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Materials & Crystals合金合金，就是两种或两种以上化学物质（至少有一组分为金属）混合而成具有金属特性的物质，一般由各组分熔合成均匀的液体，再经冷凝而得。 合金至少是以下三种中的一种：元素形成的单一相固态溶液，许多金属相形成的混合物，金属形成的金属互化物。固态溶液的合金其微观结构有单一相，部分为溶液的合金则是有二相或二相以上，其分布可能是均匀，也可能不均匀，依材料冷却过程的温度变化而定。金属互化物一般会有一种合金或纯金属包在另一种纯金属内。 由于合金一些特性比纯金属元素要好，因此会用在特定的应用中。合金的例子包括钢、焊料、黄铜、白镴、磷青铜及汞齐等。 合金的成分一般是以质量比例来计算。合金依其原子组成的方式，可以区分为替代合金或间质合金，又可以进一步区分为匀相（只有一相）、非匀相（不止一相）及金属互化物（两相之间没有明显的边界）。
An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although the word is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and copper. In an alloy, the atoms are joined by metallic bonding rather than by covalent bonds typically found in chemical compounds. 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.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 相图（英语：Phase diagram），也称相态图、相平衡状态图，是用来表示相平衡系统的组成与一些参数（如温度、压力）之间关系的一种图。它在物理化学、矿物学和材料科学中具有很重要的地位。
A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions (pressure, temperature, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium.
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View content license ↗ 共晶系统或共熔系统（英语：eutectic system），冶金学名词，是指两个不同化学物质或元素，在以某一特定比例混合后，能够在比各自熔点还要低的温度下，进行加热熔合，形成均匀的混合物（mixture）。用来形成共晶系统的混合物被称为共晶混合物或共熔混合物（eutectic mixture），形成的化合物被称为共晶组成物或共熔组成物（eutectic composition），而这个熔合温度则称为共晶温度或共熔温度（eutectic temperature）。 在相图上定义共晶点的坐标是共晶百分比（在图的原子/分子比轴上）和共晶温度（在图的温度轴上）。 在相图上，共晶温度与共晶组成这两者的交界，形成了共晶点或共熔点（eutectic point）。但不是所有的二元合金都拥有共晶点，例如，银－金混合系统，它的熔化温度液相线（liquidus）与凝固温度固相线（Solidus），比起纯银跟纯金都还要高。 若将该系统在"共晶浓度"时由液态开始降温，当降温通过"共晶温度"时便会发生物质直接由液态转变为α、β两种固态物质的反应，即为"共晶反应"。共晶反应发生时必将伴随原子的重新分配而形成α与β相交杂的层状结构 ( lamellae ) 。由液态转变为固态之α与β相时，液态物质中的原子会有扩散至同种原子占比较丰富的那一个相态之倾向；又因为扩散作用发生的时间极短，故原子仅能扩散一小段距离，因而形成交错的层状结构。 若所选取的浓度在降温过程中不会经过共晶点，而是由 ( L + α ) 态或 ( L + β ) 态转变为 ( α + β ) 态，则原先便已长出的晶粒称为 ( primary )，而当温度达到共晶温度时才长出的晶粒则称为 ( eutectic )。由共晶反应所长出之层状结构中的 eutectic 和先前长出的 primary 虽然化学组成相同，但因 eutectic 和 primary 在结构上有所区别，因此eutectic 和 primary 为两种不同的"微成分 ( microconstituent ) "。 另外两种类似而发生在多物质相图的反应分别为"共析反应 ( Eutectoid ) " 和 "包晶反应 ( peritectic ) "。 共析反应系由一固相态经由冷却或升温转变为另外两种不同的固相态晶粒。 包晶反应则为一固态相经由冷却或升温转变为一液态相和另外一种固态相晶粒。
A eutectic system or eutectic mixture ( yoo-TEK-tik) is a type of 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). Non-eutectic mixture ratios 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 solidifies into a lattice at a different temperature, until the entire mass is solid. A non-eutectic mixture thus does not have a single melting/freezing point temperature at which it changes phase, but rather a temperature at which it changes between liquid and slush (known as the liquidus) and a lower temperature at which it changes between slush and solid (the solidus).
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 在热力学中，某种物质的化学势指的是，在化学反应或者相变中，此物质的粒子数发生改变时所吸收或放出的能量。在混合物中的某种物质的化学势定义为此热力学系统的吉布斯自由能对此物质粒子数的变化率，即偏导数（其他物质的粒子数及其他系统参数保持不变）。当温度和压强固定时，化学势也被称作偏摩尔吉布斯自由能，或者摩尔化学势。在化学平衡或相平衡状态下，自由能处于极小值，各种物质的化学势与化学计量系数乘积之和为零。 在半导体物理中，零温电子系统的化学势被称为费米能。
In thermodynamics, the chemical potential of a species is the energy that can be absorbed or released due to a change of the particle number of the given species, e.g. in a chemical reaction or phase transition. The chemical potential of a species in a mixture is defined as the rate of change of free energy of a thermodynamic system with respect to the change in the number of atoms or molecules of the species that are added to the system. Thus, it is the partial derivative of the free energy with respect to the amount of the species, all other species' concentrations in the mixture remaining constant. When both temperature and pressure are held constant, and the number of particles is expressed in moles, the chemical potential is the partial molar Gibbs free energy. At chemical equilibrium or in phase equilibrium, the total sum of the product of chemical potentials and stoichiometric coefficients is zero, as the free energy is at a minimum. In a system in diffusion equilibrium, the chemical potential of any chemical species is uniformly the same everywhere throughout the system.
