Results for refractory
On this page:
 
Dictionary:

refractory

  (rĭ-frăk'tə-rē) pronunciation
adj.
  1. Obstinately resistant to authority or control. See synonyms at unruly.
  2. Difficult to melt or work; resistant to heat: a refractory material such as silica.
  3. Resistant to treatment: a refractory case of acne.
n., pl. -ries.
  1. One that is refractory.
  2. Material that has a high melting point.

[Alteration (influenced by adjectives in –ORY) of obsolete refractary, from Latin refrāctārius, from refrāctus, past participle of refringere, to break up. See refract.]

refractorily re·frac'to·ri·ly adv.
refractoriness re·frac'to·ri·ness n.
 
 

One of a number of ceramic materials for use in high-temperature structures or equipment. The term high temperatures is somewhat indefinite but usually means above about 1830°F (1000°C), or temperatures at which, because of melting or oxidation, the common metals cannot be used. In some special high-temperature applications, the so-called refractory metals such as tungsten, molybdenum, and tantalum are used. See also Ceramics.

The greatest use of refractories is in the steel industry, where they are used for construction of linings of equipment such as blast furnaces, hot stoves, and open-hearth furnaces. Other important uses of refractories are for cement kilns, glass tanks, nonferrous metallurgical furnaces, ceramic kilns, steam boilers, and paper plants. Special types of refractories are used in rockets, jets, and nuclear power plants. Many refractory materials, such as aluminum oxide and silicon carbide, are also very hard and are used as abrasives; some applications, for example, aircraft brake linings, make use of both characteristics.

Refractory materials are commonly grouped into (1) those containing mainly aluminosilicates; (2) those made predominantly of silica; (3) those made of magnesite, dolomite, or chrome ore, termed basic refractories (because of their chemical behavior); and (4) a miscellaneous category usually referred to as special refractories.


 
Antonyms: refractory

adj

Definition: obstinate
Antonyms: manageable, obedient


 
Dental Dictionary: refractory
(rē-frak′tər-ē)
adj

Pertaining to the ability to withstand the high temperatures used in certain dental laboratory procedures. See also cast, refractory.

 

Material that is not deformed or damaged by high temperatures, used to make crucibles, incinerators, insulation, and furnaces, particularly metallurgical furnaces. Refractories are produced in several forms: molded bricks of various shapes, bulk granular materials, plastic mixtures consisting of moistened aggregates that are rammed into place, castables composed of dry aggregates and a binder that can be mixed with water and poured like concrete, and mortars and cements for laying brickwork.

For more information on refractory, visit Britannica.com.

 
Architecture: refractory

A material, usually nonmetallic, used to withstand high temperatures.


 

Applied to a medical condition that does not respond to treatment.

 

Not readily yielding to treatment.

  • r. period — the period of depolarization and repolarization of the cell membrane after excitation; during the first portion (absolute refractory period), the nerve or muscle fiber cannot respond to a second stimulus, whereas during the relative refractory period, it can respond only to a strong stimulus.
  • myocardial r. state — the myocardium is refractory to stimulation during the action potential period, excitability returning in the repolarization phase; initially there is a period of supernormality.
 
Word Tutor: refractory
pronunciation

IN BRIEF: Resisting control or authority. Also: Capable of enduring high temperatures.

pronunciation The refractory child changed her behavior when she suffered the consequences of her actions.

 
Wikipedia: refractory

The term refractory refers to the quality of a material to retain its strength at high temperatures. Refractory materials are used to make crucibles and linings for furnaces, kilns and incinerators. There is no clearly established boundary between refractory and non-refractory materials, though a practical requirement often cited is the ability of the material to withstand temperatures above 1100 °C without softening.

Refractory materials

Main article: Refractory metals

Refractory materials must be strong at high temperatures, resistant to thermal shock, chemically inert, and have low thermal conductivities and coefficients of expansion.

The oxides of magnesium (magnesia) and calcium (lime) are the most important refractory materials, though fireclay is widely used as well. Zirconia is used when the material must withstand extremely high temperatures. Silicon carbide is another refractory material. It is very strong at high temperatures, but will burn in the presence of oxygen, if the protective silica coating comes off. Refractories must be chosen according to the conditions they will face. For example, carbon cannot be used when it will be in contact with oxygen, as it will burn.

