Материал: 1493
pipes, machines and automotive industry parts, such as |
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cylinder heads (declining usage), cylinder blocks and gearbox |
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cases (declining usage). It is resistant to destruction and |
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weakening by oxidation (rust) |
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It is the cast iron that displays white fractured surface due |
Чугун белый – |
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to the presence of cementite. With a lower silicon content |
чугун, в |
котором |
(graphitizing agent) and faster cooling rate, the carbon in |
весь |
углерод |
white cast iron precipitates out of the melt as the metastable |
находится в виде |
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phase cementite, Fe3C, rather than graphite. The cementite |
карбида |
железа |
which precipitates from the melt forms as relatively large |
или цементита |
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particles, usually in a eutectic mixture, where the other phase |
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is austenite (which on cooling might transform to martensite). |
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These eutectic carbides are much too large to provide |
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precipitation hardening (as in some steels, where cementite |
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precipitates might inhibit plastic deformation by impeding the |
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movement of dislocations through the ferrite matrix). Rather, |
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they increase the bulk hardness of the cast iron simply by |
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virtue of their own very high hardness and their substantial |
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volume fraction, such that the bulk hardness can be |
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approximated by a rule of mixtures. In any case, they offer |
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hardness at the expense of toughness. Since carbide makes up |
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a large fraction of the material, white cast iron could |
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reasonably be classified as a cermet. White iron is too brittle |
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for use in many structural components, but with good |
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hardness and abrasion resistance and relatively low cost, it |
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finds use in such applications as the wear surfaces (impeller |
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and volute) of slurry pumps, shell liners and lifter bars in ball |
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mills and autogenous grinding mills, balls and rings in coal |
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pulverisers, and the teeth of a backhoe's digging bucket |
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(although cast medium-carbon martensitic steel is more |
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common for this application). |
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It is difficult to cool thick castings fast enough to solidify |
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the melt as white cast iron all the way through. However, |
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rapid cooling can be used to solidify a shell of white cast iron, |
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after which the remainder cools more slowly to form a core of |
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grey cast iron. The resulting casting, called a chilled casting, |
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has the benefits of a hard surface and a somewhat tougher |
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interior |
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Malleable iron starts as a white iron casting that is then |
Чугун ковкий – |
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heat treated at about 900 °C. Graphite separates out much |
ковкий |
чугун |
more slowly in this case, so that surface tension has time to |
получают |
путем |
form it into spheroidal particles rather than flakes. Due to |
отжига |
отливок |
their lower aspect ratio, spheroids are relatively short and far |
белого чугуна |
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from one another, and have a lower cross section vis-a-vis a |
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propagating crack or phonon. They also have blunt |
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boundaries, as opposed to flakes, which alleviates the stress |
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concentration problems faced by grey cast iron. In general, |
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the properties of malleable cast iron are more like mild steel. |
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There is a limit to how large a part can be cast in malleable |
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iron, since it is made from white cast iron |
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Grey cast iron is characterised by its graphitic |
Чугун серый – |
microstructure, which causes fractures of the material to have |
углерод в сером |
a grey appearance. It is the most commonly used cast iron and |
чугуне |
the most widely used cast material based on weight. Most cast |
присутствует в |
irons have a chemical composition of 2.5–4.0% carbon, 1–3% |
виде |
silicon, and the remainder is iron. Grey cast iron has less |
пластинчатого |
tensile strength and shock resistance than steel, but its |
или волокнистого |
compressive strength is comparable to low and medium |
графита |
carbon steel |
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Задание 3. Используя информацию схем, представленных ниже, постройте учебный текст, описывающий понятие чугун, на английском языке.
Схема 21. Чугун
Чугун
Ковкий чугун
Серый чугун
Белый чугун
Крупнозернистый
Мелкозернистый
Твердый чугун
Чугун в болванках
Чугуновоз
Cast iron, iron
annealed (malleable) cast iron, wrought iron
grey cast iron
white cast iron
coarse-grain cast iron, open-grained cast iron, very-open-grained pig iron
close-grain cast iron, fine-grained iron
cold pig iron
pig iron, sow
hot-metal transfercar
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Задание 4. Переведите толкование понятия.
Definition |
Translation |
A metal is a solid material (an element, compound, or alloy) that is typically hard, shiny, and feature good electrical and thermal conductivity. Metals are generally malleable – that is, they can be hammered or pressed permanently out of shape without breaking or cracking – as well as fusible (able to be fused or melted) and ductile (able to be drawn out into a thin wire). Currently, 91 out of the 118 total elements on the periodic table are classified as metals
Задание 5. Переведите текст, организуйте информацию, данную в нем, в опорную схему. Перескажите текст, используя полученную схему.