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View content license ↗ 吉布斯相律是由约西亚·吉布斯于19世纪70年代提出的一个公式，说明了在特定相态下，系统的自由度跟其他变量的关系。它是相图的基本原理。 吉布斯相律的表达式为： F = C − P + n {\displaystyle F\;=\;C\;-\;P\;+\;n} 式中， F {\displaystyle F} （或作 π {\displaystyle \pi } ，Φ），表示系统的自由度， C ：系统的独立组元数（number of independent component） P ：相态数目 n ：外界因素，多数取n=2，代表压力和温度；对于熔点极高的固体，蒸汽压的影响非常小，可取n=1。
In thermodynamics, the phase rule is a general principle governing multi-component, multi-phase systems in thermodynamic equilibrium. For a system without chemical reactions, it relates the number of freely varying intensive properties (F) to the number of components (C), the number of phases (P), and number of ways of performing work on the system (N): F = N + C − P + 1 {\displaystyle F=N+C-P+1} Examples of intensive properties that count toward F are the temperature and pressure. For simple liquids and gases, pressure-volume work is the only type of work, in which case N = 1. The rule was derived by American physicist Josiah Willard Gibbs in his landmark paper titled On the Equilibrium of Heterogeneous Substances, published in parts between 1875 and 1878.
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View content license ↗ 位错（英语：dislocation），在材料科学中，指晶体材料的一种内部微观缺陷，即原子的局部不规则排列（晶体缺陷）。从几何角度看，位错属于一种线缺陷，可视为晶体中已滑移部分与未滑移部分的分界线，其存在对材料的物理性能，尤其是力学性能，具有极大的影响。“位错”这一概念最早由意大利数学家和物理学家维托·伏尔特拉于1905年提出。 理想位错主要有三种形式：刃位错（edge dislocation）和 螺旋位错（screw dislocation）及混合位错（mixed dislocation）兼有前面两者的特征。 数学上，位错属于一种拓扑缺陷，有时称为“孤立子”或“孤子”。这一理论可以解释实际晶体中位错的行为：可以在晶体中移动位置，但自身的种类和特征在移动中保持不变；方向（伯格斯矢量）相反的两个位错移动到同一点，则会双双消失，或称“湮灭”，若没有与其他位错发生作用或移到晶体表面，那么任何单个位错都不会自行“消失”（即伯格斯矢量始终保持守恒）。
In materials science, a dislocation is a linear crystallographic defect or irregularity within a crystal structure that contains an abrupt change in the arrangement of atoms. The movement of dislocations allows atoms to slide over each other at low stress levels and is known as glide or slip. The crystalline order is restored on either side of a glide dislocation but the atoms on one side have moved by one position. The crystalline order is not fully restored with a partial dislocation. A dislocation defines the boundary between slipped and unslipped regions of material and as a result, must either form a complete loop, intersect other dislocations or defects, or extend to the edges of the crystal. A dislocation can be characterised by the distance and direction of movement it causes to atoms which is defined by the Burgers vector. Plastic deformation of a material occurs by the creation and movement of many dislocations. The number and arrangement of dislocations influences many of the properties of materials.
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View content license ↗ 晶粒边界（英语：grain boundary），简称晶界，指多晶材料中晶粒之间的接合区域。在结晶学中晶粒边界是一种二维的晶体缺陷。晶粒边界出现在结构相同方向不同的微晶区域里，通过化学腐蚀可以使之在晶体表面显现。晶粒边界有小角度晶界和大角度晶界之分。当两个微晶区域之间的角度差值大于15度时，我们称之为大角度晶界。大角度晶界阻碍了位错的形成，从而影响了相邻晶粒。因此大角度晶界对金属材料的机械特性影响显著。在大多数情况下，晶粒边界会导致强度的提高，也就是说细粒度晶体更加坚固，但是析出物（特别是在容易在晶粒边界聚集的氧化物）同时也会削弱晶体强度。
In materials science, a grain boundary is the interface between two differently oriented grains, or crystallites, of the same phase in a polycrystalline material. Grain boundaries are two-dimensional defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material. Most grain boundaries are preferred sites for the onset of corrosion and for the precipitation of new phases from the solid. They are also important to many of the mechanisms of creep. On the other hand, grain boundaries disrupt the motion of dislocations through a material, so reducing crystallite size is a common way to improve mechanical strength, as described by the Hall–Petch relationship.
