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Sendust
Sendust is a magnetic metal powder that was invented by Hakaru Masumoto at Tohoku Imperial University in Sendai, Japan circa 1936 as an alternative to permalloy in inductor applications for telephone networks. Sendust composition is typically 85% iron, 9% silicon and 6% aluminium. The powder is sintered into cores to manufacture inductors. Sendust cores have high magnetic permeability (up to 140 000), low loss, low coercivity (5 A/m) good temperature stability and saturation flux density up to . Due to its chemical composition and crystallographic structure Sendust exhibits simultaneously zero magnetostriction and zero magnetocrystalline anisotropy constant K1. Sendust is harder than permalloy, and is thus useful in abrasive wear applications such as magnetic recording heads. See also * Alperm External links Comparison of molybdenum permalloy with sendustas energy storage inductors (PDF Portable document format (PDF), standardized as ISO 32000, is a file for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Permeability
In electromagnetism, permeability is the measure of magnetization produced in a material in response to an applied magnetic field. Permeability is typically represented by the (italicized) Greek letter ''μ''. It is the ratio of the magnetic induction B to the magnetizing field H in a material. The term was coined by William Thomson, 1st Baron Kelvin in 1872, and used alongside permittivity by Oliver Heaviside in 1885. The reciprocal of permeability is magnetic reluctivity. In SI units, permeability is measured in henries per meter (H/m), or equivalently in newtons per ampere squared (N/A2). The permeability constant ''μ''0, also known as the magnetic constant or the permeability of free space, is the proportionality between magnetic induction and magnetizing force when forming a magnetic field in a classical vacuum. A closely related property of materials is magnetic susceptibility, which is a dimensionless proportionality factor that indicates the degree of magnet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permalloy
Permalloy () is a nickel–iron magnetic alloy, with about 80% nickel and 20% iron content. Invented in 1914 by physicist Gustav Elmen at Bell Telephone Laboratories, it is notable for its very high magnetic permeability, which makes it useful as a magnetic core material in electrical and electronic equipment, and also in magnetic shielding to block magnetic fields. Commercial permalloy alloys typically have relative permeability of around 100,000, compared to several thousand for ordinary steel. In addition to high permeability, its other magnetic properties are low coercivity, near zero magnetostriction, and significant anisotropic magnetoresistance. The low magnetostriction is critical for industrial applications, allowing it to be used in thin films where variable stresses would otherwise cause a ruinously large variation in magnetic properties. Permalloy's electrical resistivity can vary as much as 5% depending on the strength and the direction of an applied magnetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hakaru Masumoto
Hakaru Masumoto (1895–1987) was a pioneer in metal and alloy research. He discovered numerous superior and unique alloys, and contributed to improving the performance of precision machinery. A student of Kotaro Honda, Masumoto developed a magnetic metal powder Sendust in 1936,The Japanese Contributions to the English Language: An Historical Dictionary, by Garland Hampton Cannon, Nicholas W. Warren, page 205 and was the winner of the Imperial Prize of the Japan Academy The is a prestigious honor conferred to two of the recipients of the Japan Academy Prize (academics), Japan Academy Prize. Overviews It is awarded in two categories: humanities and natural sciences. The Emperor of Japan, Emperor and Empress ... in 1946. References {{DEFAULTSORT:Masumoto, Hakaru 1895 births 1987 deaths People from Hiroshima Japanese metallurgists Academic staff of Tohoku University Tohoku University alumni Grand Cordons of the Order of the Rising Sun Recipients of the Orde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Alloys
A magnetic alloy is a combination of various metals from the periodic table such as ferrite that exhibits magnetic properties such as ferromagnetism. Typically the alloy contains one of the three main magnetic elements (which appear on the Bethe-Slater curve): iron (Fe), nickel (Ni), or cobalt (Co). However, alloys such as Heusler alloys exhibit ferromagnetic properties without any of the preceding 3 elements, and alloys of iron and manganese such as stainless steels may be essentially nonmagnetic at room temperature. Magnetic properties of an alloy are highly dependent not only on the composition but also on heat treatment and mechanical processing. Magnetic alloys have become common, especially in the form of steel (iron and carbon), alnico (iron, nickel, cobalt, and aluminum), and permalloy (iron and nickel). So-called "neodymium magnets" are alloys of neodymium, iron and boron forming the crystal structure Nd2Fe14B. After magnetization, items made out of these alloys will r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alperm
Alperm (also alfenol or alfer) is a class of alloys comprising 83-90% of iron and 10-17% of aluminium. The most widely used composition is with 16% Al. An alloy with 13% Al is also sometimes referred to as alfer. It exhibits large magnetostriction and it is used in magnetoelastic sensors. Later during the WW2, Japanese used the alloy with 12.7-12.9% aluminium as a replacement of nickel for the magnetostrictive transducers used in their Type 93 model 5, Type 3, and Simple naval sonars. Alperm is magnetically soft and exhibits high magnetic permeability. The material can be produced in 0.5 mm thick sheets, as well as 50-60 μm thick ribbons. The coercivity is usually below 5 A/m (for alfer it is around 50 A/m) and permeability 55 000 (for alfer 4000). Saturation flux density is 0.8 T (for alfer 1.28 T). The addition of Al increases electrical resistivity of alloy up to 140 μΩm, which is almost four times the value in commonly used 3% SiFe electrical steel. For this rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recording Head
