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Berkovich Tip
A Berkovich tip is a type of nanoindenter tip used for testing the indentation hardness of a material. It is a three-sided pyramid which is geometrically self-similar. The popular Berkovich now has a very flat profile, with a total included angle of 142.3 degrees and a half angle of 65.27 degrees, measured from the axis to one of the pyramid flats. This Berkovich tip has the same projected area-to-depth ratio as a Vickers indenter. The original tip shape was invented by Russian scientist E.S. Berkovich in the USSR c. 1950, which has a half angle of 65.03 degrees.M.M. Khrushchov & E.S. Berkovich, "Methods of Determining the Hardness of Very Hard Materials: The Hardness of Diamond," ''Zavodskaya Laboratoria'', 1950 (2), p 193 -196 (in Russian). Translated into English by W.G.C and published in ''Industrial Diamond Review'', Vol. 11, Feb 1951, p 42-49 (in English). As it is three sided, it is easier to grind these tips to a sharp point and so is more readily employed for nanoindenta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berkovich
Berkovich ( uk, Беркович) is an Ashkenazi Jewish surname. Notable people with the surname include: *E.S. Berkovich, Russian scientist and inventor of the Berkovich hardness indenter *Eyal Berkovich (born 1972), Israeli football player *Miki Berkovich (born 1954), Israeli basketball player *Vladimir Berkovich, Israeli mathematician **Berkovich space in mathematics *Yuli Berkovich Yuli Berkovich (1944 - 2022) was a scientist who has performed experiments with seed germination in zero gravity, among others, on both the Soviet Mir Space Station and the International Space Station. The seedlings germinated, but died a few days ..., Russian cosmonaut See also * Berkovic * Berković * Berkovits * Berkowitz {{surname, Berkovich Jewish surnames Ukrainian-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoindenter
A nanoindenter is the main component for indentation hardness tests used in nanoindentation. Since the mid-1970s nanoindentation has become the primary method for measuring and testing very small volumes of mechanical properties. Nanoindentation, also called ''depth sensing indentation'' or ''instrumented indentation'', gained popularity with the development of machines that could record small load and displacement with high accuracy and precision. The load displacement data can be used to determine modulus of elasticity, hardness, yield strength, fracture toughness, scratch hardness and wear properties. Types There are many types of nanoindenters in current use differing mainly on their tip geometry. Among the numerous available geometries are three and four sided pyramids, wedges, cones, cylinders, filaments, and spheres. Several geometries have become a well established common standard due to their extended use and well known properties; such as Berkovich, cube corner, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indentation Hardness
Indentation hardness tests are used in mechanical engineering to determine the hardness of a material to deformation. Several such tests exist, wherein the examined material is indented until an impression is formed; these tests can be performed on a macroscopic or microscopic scale. When testing metals, indentation hardness correlates roughly linearly with tensile strength, but it is an imperfect correlation often limited to small ranges of strength and hardness for each indentation geometry. This relation permits economically important nondestructive testing of bulk metal deliveries with lightweight, even portable equipment, such as hand-held Rockwell hardness testers. Material hardness Different techniques are used to quantify material characteristics at smaller scales. Measuring mechanical properties for materials, for instance, of thin films, cannot be done using conventional uniaxial tensile testing. As a result, techniques testing material "hardness" by indenting a materia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vickers Hardness Test
The Vickers hardness test was developed in 1921 by Robert L. Smith and George E. Sandland at Vickers Ltd as an alternative to the Brinell method to measure the hardness of materials. The Vickers test is often easier to use than other hardness tests since the required calculations are independent of the size of the indenter, and the indenter can be used for all materials irrespective of hardness. The basic principle, as with all common measures of hardness, is to observe a material's ability to resist plastic deformation from a standard source. The Vickers test can be used for all metals and has one of the widest scales among hardness tests. The unit of hardness given by the test is known as the Vickers Pyramid Number (HV) or Diamond Pyramid Hardness (DPH). The hardness number can be converted into units of pascals, but should not be confused with pressure, which uses the same units. The hardness number is determined by the load over the surface area of the indentation and not t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoindentation
Nanoindentation, also called instrumented indentation testing, is a variety of indentation hardness tests applied to small volumes. Indentation is perhaps the most commonly applied means of testing the mechanical properties of materials. The nanoindentation technique was developed in the mid-1970s to measure the hardness of small volumes of material. Background In a traditional indentation test (macro or micro indentation), a hard tip whose mechanical properties are known (frequently made of a very hard material like diamond) is pressed into a sample whose properties are unknown. The load placed on the indenter tip is increased as the tip penetrates further into the specimen and soon reaches a user-defined value. At this point, the load may be held constant for a period or removed. The area of the residual indentation in the sample is measured and the hardness, H, is defined as the maximum load, P_, divided by the residual indentation area, A_r: :H=\frac . For most techniques, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardness Tests
In materials science, hardness (antonym: softness) is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion. In general, different materials differ in their hardness; for example hard metals such as titanium and beryllium are harder than soft metals such as sodium and metallic tin, or wood and common plastics. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter. Measuring hardness There are three main types of hardness measurements: ''scratch'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Inventions
This timeline of Russian Innovation encompasses key events in the history of technology in Russia, from the Grand Duchy of Moscow up to the Russian Federation. The entries in this timeline fall into the following categories: * indigenous inventions, like airliners, AC transformers, radio receivers, television, artificial satellites, ICBMs * uniquely Russian products, objects and events, like Saint Basil's Cathedral, Matryoshka dolls, Russian vodka * products and objects with superlative characteristics, like the Tsar Bomba, the AK-47, and the Typhoon-class submarine * scientific and medical discoveries, like the periodic law, vitamins and stem cells This timeline includes scientific and medical discoveries, products and technologies introduced by various peoples of Russia and its predecessor states, regardless of ethnicity, and also lists inventions by naturalized immigrant citizens. Certain innovations achieved internationally may also appear in this timeline in cases wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