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View content license ↗ 成核（英语：Nucleation，也称形核、核化）是相变初始时的“孕育阶段”。天空中的云、雾、雨，燃烧生成的烟，冰的结晶，汽水、啤酒的冒出的泡等的形成，均为成核现象。 成核现象需要成核位点（nucleation site）才可发生。汽化时，液相分子聚集于固相物质上面，分子不断碰撞使得能量聚集，进而形成“汽化中心”；结晶时，若使局部的溶质浓度升高而导致晶体碰撞次数增加，则结晶的晶形构造加快，从而形成“结晶中心”。晶核（英语：crystal nucleus）为晶体的生长中心。晶核的成核有两种形式：初级成核（包括初级均相成核和初级非均相成核）及二次成核。在高于饱和度的情况下，溶液自发形成晶核的过程，称作初级均相成核；若晶核是在溶液外来物的诱导下生成，则称其为初级非均相成核；晶核如在含有溶质晶体的溶液中生成，则称为二次成核。
In thermodynamics, nucleation is the first step in the formation of either a new thermodynamic phase or structure via self-assembly or self-organisation within a substance or mixture. Nucleation is typically defined as the process that determines how long an observer must wait before a new phase or self-organised structure appears. For example, if a volume of water is cooled (at atmospheric pressure) significantly below 0 °C, it will tend to freeze into ice. Still, volumes of water cooled only a few degrees below 0 °C often stay completely free of ice for long periods (supercooling). Under these conditions, nucleation of ice is either slow or does not occur at all. However, at lower temperatures nucleation is fast, and ice crystals appear after little or no delay. Nucleation is a common mechanism which generates first-order phase transitions, and it is the start of the process of forming a new thermodynamic phase. In contrast, new phases at continuous phase transitions start to form immediately. Nucleation is often very sensitive to impurities in the system.
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View content license ↗ 固溶体是指溶质原子溶入溶剂晶格中而仍保持溶剂类型的合金相。通常以一种化学物质为基体溶有其他物质的原子或分子所组成的晶体，在合金和硅酸盐系统中较多见，在多原子物质中亦存在。 当溶剂的晶体结构添加溶质后可以稳定存在且保持均相，则该种混合物可以被视作溶液。 一些混合物可以在很多种浓度情况下形成固溶体，而有一些混合物根本不能形成固溶体。两种物质混合而形成固溶体的倾向是一个复杂的事情，涉及化学、晶体学及量子物理学。
A solid solution, a term commonly used for metals, is a homogeneous mixture of two compounds in solid state and having a single crystal structure. Many examples can be found in metallurgy, geology, and solid-state chemistry. The word "solution" is used to describe the intimate mixing of components at the atomic level and distinguishes these homogeneous materials from physical mixtures of components. Two terms are mainly associated with solid solutions – solvents and solutes, depending on the relative abundance of the atomic species. The solute may incorporate into the solvent crystal lattice substitutionally, by replacing a solvent particle in the lattice, or interstitially, by fitting into the space between solvent particles. Solid solutions consist of fractional composition of one or more of its constituent ions between pure, isostructural extremes, known as end members or parents.
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View content license ↗ 配位化学中，配位数（Coordination number）指化合物中中心原子周围的配位原子个数，此概念首先由阿尔弗雷德·维尔纳在1893年提出。 配位数通常为2-8，也有高达10以上的，如铀和钍的双齿簇状硝酸根离子U(NO3)62−、Th(NO3)62−，及2007年研究的PbHe152+离子（铅的配位数至少为15），2015年研究的CoB16−（配位数为16）。 此概念也可延伸至任何化合物，也就是配位数等同于共价键键连数，例如，可以说甲烷中碳的配位数为4。这种说法通常不计π键。 晶体学中，配位数是晶格中与某一原子相距最近的原子个数。配位数与晶体结构或晶胞类型有关，且决定原子堆积的紧密程度，体心立方堆积中原子配位数为8。最高的配位数为12，存在于六角密堆和面心立方结构中。
In chemistry, crystallography, and materials science, the coordination number, also called ligancy, of a central atom in a molecule or crystal is the number of atoms, molecules or ions bonded to it. The ion/molecule/atom surrounding the central ion/molecule/atom is called a ligand. This number is determined somewhat differently for molecules than for crystals. For molecules and polyatomic ions the coordination number of an atom is determined by simply counting the other atoms to which it is bonded (by either single or multiple bonds). For example, [Cr(NH3)2Cl2Br2]− has Cr3+ as its central cation, which has a coordination number of 6 and is described as hexacoordinate. The common coordination numbers are 4, 6 and 8.
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View content license ↗ 杠杆原理（英语：Lever rule）又称杠杆定律。是一个用来计算相图中各相的组成比例的方式。 在一个有两个不同的相，α 与 β，的溶液中，其组成成分为A，B，由杠杆原理可得该溶液α相的比例为： X α = c − b a − b {\displaystyle X_{\alpha }={\frac {c-b}{a-b}}} 其中 a为B在α相中的摩尔分率。 b为B在β相中的摩尔分率。 c为B在溶液所有相态中的总摩尔分率。 上式适用于定温的情况。
In chemistry, the lever rule is a formula used to determine the mole fraction (xi) or the mass fraction (wi) of each phase of a binary equilibrium phase diagram. It can be used to determine the fraction of liquid and solid phases for a given binary composition and temperature that is between the liquidus and solidus line.