Types of refractories

Acidic refractories cannot be used in a basic environment and basic refractories cannot be used in acidic environment because they will be corroded. Zircon, fireclay and silica are acidic, dolomite and magnesite are basic and alumina, chromite, silicon carbide, carbon and mullite are neutral. Refractory metals are also frequently used.

Refractory Anchorage

Anti-abrasion refractory attached to pipes, chambers, etc, will require anchorage systems such as wire formed anchors or hexmetal to support the refractory linings.


 
Translations: Translations for: Refractory

Dansk (Danish)
adj. - stædig, uregerlig, upåvirkelig, uimodtagelig
n. - modstandsdygtigt materiale, ildfast materiale

Nederlands (Dutch)
weerspannig, immuun, niet makkelijk te genezen, bestand tegen hoge temperaturen, (mv) materiaal bestand tegen hitte/corrosie

Français (French)
adj. - réfractaire (tous contextes)
n. - réfractaire

Deutsch (German)
adj. - störrisch, hartnäckig, hitzebeständig
n. - hitzebeständiges Metall

Ελληνική (Greek)
adj. - ανυπότακτος, ατίθασος, ανυπάκουος, δύσκολος, επίμονος
n. - αλεξίπυρη ύλη

Italiano (Italian)
ricalcitrante, refrattario

Português (Portuguese)
adj. - refratário
n. - refratário (m)

Русский (Russian)
огнеупорный, тугоплавкий, упрямый

Español (Spanish)
adj. - refractario, obstinado
n. - persona obstinada, objeto refractario

Svenska (Swedish)
adj. - motspänstig, svårarbetad
n. - kem o fys stabilt material

中文(简体) (Chinese (Simplified))
执拗的, 难治的, 有抵抗力的, 耐火的, 耐火物质, 倔强的人, 耐火砖

中文(繁體) (Chinese (Traditional))
adj. - 執拗的, 難治的, 有抵抗力的, 耐火的
n. - 耐火物質, 倔強的人, 耐火磚

한국어 (Korean)
adj. - 난치의, 용해하기 어려운, 감당할 수 없는
n. - 내화 물질

日本語 (Japanese)
adj. - 手に負えない, 難治の, 不応の, 溶解しにくい, 耐火性の, 強情な
n. - 頑固な人, 耐火材

العربيه (Arabic)
‏(صفه) عنيد, مقاوم للعلاج, ذو مناعه (الاسم) مادة مقاومه للحرارة‏

עברית (Hebrew)
adj. - ‮עקשן, מרדני, שקשה להתיכה (מתכת), קשה-ריפוי, מחוסן‬
n. - ‮עקשן, מרדני, שקשה להתיכה (מתכת), קשה-ריפוי, מחוסן, חומר בעל כושר התנגדות חזק לחום ולאיכול‬


 
 

Join the WikiAnswers Q&A community. Post a question or answer questions about "refractory" at WikiAnswers.

 

Copyrights:

Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2007. Published by Houghton Mifflin Company. All rights reserved.  Read more
Sci-Tech Encyclopedia. McGraw-Hill Encyclopedia of Science and Technology. Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved.  Read more
Thesaurus. Roget's II: The New Thesaurus, Third Edition by the Editors of the American Heritage® Dictionary Copyright © 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.  Read more
Answers Corporation Antonyms. © 1999-2008 by Answers Corporation. All rights reserved.  Read more
Dental Dictionary. Mosby's Dental Dictionary. Copyright © 2004 by Elsevier, Inc. All rights reserved.  Read more
Britannica Concise Encyclopedia. Britannica Concise Encyclopedia. © 2006 Encyclopædia Britannica, Inc. All rights reserved.  Read more
Architecture. McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc. All rights reserved.  Read more
Sports Science and Medicine. The Oxford Dictionary of Sports Science & Medicine. Copyright © Michael Kent 1998, 2006, 2007. All rights reserved.  Read more
Veterinary Dictionary. Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved.  Read more
Word Tutor. Copyright © 2004-present by eSpindle Learning, a 501(c) nonprofit organization. All rights reserved.
eSpindle provides personalized spelling and vocabulary tutoring online; free trial Read more
Wikipedia. This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Refractory" Read more
Translations. Copyright © 2007, WizCom Technologies Ltd. All rights reserved.  Read more

Search for answers directly from your browser with the FREE Answers.com Toolbar!  
Click here to download now. 

Get Answers your way! Check out all our free tools and products.

On this page:   E-mail   print Print  Link  

 

Keep Reading

Mentioned In: