investment casting

investment casting
a casting process in which an expendable pattern is surrounded by an investment compound and then baked so that the investment is hardened to form a mold and the pattern material may be melted and run off. Also called precision casting. Cf. lost-wax process.

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Precision casting for forming metal shapes with minutely precise details.

Casting bronze or precious metals typically involves several steps, including forming a mold around the sculptured form; detaching the mold (in two or more sections); coating its inside with wax; forming a second mold, of heat-resisting clay, around the wax shell, and filling the interior with a clay core; baking the assembly (hardening the clay and melting the wax, which escapes through openings in the outer mold); pouring molten bronze into the space vacated by the wax; and breaking the mold to expose the cast form. In modern foundries, plastics, or occasionally frozen mercury, are used instead of wax. See also lost-wax casting, die casting.

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      precision-casting technique for forming metal shapes. A typical process for bronze castings involves six steps:

      1. A gelatin mold is formed around the solid sculptured form.

      2. The mold is removed (in two or more sections) from the sculptured form, and the inside of the mold is filled with wax or coated with a layer of wax of the same thickness as that desired for the final casting.

      3. The outer gelatin mold is then removed, and a second mold, of heat-resisting clay, is formed around the wax shell, the interior of which is filled with a clay core.

      4. The mass is baked, hardening the clay and melting the wax, which runs off through openings in the outer mold.

      5. The hardened mold is packed in sand, and molten bronze is poured through the openings to fill the space vacated by the lost wax.

      6. The mold is broken, and the bronze form remains.

      In modern foundries, plastics (plastic), or occasionally frozen mercury, are used in place of the wax. Coated with a refractory cement instead of clay, the mold is packed in a porous cement, dried, and heated. The plastic melts, leaving cavities to be filled with molten metal. For all except the smallest forms, the molds are usually made in sections. The process is used for manufacturing jewelry, dentures, sculpture, and many small industrial parts that require minutely precise details. See also lost-wax process.

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Universalium. 2010.

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Look at other dictionaries:

  • Investment casting — Investment casting. См. Точное литье по выплавляемым моделям. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург, 2003 г.) …   Словарь металлургических терминов

  • Investment casting — For investment casting in art, see lost wax casting. Investment casting, also called lost wax casting, is one of the oldest known metal forming techniques. From 5,000 years ago, when beeswax formed the pattern, to today’s high technology waxes,… …   Wikipedia

  • investment casting — /ɪnˈvɛstmənt kastɪŋ/ (say in vestmuhnt kahsting) noun a casting process used in metallurgy in which a pattern coated by a compound or plaster is baked with the result that the compound hardens to form an investment and the pattern then melts and… …  

  • investment casting — noun Etymology: investment (I) : casting by the cire perdue process …   Useful english dictionary

  • investment casting — (voz inglesa) ► METALURGIA Método de moldeo de precisión basado en el empleo de matrices de cera. Se llama también fundición a la cera perdida …   Enciclopedia Universal

  • Casting (metalworking) — Casting iron in a sand mold In metalworking, casting involves pouring liquid metal into a mold, which contains a hollow cavity of the desired shape, and then allowing it to cool and solidify. The solidified part is also known as a casting, which… …   Wikipedia

  • casting — /kas ting, kah sting/, n. 1. the act or process of a person or thing that casts. 2. something cast; any article that has been cast in a mold. 3. the act or process of choosing actors to play the various roles in a theatrical production, motion… …   Universalium

  • investment — /in vest meuhnt/, n. 1. the investing of money or capital in order to gain profitable returns, as interest, income, or appreciation in value. 2. a particular instance or mode of investing. 3. a thing invested in, as a business, a quantity of… …   Universalium

  • investment compound — /ɪnˈvɛstmənt kɒmpaʊnd/ (say in vestmuhnt kompownd) noun a compound used in investment casting …  

  • Casting defect — A casting defect is an irregularity in the metal casting process that is undesired. Some defects can be tolerated while others can be repaired otherwise they must be eliminated. They are broken down into five main categories: gas porosity,… …   Wikipedia

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