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View content license ↗ 阴极射线发光（Cathodoluminescence，CL）或阴极发光、阴极射线致发光，是一种冷发光现象，指的是磷光体之类的材料受电子照射时发射出可见光的现象。阴极射线发光常见于老式电视的显像管；其利用电子束在电视屏幕内侧的磷光体上来回扫描，通过控制屏幕上不同区域的发光强度生成图像。
Cathodoluminescence is an optical and electromagnetic phenomenon in which electrons impacting on a luminescent material such as a phosphor, cause the emission of photons which may have wavelengths in the visible spectrum. A familiar example is the generation of light by an electron beam scanning the phosphor-coated inner surface of the screen of a television that uses a cathode-ray tube. Cathodoluminescence is the inverse of the photoelectric effect, in which electron emission is induced by irradiation with photons.
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View content license ↗ 挫屈（buckling）力学称屈曲 ，土木工程称为挫屈；是指细长杆件受到压力时，发生弯曲变形的一种现象。由不稳定造成的结构失效称为屈曲失效。理想压杆丧失稳定后，由原来的直线平衡状态变为弯曲平衡状态。理论上，挫曲是因为力学平衡方程式的解出现分岔（解的本质发生改变）所造成的。在受力增加到一定程度之后，物体会出现二种平衡状态，一种是纯压缩力，另一个是有侧向偏移变形的平衡状态。 挫屈的特点是在结构件中，边缘承受压缩应力的元件突然断裂，而元件失效时的压应力小于材料可以承受的终极抗压应力。挫曲的数学分析一般会设法加入方向也是轴向，但和轴有一段位移（偏心）的压应力，以产生原来理想施力时不会受现的二次弯矩。 当在一元件（例如杆件）上的压缩负荷增加，多半最后负荷会大到使元件变形不稳定。若负荷继续加大，会造成明显，甚至无法预测的变形，可能让元件完全无法承受负荷。若变形还不是灾难性的，元件仍会继续承受负载。若挫曲的元件是结构件（例如大楼）中的一部分，会由其他的元件来分担已挫曲元件原来要承受的负载。
In structural engineering, buckling is the sudden change in shape (deformation) of a structural component under load, such as the bowing of a column under compression or the wrinkling of a plate under shear. If a structure is subjected to a gradually increasing load, when the load reaches a critical level, a member may suddenly change shape and the structure and component is said to have buckled. Euler's critical load and Johnson's parabolic formula are used to determine the buckling stress of a column. Buckling may occur even though the stresses that develop in the structure are well below those needed to cause failure in the material of which the structure is composed. Further loading may cause significant and somewhat unpredictable deformations, possibly leading to complete loss of the member's load-carrying capacity. However, if the deformations that occur after buckling do not cause the complete collapse of that member, the member will continue to support the load that caused it to buckle.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 脆性（英语：brittleness），是指物质受力时未有明显塑性变形就断裂的性质。脆性是和延展性相反的概念。脆性物质即使强度很高，发生脆性断裂前，也只能吸收较少能量。常见的脆性物质有陶瓷和玻璃等。脆性物质失效的主要机理为脆性断裂，是构件未经明显的变形而发生的断裂。
A material is brittle if, when subjected to stress, it fractures with little elastic deformation and without significant plastic deformation. Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a sharp snapping sound. When used in materials science, it is generally applied to materials that fail when there is little or no plastic deformation before failure. One proof is to match the broken halves, which should fit exactly since no plastic deformation has occurred.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 陶瓷工程是使用无机非金属材料制造物体的科学技术。陶瓷工程的研究范围包括包括对原材料的提纯、对需要的化学成分的研究和生产以及对产物的结构、成分和性质的研究。 陶瓷材料可能含有全部或者部分的晶体结构，在原子层面上是大范围有序的。玻璃陶瓷可能有不定型或类似玻璃的结构，几乎没有有序度或者只能小范围有序。他们的制造方法可能通过是熔化物质冷却凝固，通过加热、或者在低温下通过化学手段如水热或溶胶凝胶法得到。 陶瓷材料特性使其能够在材料工程、电子工程、化学工程以及机械工程中得到很多应用。由于通常陶瓷非常耐热，他们可以用于很多金属和聚合物无法胜任的地方。陶瓷材料在工业中有广泛的应用，包括采矿、航天、医药、精炼、军事、食品和化学工厂、电子行业、工业输电、以及光波导传输等等。
Ceramic engineering is the science of creating objects from inorganic, non-metallic materials. This is done using either heat or precipitation reactions on high-purity chemical solutions at lower temperatures. The term includes the purification of raw materials, the study and production of chemical compounds, their formation into components, and the study of their structure, composition, and properties. Ceramic materials may have a crystalline or partly crystalline structure, with long-range order on atomic scale. Glass-ceramics may have an amorphous or glassy structure. They can be formed from a molten mass that solidifies on cooling or chemically synthesized at low temperatures using methods such as hydrothermal synthesis. Ceramic materials are used in the fields of materials engineering, electrical engineering, chemical engineering and mechanical engineering. Ceramics are heat resistant, so they can be used for tasks in which materials like metal and polymers are unsuitable.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 在材料科学中，伯格斯矢量（Burgers vector，得名于荷兰物理学家扬·伯格斯）是一个向量（通常记作b），用于表示晶体结构中位错引起的晶格畸变的大小和方向。
