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Liquidus
The liquidus temperature, TL or Tliq, specifies the temperature above which a material is completely liquid, and the maximum temperature at which crystals can co-exist with the melt in thermodynamic equilibrium. It is mostly used for impure substances (mixtures) such as glasses, alloys and rocks. Above the liquidus temperature the material is homogeneous and liquid at equilibrium. Below the liquidus temperature, more and more crystals will form in the melt if one waits a sufficiently long time, depending on the material. Alternately, homogeneous glasses can be obtained through sufficiently fast cooling, i.e., through kinetic inhibition of the crystallization process. The crystal phase that crystallizes first on cooling a substance to its liquidus temperature is termed primary crystalline phase or primary phase. The composition range within which the primary phase remains constant is known as primary crystalline phase field. The liquidus temperature is important in the glass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solidus (chemistry)
In chemistry, materials science, and physics, the solidus is the locus of temperatures (a curve on a phase diagram) below which a given substance is completely solid (crystallized). The solidus temperature, TS or Tsol, specifies the temperature below which a material is completely solid, and the minimum temperature at which a melt can co-exist with crystals in thermodynamic equilibrium. The solidus is applied, among other materials, to metal alloys, ceramics, and natural rocks and minerals. The solidus quantifies the temperature at which melting of a substance ''begins'', but the substance is not necessarily melted ''completely'', i.e., the solidus is not necessarily a melting point. For this distinction, the solidus may be contrasted to the liquidus. The solidus is always less than or equal to the liquidus, but they need not coincide. If a gap exists between the solidus and liquidus it is called the freezing range, and within that gap, the substance consists of a mixture of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solidus (chemistry)
In chemistry, materials science, and physics, the solidus is the locus of temperatures (a curve on a phase diagram) below which a given substance is completely solid (crystallized). The solidus temperature, TS or Tsol, specifies the temperature below which a material is completely solid, and the minimum temperature at which a melt can co-exist with crystals in thermodynamic equilibrium. The solidus is applied, among other materials, to metal alloys, ceramics, and natural rocks and minerals. The solidus quantifies the temperature at which melting of a substance ''begins'', but the substance is not necessarily melted ''completely'', i.e., the solidus is not necessarily a melting point. For this distinction, the solidus may be contrasted to the liquidus. The solidus is always less than or equal to the liquidus, but they need not coincide. If a gap exists between the solidus and liquidus it is called the freezing range, and within that gap, the substance consists of a mixture of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Diagram
A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions (pressure, temperature, volume, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium. Overview Common components of a phase diagram are ''lines of equilibrium'' or ''phase boundaries'', which refer to lines that mark conditions under which multiple phases can coexist at equilibrium. Phase transitions occur along lines of equilibrium. Metastable phases are not shown in phase diagrams as, despite their common occurrence, they are not equilibrium phases. Triple points are points on phase diagrams where lines of equilibrium intersect. Triple points mark conditions at which three different phases can coexist. For example, the water phase diagram has a triple point corresponding to the single temperature and pressure at which solid, liquid, and gaseous water can coexist in a stab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freezing Point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of substances to supercool, the freezing point can easily appear to be below its actual value. When the "characteristic freezing point" of a substance is determined, in fact, the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice, that is, the melting point." Examples For most substances, melting and freezing points are approximately equal. For example, the melting point ''and'' freezing point of mercury is . How ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, opacity, and luster, but may have properties that differ from those of the pure metals, such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength. Alloys are defined by a metallic bonding character. The alloy constituents are usually measured by mass percentage for practical applications, and in atomic fraction for basic science studies. Alloys are usually classified as substitutional or interstitial alloys, depending on the atomic arrangement that forms the alloy. They can be further classified as homo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutectic System
A eutectic system or eutectic mixture ( ) is a homogeneous mixture that has a melting point lower than those of the constituents. The lowest possible melting point over all of the mixing ratios of the constituents is called the ''eutectic temperature''. On a phase diagram, the eutectic temperature is seen as the eutectic point (see plot on the right). Non-eutectic mixture ratios would have different melting temperatures for their different constituents, since one component's lattice will melt at a lower temperature than the other's. Conversely, as a non-eutectic mixture cools down, each of its components would solidify (form a lattice) at a different temperature, until the entire mass is solid. Not all binary alloys have eutectic points, since the valence electrons of the component species are not always compatible, in any mixing ratio, to form a new type of joint crystal lattice. For example, in the silver-gold system the melt temperature (liquidus) and freeze temperatur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, opacity, and luster, but may have properties that differ from those of the pure metals, such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength. Alloys are defined by a metallic bonding character. The alloy constituents are usually measured by mass percentage for practical applications, and in atomic fraction for basic science studies. Alloys are usually classified as substitutional or interstitial alloys, depending on the atomic arrangement that forms the alloy. They can be further classified as homo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melting Point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of substances to supercool, the freezing point can easily appear to be below its actual value. When the "characteristic freezing point" of a substance is determined, in fact, the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice, that is, the melting point." Examples For most substances, melting and freezing points are approximately equal. For example, the melting point ''and'' freezing point of mercury ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SiO2 Li2O
Sio may refer to: Places * Sió, an artificial channel in Hungary * Siø, a small Danish island in the South Funen Archipelago * Sio, Burkina Faso, a village in Burkina Faso * Sio, Mali, a commune in Mali * Sio, Papua New Guinea, a town in Papua New Guinea * Sio, a river in Western Africa providing water for the Lake Togo * Smithton Airport (IATA airport code), Tasmania, Australia Computing * SIO (software), a serial port driver for the OS/2 operating system * Atari SIO, a peripheral bus * Super I/O, a motherboard chipset component Organizations * Scripps Institution of Oceanography, La Jolla, California, U.S. * Students Islamic Organisation of India * Foundation for Student Life in Oslo (''Studentsamskipnaden i Oslo'') * '' Sexarbejdernes Interesse Organisation'', a Nordic organization of sex workers (see Prostitution in Sweden) People * Sio (cartoonist), Italian comics artist * William Sio (born 1960), New Zealand politician * David Sio (born 1962), Samoan r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgy
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals; that is, the way in which science is applied to the production of metals, and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist. The science of metallurgy is further subdivided into two broad categories: chemical metallurgy and physical metallurgy. Chemical metallurgy is chiefly concerned with the reduction and oxidation of metals, and the chemical performance of metals. Subjects of study in chemical metallurgy include m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Physics
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material. Despite be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
