books a year. The subject areas are general technology, mechanical engineering, electrical engineering, computer science, environmental and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slip (materials Science)
In materials science, slip is the large displacement of one part of a crystal relative to another part along crystallographic planes and directions. Slip occurs by the passage of dislocations on close/packed planes, which are planes containing the greatest number of atoms per area and in close-packed directions (most atoms per length). Close-packed planes are known as ''slip'' or ''glide planes''. A slip system describes the set of symmetrically identical slip planes and associated family of slip directions for which dislocation motion can easily occur and lead to plastic deformation. The magnitude and direction of slip are represented by the Burgers vector, . An external force makes parts of the crystal lattice glide along each other, changing the material's geometry. A critical resolved shear stress is required to initiate a slip., Hull D., Bacon, D.J (2001); "Introduction to Dislocations", 4th ed., Slip systems Face centered cubic crystals Slip in face centered cubic (f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress (mechanics)
In continuum mechanics, stress is a physical quantity. It is a quantity that describes the magnitude of forces that cause deformation. Stress is defined as ''force per unit area''. When an object is pulled apart by a force it will cause elongation which is also known as deformation, like the stretching of an elastic band, it is called tensile stress. But, when the forces result in the compression of an object, it is called compressive stress. It results when forces like tension or compression act on a body. The greater this force and the smaller the cross-sectional area of the body on which it acts, the greater the stress. Therefore, stress is measured in newton per square meter (N/m2) or pascal (Pa). Stress expresses the internal forces that neighbouring particles of a continuous material exert on each other, while strain is the measure of the deformation of the material. For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Stress
Shear stress, often denoted by (Greek: tau), is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. ''Normal stress'', on the other hand, arises from the force vector component perpendicular to the material cross section on which it acts. General shear stress The formula to calculate average shear stress is force per unit area.: : \tau = , where: : = the shear stress; : = the force applied; : = the cross-sectional area of material with area parallel to the applied force vector. Other forms Wall shear stress Wall shear stress expresses the retarding force (per unit area) from a wall in the layers of a fluid flowing next to the wall. It is defined as: \tau_w:=\mu\left(\frac\right)_ Where \mu is the dynamic viscosity, u the flow velocity and y the distance from the wall. It is used, for example, in the description of arterial blood flow in which case which ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Resolved Shear Stress
In materials science, critical resolved shear stress (CRSS) is the component of shear stress, resolved in the direction of slip, necessary to initiate slip in a grain. Resolved shear stress (RSS) is the shear component of an applied tensile or compressive stress resolved along a slip plane that is other than perpendicular or parallel to the stress axis. The RSS is related to the applied stress by a geometrical factor, , typically the Schmid factor: :\tau_\text = \sigma_\text m = \sigma_\text (\cos \phi \cos \lambda) where is the magnitude of the applied tensile stress, is the angle between the normal of the slip plane and the direction of the applied force, and is the angle between the slip direction and the direction of the applied force. The Schmid factor is most applicable to FCC single-crystal metals, but for polycrystal metals the Taylor factor has been shown to be more accurate.Taylor, Sir Geoffrey Ingram. Plastic strain in metals. 1938. The CRSS is the value of re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal (geometry)
In geometry, a normal is an object such as a line, ray, or vector that is perpendicular to a given object. For example, the normal line to a plane curve at a given point is the (infinite) line perpendicular to the tangent line to the curve at the point. A normal vector may have length one (a unit vector) or its length may represent the curvature of the object (a ''curvature vector''); its algebraic sign may indicate sides (interior or exterior). In three dimensions, a surface normal, or simply normal, to a surface at point P is a vector perpendicular to the tangent plane of the surface at P. The word "normal" is also used as an adjective: a line ''normal'' to a plane, the ''normal'' component of a force, the normal vector, etc. The concept of normality generalizes to orthogonality (right angles). The concept has been generalized to differentiable manifolds of arbitrary dimension embedded in a Euclidean space. The normal vector space or normal space of a manifold at point P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and even by industry. Further, both spellings are often used ''within'' a particular industry or country. Industries in British English-speaking countries typically use the "gauge" spelling. is the pressure relative to the ambient pressure. Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as of this. Manometric u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newton (N). Force is represented by the symbol (formerly ). The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object. Concepts related to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque, which produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erich Schmid (physicist)
Erich Schmid (4 May 1896, in Bruck an der Mur – 22 October 1983, in Vienna) was a physicist from Austria. He made important discoveries in the field of crystal plasticity. Schmid studied physics and mathematics at the University of Vienna and received his doctorate in 1920 under the supervision of Felix Ehrenhaft. He then became the assistant of Ludwig Flamm. In 1951 he accepted a position at the University of Vienna and stayed there until retiring in 1967. One of his most successful contributions is the book "''Plasticity of Crystals: with special reference to metals''" ("''Kristallplastizität: Mit Besonderer Berücksichtigung der Metalle''") which he coauthored with Walter Boas. In 1960 the Austrian Academy of Sciences awarded him the Erwin Schrödinger Prize The Erwin Schrödinger Prize (German: Erwin Schrödinger-Preis) is an annual award presented by the Austrian Academy of Sciences for lifetime achievement by Austrians in the fields of mathematics and natural sciences. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Boas is named in his honour.
Walter Moritz Boas FAA (10 February 1904 – 12 May 1982) was a German-Australian metallurgist. First published in ''Australian Dictionary of Biography'', Volume 17, (MUP), 2007. Boas was born in Berlin, Germany and was educated at the Berlin Institute of Technology (Dip. Engin. 1928, Dr.-Ing. 1930). After several positions at German and Swiss institutions, Boas became a lecturer in metallurgy at University of Melbourne in 1938; then from 1940 to 1947, senior lecturer. From 1947 to 1949, Boas was principal research officer, CSIR Division of Tribophysics; and from 1949 to 1969 chief of the division. The Walter Boas Medal of the Australian Institute of Physics The Australian Institute of Physics was established in 1963, when it replaced the Australian Branch of the British Institute of Physics based in London. Refe ...
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