In materials science, the Burgers vector, named after Dutch physicist Jan Burgers, is a vector, often denoted as b, that represents the magnitude and direction of the lattice distortion resulting from a dislocation in a crystal lattice.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 固体中的键结可依其原子或分子间的化学键键结型态进行分类。传统上分为以下四种键结： 共价键，形成共价网状固体（有时简称“共价固体”）者 离子键，形成离子固体者 金属键，形成金属固体者 分子间作用力，形成分子晶体（有时亦称“共价固体”）者 这些分类的成员含有不同的电荷分布、 热力、电子、以及力学性质。各类型的键能大小差异极大。而由于固体中的键结可以是混合的或是介于上述的分类之间，所以并非所有固体都是具有特定某种分类的性质，因此有些固体会被称为中间型态固体。
Solids can be classified according to the nature of the bonding between their atomic or molecular components. The traditional classification distinguishes four kinds of bonding: Covalent bonding, which forms network covalent solids (sometimes called simply "covalent solids") Ionic bonding, which forms ionic solids Metallic bonding, which forms metallic solids Weak inter molecular bonding, which forms molecular solids (sometimes anomalously called "covalent solids") Typical members of these classes have distinctive electron distributions, thermodynamic, electronic, and mechanical properties. In particular, the binding energies of these interactions vary widely. Bonding in solids can be of mixed or intermediate kinds, however, hence not all solids have the typical properties of a particular class, and some can be described as intermediate forms.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 凝聚态物理学（condensed matter physics）又称凝态物理学、凝（聚）体物理学等，是研究物质凝聚态（固态和液态）或凝聚相的物理本质、结构和性质的一门学科，为固体物理学的延拓。该领域的研究者力图通过物理学定律来解释凝聚相物质的行为。其中，量子力学、电磁学以及统计力学的相关定律对于该领域尤为重要。 凝（聚）态（condensed state）或凝（聚）相（condensed phase）是由大量粒子组成，且粒子间有很强相互作用的系统。固相以及液相是人们最为熟悉的凝聚相，由于两者通常体积固定，不似气相具有可压缩性，故称之为凝（聚）相。除了这两种相之外，凝聚相还包括一些特定的物质在低温条件下的超导相、自旋有关的铁磁相及反铁磁相、超低温原子系统的玻色-爱因斯坦凝聚相等等。对于凝聚态的研究包括通过实验手段测定物质的各种性质，以及利用理论方法发展数学模型以深入理解这些物质的物理行为。 由于尚有大量的系统及现象亟待研究，凝聚态物理学成为了目前物理学最为活跃的领域之一。仅在美国，该领域的研究者就占到该国物理学者整体的近三分之一，凝聚态物理学部也是美国物理学会最大的部门。此外，该领域还与化学，材料科学以及纳米技术等学科领域交叉，并与原子物理学以及生物物理学等物理学分支紧密相关。该领域研究者在理论研究中所采用的一些概念与方法也适用于粒子物理学及核物理学等领域。 晶体学、冶金学、弹性力学以及磁学等等起初是各自独立的学科领域。这些学科在二十世纪四十年代被物理学家统合为固体物理学。时间进入二十世纪六十年代后，有关液体物理性质的研究也被纳入其中，形成凝聚态物理学这一新学科。据物理学家菲利普·安德森所述，术语“凝聚态物理学”是他和福尔克尔·海涅首创。1967年，他们把位于卡文迪许实验室的研究组名称由“固体理论”改为“凝聚态理论”。二人觉得原来的名称并没有涵盖液体及核物质等方面研究。但是，“凝聚态”这一术语此前已在欧洲学界出现，只是由他们普及而已。较为著名的例子是施普林格公司于1963年创建的期刊《凝聚态物理学》（英语：Physics of Condensed Matter）。二十世纪六、七十年代的资金环境以及各国政府采取的冷战政策促使相关领域物理学家接纳了“凝聚态物理学”这一术语。他们认为这一术语相对于“固体物理学”而言更为突出了固体、液体、等离子体以及其他复杂物质研究之间的共通性。这些研究与金属和半导体在工业上的应用息息相关。贝尔实验室是最早开展凝聚态物理学研究项目的研究机构之一。
Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases, that arise from electromagnetic forces between atoms and electrons. More generally, the subject deals with condensed phases of matter: systems of many constituents with strong interactions among them. More exotic condensed phases include the superconducting phase exhibited by certain materials at extremely low cryogenic temperatures, the ferromagnetic and antiferromagnetic phases of spins on crystal lattices of atoms, the Bose–Einstein condensates found in ultracold atomic systems, and liquid crystals. Condensed matter physicists seek to understand the behavior of these phases by experiments to measure various material properties, and by applying the physical laws of quantum mechanics, electromagnetism, statistical mechanics, and other physics theories to develop mathematical models and predict the properties of very large groups of atoms.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 组合化学是一种在短时间内，以有限的反应步骤，同步合成大量具有相同结构母核化合物的技术。组合化学兴起于1990年代，是在固相多肽合成技术的基础上发展而成的，在药物先导化合物的发现和优化、免疫学研究、新材料开发等领域有着广泛的应用。在1990年代后期，组合化学曾经风靡一时，甚至有学者认为，有了组合化学方法，人类可以穷尽所有可能的化合物，并从中获得所有能够成为药物的分子，耗时耗力有目标的药物设计方法将成为历史。但是进入2000年后，人们渐渐意识到，依靠组合化学方法也不可能穷尽所有化合物，组合化学方法逐渐与合理药物设计相结合，成为现代药物研究的重要方法之一。
Combinatorial chemistry comprises chemical synthetic methods that make it possible to prepare a large number (tens to thousands or even millions) of compounds in a single process. These compound libraries can be made as mixtures, sets of individual compounds or chemical structures generated by computer software. Combinatorial chemistry can be used for the synthesis of small molecules and for peptides. Strategies that allow identification of useful components of the libraries are also part of combinatorial chemistry. The methods used in combinatorial chemistry are applied of outside chemistry as well.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 抗压强度（英语：Compressive strength）为指定材料抵抗以同一轴线施加压力的能力，当压力超越抗压强度时，材料会出现脆断、塑性变形等不可逆的形变。混凝土的抗压强度可以超过50MPa（百万帕斯卡），但塑胶容器的抗压强度可以低于250N。 它与抗拉强度、剪切强度等都是评核材料强度的标准，对结构的设计很有帮助。材料的抗压强度并不一定与其抗拉强度等相若。陶瓷、混凝土的抗压强度高于抗拉强度；而复合材料的抗拉强度则倾向高于抗压强度。金属的抗压及抗拉强度较难比较，其在受压时可能会屈曲、碎裂或被剪切，在拉扯时会持续变幼或在其弱点断裂。 材料的抗压强度可以用万能材料试验机测量，这种机器小至可放于桌上、大至可产生53MN（百万牛顿）的力量。测量抗压强度有一定的方法和条件规限，并以既定的标准记录。