''Tape Head'' is the seventh studio album by American rock band King's X King's X is an American Rock music, rock band formed in Springfield, Missouri, in 1979. They were first called the Edge and later became Sneak Preview before settling on its current name in 1985. The band's current lineup has remained intact fo ..., released in 1998 via Metal Blade Records. A music video was made for the song "Fade". "World" is a reworked song from the band's ''Sneak Preview'' demos. The controversial unreleased track "Quality Control" is included on the album, but has been re-titled to "Happy". The majority of the lyrics are now different, including the lack of profanity. The album cover picture is that of Doug Pinnick wrapped in recording tape. According to Pinnick, he brought the songs "Happy", "Cupid" and "Hate You", and Ty Tabor brought "Ocean" to the ''Tape Head'' recording sessions. All other songs were band created during the recording session. The song "Walter Bela Far ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetocrystalline Anisotropy
In physics, a ferromagnetic material is said to have magnetocrystalline anisotropy if it takes more energy to magnetization, magnetize it in certain directions than in others. These directions are usually related to the crystal structure, principal axes of its crystal lattice. It is a special case of magnetic anisotropy. In other words, the excess energy required to magnetize a specimen in a particular direction over that required to magnetize it along the easy direction is called crystalline anisotropy energy. Causes The spin-orbit interaction is the primary source of magnetocrystalline anisotropy. It is basically the orbital motion of the electrons which couples with crystal electric field giving rise to the first order contribution to magnetocrystalline anisotropy. The second order arises due to the mutual interaction of the magnetic dipoles. This effect is weak compared to the exchange interaction and is difficult to compute from first principles, although some successful co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetostriction
Magnetostriction is a property of magnetic materials that causes them to change their shape or dimensions during the process of magnetization. The variation of materials' magnetization due to the applied magnetic field changes the magnetostrictive strain until reaching its saturation value, λ. The effect was first identified in 1842 by James Joule when observing a sample of iron. Magnetostriction applies to magnetic fields, while electrostriction applies to electric fields. Magnetostriction causes energy loss due to frictional heating in susceptible ferromagnetic cores, and is also responsible for the low-pitched humming sound that can be heard coming from transformers, where alternating currents produce a changing magnetic field. Explanation Internally, ferromagnetic materials have a structure that is divided into '' domains'', each of which is a region of uniform magnetization. When a magnetic field is applied, the boundaries between the domains shift and the domains rota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has a great affinity towards oxygen, passivation (chemistry), forming a protective layer of aluminium oxide, oxide on the surface when exposed to air. It visually resembles silver, both in its color and in its great ability to reflect light. It is soft, magnetism, nonmagnetic, and ductility, ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the abundance of the chemical elements, 12th-most abundant element in the universe. The radioactive decay, radioactivity of aluminium-26, 26Al leads to it being used in radiometric dating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sintered
Sintering or frittage is the process of compacting and forming a solid mass of material by pressure or heat without melting it to the point of liquefaction. Sintering happens as part of a manufacturing process used with metals, ceramics, plastics, and other materials. The atoms/molecules in the sintered material diffuse across the boundaries of the particles, fusing the particles together and creating a solid piece. Since the sintering temperature does not have to reach the melting point of the material, sintering is often chosen as the shaping process for materials with extremely high melting points, such as tungsten and molybdenum. The study of sintering in metallurgical powder-related processes is known as powder metallurgy. An example of sintering can be observed when ice cubes in a glass of water adhere to each other, which is driven by the temperature difference between the water and the ice. Examples of pressure-driven sintering are the compacting of snowfall to a gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tohoku Imperial University
is a public research university in Sendai, Miyagi, Japan. It is colloquially referred to as or . Established in 1907 as the third of the Imperial Universities, after the University of Tokyo and Kyoto University, it initially focused on science and medicine, later expanding to include humanities studies as well. In 2016, Tohoku University had 10 faculties, 16 graduate schools and 6 research institutes, with a total enrollment of 17,885 students. The university's three core values are "Research First (研究第一主義)," "Open-Doors (門戸開放)," and "Practice-Oriented Research and Education (実学尊重)." History On 22 June 1907 (Mēji 40), Tohoku Imperial University (東北帝國大學, Tōhoku teikoku daigaku) was established by the Meiji government as the third Imperial University of Japan, after Tokyo Imperial University (1877) and Kyoto Imperial University (1897). From its inception, it advocated 'Open-door' policies, becoming the first university in Japan to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon
Silicon is a chemical element; it has symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent metalloid (sometimes considered a non-metal) and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, lead, and flerovium are below it. It is relatively unreactive. Silicon is a significant element that is essential for several physiological and metabolic processes in plants. Silicon is widely regarded as the predominant semiconductor material due to its versatile applications in various electrical devices such as transistors, solar cells, integrated circuits, and others. These may be due to its significant band gap, expansive optical transmission range, extensive absorption spectrum, surface roughening, and effective anti-reflection coating. Because of its high chemical affinity for oxygen, it was not until 1823 that Jöns Jakob Berzelius was first able to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
