any solid object composed of randomly oriented crystalline regions, called crystallites (crystallite), especially as distinguished from a single crystal (q.v.). Polycrystalline materials result when a substance solidifies rapidly; crystallization commences at many sites (see nucleation), and the structurally ordered regions growing from each site intersect each other. The random arrangement of the boundaries between individual crystallites in a polycrystal causes them to scatter a beam of light instead of reflecting or refracting it uniformly, so that even colourless polycrystals are opaque. Other mechanical, electrical, or magnetic properties of single crystals are similarly altered by the absence of long-range order in polycrystals.

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Universalium. 2010.

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  • polycrystal — noun see polycrystalline …   New Collegiate Dictionary

  • Polycrystal — A photo of electrical steel (coating removed) showing polycrystalline structure Polycrystalline materials are solids that are composed of many crystallites of varying size and orientation. The variation in direction can be random (called random… …   Wikipedia

  • polycrystal — noun Any polycrystalline substance …   Wiktionary

  • polycrystal — Смотри Поликристалл …   Энциклопедический словарь по металлургии

  • polycrystal — poly·crystal …   English syllables

  • polycrystal — |pälē, lə̇+ noun Etymology: poly + crystal : a polycrystalline body or object …   Useful english dictionary

  • polycrystal silicon — polikristalinis silicis statusas T sritis radioelektronika atitikmenys: angl. polycrystal silicon; polysilicon vok. polykristallines Silizium, n; Polykristallsilizium, n; Polysilizium, n rus. поликремний, m; поликристаллический кремний, m pranc.… …   Radioelektronikos terminų žodynas

  • polycrystal isolation — izoliavimas polikristaliniu siliciu statusas T sritis radioelektronika atitikmenys: angl. polycrystal isolation vok. Polysilizium Isolation, f rus. изоляция поликристаллическим кремнием, f pranc. isolation par silicium polycri stallin, f …   Radioelektronikos terminų žodynas

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