In mechanics, compressive strength (or compression strength) is the capacity of a material or structure to withstand loads tending to reduce size (compression). It is opposed to tensile strength, which withstands loads tending to elongate, resisting tension (being pulled apart). In the study of strength of materials, compressive strength, tensile strength, and shear strength can be analyzed independently. Some materials fracture at their compressive strength limit; others deform irreversibly, so a given amount of deformation may be considered as the limit for compressive load. Compressive strength is a key value for design of structures. Compressive strength is often measured on a universal testing machine. Measurements of compressive strength are affected by the specific test method and conditions of measurement. Compressive strengths are usually reported in relationship to a specific technical standard.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 压应力（Compressive stress）是物体受到向内挤压的力时所产生的应力。压应力会在物体被挤压，长度缩短时出现。日常生活常有压应力的例子，例如大楼的重量会对墙以及其基础产生压应力，当人站着的时候。腿部骨骼会因为身体的重量而产生压应力。若压应力够大，会使得受压物体变形甚至破裂。材料可承受，不会损坏的最大压应力即为抗压强度。 压应力 = -( F/A) 其中 F是物体所受到的力 A是物体的截面积 压应力的数值一般会是负值，表示物体受到挤压，受力方向和面积的对外法方量方向相反，不过在土力工程中，压应力会以正值表示。 物体所受的压应力若超过抗压强度，物体会产生脆断、塑性变形等不可逆的形变。不过针对细长形的结构件，虽然压应力未达到抗压强度，也可能因为挫曲而产生结构失效。
Compressive stresses are generated in objects when they are subjected to forces that push inward, causing the material to shorten or compress. These stresses occur when an object is squeezed or pressed from opposite directions. In everyday life, compressive stresses are common in many structures and materials. For instance, the weight of a building creates compressive stresses in its walls and foundations. Similarly, when a person stands, the bones in their legs experience compressive stresses due to the weight of the body pushing down. Compressive stresses can lead to deformation if they are strong enough, potentially causing the object to change shape or, in extreme cases, to break. The ability of a material to withstand compressive stresses without failing is known as its compressive strength. When an object is subjected to a force in a single direction (referred to as a uniaxial compression), the compressive stress is determined by dividing the applied force by the cross-sectional area of the object. Consequently, compressive stress is expressed in units of force per unit area.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 库仑爆炸是从强电磁场耦合电子激发能到原子运动的一种现象。有着相同电荷的粒子的库仑斥力可以断裂维持固体的键（力）。当窄激光束照射上去时，小量的金属爆炸为被电离的原子微粒等离子体。与热的烧蚀不同，库仑爆炸是“冷”的——在热量传导到足够远时，爆炸已完成了。 库仑爆炸的蚀刻可以被用于任何材料来钻孔、去除表面层和表面结构化、表面微构化，如在打印过程中控制墨水的加载。 高速摄像机拍下了碱金属在水中爆炸的过程，它被认为是库仑爆炸。
A Coulombic explosion is a condensed-matter physics process in which a molecule or crystal lattice is destroyed by the Coulombic repulsion between its constituent atoms. Coulombic explosions are a prominent technique in laser-based machining, and appear naturally in certain high-energy reactions.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 镀膜是一种将特定材料披覆于另一材料的方法，以达到特定的目的，属于表面处理的一种。例如提高硬度、耐酸碱、化学盾性、光穿透性等。镀膜技术常运用于光电、半导体、水五金、光学、生医等产业；常见应用为汽车镀膜、居家镀膜、皮革镀膜。
A coating is a covering that is applied to the surface of an object, or substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids, e.g., powder coatings. Paints and lacquers are coatings that mostly have dual uses, which are protecting the substrate and being decorative, although some artists paints are only for decoration, and the paint on large industrial pipes is for identification, e.g., blue for process water, red for fire-fighting control) in addition to preventing corrosion. Along with corrosion resistance, functional coatings may also be applied to change the surface properties of the substrate, such as adhesion, wettability, or wear resistance. In other cases the coating adds a completely new property, such as a magnetic response or electrical conductivity, as in semiconductor device fabrication, where the substrate is a wafer, and forms an essential part of the finished product. A major consideration for most coating processes is controlling coating thickness.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 杂质是材料科学和化学领域的概念，是指有限量的液体、气体或固体内所含有的其他少量化学物质。杂质这个概念与材料或化合物的化学成分概念不同。 杂质要么是天然存在的，要么是在化学合成时添加进去的。在产品生产过程中，人们可能会有意或无意地将杂质添加到产品当中。有很多机构制定了标准，特地规定产品中的杂质含量上限。