Metal
Metal is used as structural framework for larger buildings such as skyscrapers, or as an external surface covering. There are many types of metals used for building. Metal figures quite prominently in prefabricated structures such as the Quonset hut, and can be seen used in most cosmopolitan cities. It requires a great deal of human labor to produce metal, especially in the large amounts needed for the building industries. Corrosion is metal's prime enemy when it comes to longevity.
Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural building materials. It is strong, flexible, and if refined well and/or treated lasts a long time.
The lower density and better corrosion resistance of aluminium alloys and tin sometimes overcome their greater cost.
Copper is a valued building material because of its advantageous properties (see: Copper in architecture). These include corrosion resistance, durability, low thermal movement, light weight, radio frequency shielding, lightning protection, sustainability, recyclability, and a wide range of finishes. Copper is incorporated into roofing, flashing, gutters, downspouts, domes, spires, vaults, wall cladding, building expansion joints, and indoor design elements.
Other metals used include chrome, gold, silver, and titanium. Titanium can be used for structural purposes, but it is much more expensive than steel. Chrome, gold, and silver are used as decoration, because these materials are expensive and lack structural qualities such as tensile strength or hardness.
Задание 6. Прочитайте и переведите данные ниже предложения. На основе сведений, полученных о понятии, и схем, представленных ниже, составьте учебный текст о понятии металл.
Concrete has roughly the same coefficient of thermal expansion as iron.
All these works are the result of an attempt to put an end to imitations of past styles; in its place is offered a florid type of architecture, which exploits craft skills,
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using coloured materials (faience cabochons, stoneware, terracotta panels, stained glass), exotic veneers, moulded stonework, grilles, balconies, and tapered brackets in wrought iron; and burgeoning with asymmetrical door – and window – frames, bow and horseshoe windows, etc.
Metals were scarcely available, save for iron, which was used primarily for weapons.
There was also debate about the use of iron and steel: should these new materials be visible, as in the new bridges and railway stations, or hidden, as in the Natural History Museum, London, where the metal frame is covered by coloured brick and stonework?
Metals: Aluminium, principally in the form of various alloys, is highly valued for its durability and especially for its light weight, while brass is frequently used for decorative purposes in facing.
Steel finds its use in corrugated sheets for roofing, for girders, frames, etc.
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Схема 22. Металл |
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Металл |
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Metal |
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Черный/цветной металл
Сталь
Ковкая мягкая сталь
Конструкционная сталь
Серебро
Хром
Титан
Медь
Железо
Листовое железо
Золото
Тяжелые сплавы
ferrous/nonferrous metal
steel
wrought iron
structural steel
silver
chrome
titanium
copper
iron
sheet iron
gold
heavy (high-density) alloy, heavy metal
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Модуль 11. СТРОИТЕЛЬНЫЕ МАТЕРИАЛЫ И ИЗДЕЛИЯ ИЗ ДРЕВЕСИНЫ
Задание 1. На основе информации, данной в переводе, и текста, представленного после таблицы, дайте развернутое толкование понятия. Используйте следующие выражения:
измельчение и расщепление древесины – timber grinding and splitting волокнистая масса – fiber, pulp
отливка плит – slab casting
с последующим прессованием и сушкой – with following moulding and drying для внутренней отделки – for interior trim
перфорированные и изоляционные плиты – pegboards and lith boards особо высокие акустические свойства – particular acoustic properties
Definition Translation
Древесно-волокнистые плиты (ДВП) – тепло-, звукоизоляционный и конструктивный древесный материал; изготавливается путём измельчения и расщепления древесины (или другого растительного сырья) в волокнистую массу, отливки из неё плит с последующим прессованием и сушкой. Различают по твёрдости: сверхтвёрдые, твёрдые и полутвёрдые. В зависимости от отделки (окрашивание эмалями, облицовка бумажными пластиками, полимерными плёнками и т.п.) и твёрдости плиты находят применение в строительстве. Твёрдые и сверхтвёрдые плиты используются для внутренней отделки жилых и общественных зданий, полутвердые и твердые находят применение в отделке потолков и панелей, сверхтвердые плиты и плиты, пропитанные смолами, применяют для полов. В ряде случаев применяются двухслойные и многослойные плиты, склеенные из твёрдых перфорированных (лицевой слой) и изоляционных (внутренний слой) плит. Изоляционноотделочные плиты служат для отделки помещений, требующих особо высоких акустических свойств. Изоляционные плиты используются для тепло- и звукоизоляции стен, перегородок, полов и потолков в жилых помещениях, а также для утепления кровельных покрытий
Fiberboard
Fiberboard is a type of engineered wood product that is made out of wood fibers. Types of fiberboard (in order of increasing density) include particle board, mediumdensity fiberboard, and hardboard. Fiberboard is sometimes used as a synonym for particle board, but particle board usually refers to low-density fiberboard. Plywood is
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