In chemistry and materials science, impurities are chemical substances inside a confined amount of liquid, gas, or solid. They differ from the chemical composition of the material or compound. Firstly, a pure chemical should appear in at least one chemical phase and can also be characterized by its phase diagram. Secondly, a pure chemical should prove to be homogeneous (i.e., a uniform substance that has the same composition throughout the material). The perfect pure chemical will pass all attempts to separate and purify it further. Thirdly, and here we focus on the common chemical definition, it should not contain any trace of any other kind of chemical species. In reality, there are no absolutely 100% pure chemical compounds, as there is always some small amount of contamination. The levels of impurities in a material are generally defined in relative terms. Standards have been established by various organizations that attempt to define the permitted levels of various impurities in a manufactured product.
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View content license ↗ 表征（英语：characterization）又称示性、特征化、特性化、表征分析，作为化学及材料科学的术语，指用物理或化学方法对物质进行化学性质的分析、测试或鉴定，并阐明物质的化学特性。此概念包括很多具体手段，包括各种显微技术、紫外-可见-红外光谱、衍射、电子光谱、质谱等；所表征的特性包括元素组成（化学成分）、元素的化学环境（成键情况）、材料的晶体结构、材料的表面形态等。 在生物学、医学中，表征又称（特征）描述、特性分析，是对复杂系统或过程最具特征的性状，进行识别和表征的过程。
Characterization in materials science is the broad and general process by which a material's structure and properties are probed and measured. It is a fundamental process in the field of materials science, without which no scientific understanding of engineering materials could be ascertained. The scope of the term often differs; some definitions limit the term's use to techniques which study the microscopic structure and properties of materials, while others use the term to refer to any materials analysis process including macroscopic techniques such as mechanical testing, thermal analysis and density calculation. The scale of the structures observed in materials characterization ranges from angstroms, such as in the imaging of individual atoms and chemical bonds, up to centimeters, such as in the imaging of coarse grain structures in metals. While many characterization techniques have been practiced for centuries, such as basic optical microscopy, new techniques and methodologies are constantly emerging.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 接触电阻简称ECR，是因为两个表面不完整接触，电流流过产生的电阻，也有可能是表面的薄膜或是氧化层所导致。接触电阻会出现在电接点上，像是开关、连接器、断路器或是量测设备上。接触电阻一般很小（几个毫欧姆到几个微欧姆的大小）。 在高电流下，接触电阻可能会产生显著的电压降，并且发热。因为接触电阻的效果会和导体的内阻叠加，因此若需要用到确切的电阻值，可能会因为接触产生显著的误差。 接触电阻会随温度变化，也会随时间变化（一般是减少），这称为是电阻潜变（resistance creep）。 接触电阻也称为界面电阻（interface resistance）、过渡电阻（transitional resistance）或修正项（correction term）。更通用的说法是杂散电阻（Parasitic resistance），其中接触电阻可能是主要成分之一。 威廉·肖克利引入了injection电极中电位降的概念，说明渐近通道近似和实验结果之间的误差。
Electrical contact resistance (ECR, or simply contact resistance) is resistance to the flow of electric current caused by incomplete contact of the surfaces through which the current is flowing, and by films or oxide layers on the contacting surfaces. It occurs at electrical connections such as switches, connectors, breakers, contacts, and measurement probes. Contact resistance values are typically small (in the microohm to milliohm range). Contact resistance can cause significant voltage drops and heating in circuits with high current. Because contact resistance adds to the intrinsic resistance of the conductors, it can cause significant measurement errors when exact resistance values are needed. Contact resistance may vary with temperature. It may also vary with time (most often decreasing) in a process known as resistance creep. Electrical contact resistance is also called interface resistance, transitional resistance, or the correction term. Parasitic resistance is a more general term, of which it is usually assumed that contact resistance is a major component.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 化合物熔化形成的液体与固体成分相同时，就会发生一致熔融，与不一致熔融相对。一致熔融通常发生于双组分体系。一般情况下，设A和B是两种组分，AB是由它们化学结合形成的稳定固体化合物。画出系统相图，则有三个固相，即A、B和化合物AB。相应地，这三个固相有三个熔点或冰点曲线AC、BE和CDE。相图中顶点D是化合物AB的熔点，因为此时固相和液相组成相同。在这个温度下，由于固、液相均只含有化合物AB，双组分体系变成了单组分体系。 一致熔融点代表确定的温度，就像纯组分的熔点一样。在相图中，化合物AB的熔点D高于纯组分A和B的熔点，但这并不一定正确。在已知不同类型的体系中，一致熔融点小于纯组分的熔点。 这种情况发生于金属间化合物，如MgSi2。
Congruent melting occurs during melting of a compound when the composition of the liquid that forms is the same as the composition of the solid. It can be contrasted with incongruent melting. This generally happens in two-component systems. To take a general case, let A and B be the two components and AB a stable solid compound formed by their chemical combination. If we draw a phase diagram for the system, we notice that there are three solid phases, namely A, B and compound AB. Accordingly, there will be three fusion or freezing point curves AC, BE and CDE for the three solid phases. In the phase diagram, we can notice that the top point D of the phase diagram is the congruent melting point of the compound AB because the solid and liquid phases now have the same composition. Evidently, at this temperature, the two-component system has become a one-component system because both solid and liquid phases contains only the compound AB. Congruent melting point represents a definite temperature just like the melting points of pure components.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 化学稳定性是指化学系统的热力学稳定性，特别会用在化合物或聚合物上。 系统处于最低能级，或与其环境化学平衡时，此时的系统即有热力学稳定性。此稳定性可以是动态平衡，个别的原子或分子会进行化学变化，但其特殊形式的总数守恒。只要系统没有改变，此化学系统的热力学平衡可以一直持续。化学系统的改变包括有相的变化，也包括化学反应。 比较状态A和状态B，若从状态A变到状态B的吉布斯自由能为正，表示状态A比较具有热力学稳定性。
In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. Colloquially, it may instead refer to kinetic persistence, the shelf-life of a metastable substance or system; that is, the timescale over which it begins to degrade. Thermodynamic stability occurs when a system is in its lowest energy state, or in chemical equilibrium with its environment. This may be a dynamic equilibrium in which individual atoms or molecules change form, but their overall number in a particular form is conserved. This type of chemical thermodynamic equilibrium will persist indefinitely unless the system is changed. Chemical systems might undergo changes in the phase of matter or a set of chemical reactions. State A is said to be more thermodynamically stable than state B if the Gibbs free energy of the change from A to B is positive.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 离子注入是一种低温工艺，通过该工艺，可将特定离子在电场里加速，然后嵌入到另一固体靶材之中。如果注入离子在靶材内停留不逸出，就会改变靶材的元素成分。使用这个技术可以改变固体材料的物理、化学或电学性质，现在已经广泛应用于半导体器件制造和某些材料科学研究。离子注入带有能量的碰撞级联可能损伤甚至破坏靶材的晶体结构，当离子能量足够高（数十兆电子伏特）时，还可能导致核嬗变。
Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the target's physical, chemical, or electrical properties. Ion implantation is used in semiconductor device fabrication and in metal finishing, as well as in materials science research. The ions can alter the elemental composition of the target (if the ions differ in composition from the target) if they stop and remain in the target. Ion implantation also causes chemical and physical changes when the ions impinge on the target at high energy. The crystal structure of the target can be damaged or even destroyed by the energetic collision cascades, and ions of sufficiently high energy (tens of MeV) can cause nuclear transmutation.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 无穷小应变理论（infinitesimal strain theory）也称为无限小应变理论，是连续介质力学中描述固体形变的数学分析法，适用在其形变量远小于物体尺寸（无穷小量）的情形，因此若是均质材料，可以假设材料每一点的结构性质（密度及刚度）都相等，不会随变形而不同。 在此假设下，连续介质力学的方程可以简化。此作法也称为是小形变理论、小位移理论或小位移梯度理论。无穷小应变理论和有限应变理论的假设恰好相反，后者假设形变量没有远小于物体尺寸。 无穷小应变理论常用在土木工程及机械工程中，其中会进行结构的应力分析，而材料是用强度较高的混凝土及钢制成，而结构设计的目标也是在一般结构荷重下，希望其形变量可以降到最小。不过若分析的结构物是较细较薄，较容易变形的元件（例如杆、平板及薄壳），用无限小应变理论来分析就不可靠了。
In continuum mechanics, the infinitesimal strain theory is a mathematical approach to the description of the deformation of a solid body in which the displacements of the material particles are assumed to be much smaller (indeed, infinitesimally smaller) than any relevant dimension of the body; so that its geometry and the constitutive properties of the material (such as density and stiffness) at each point of space can be assumed to be unchanged by the deformation. With this assumption, the equations of continuum mechanics are considerably simplified. This approach may also be called small deformation theory, small displacement theory, or small displacement-gradient theory. It is contrasted with the finite strain theory where the opposite assumption is made. The infinitesimal strain theory has wide applications in engineering. Stress analysis, for example, tries to predict the behavior of structures built from relatively stiff elastic materials, such as concrete and steel. Such analysis can be used to minimize a structure design's deformation under typical loads.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
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