FACTOID # 20: Statistically, Delaware bears more cost of the US Military than any other state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Boron carbide
Boron carbide
IUPAC name Boron carbide
Other names Tetrabor
B4-C
B4C
Black Diamond
Identifiers
CAS number 12069-32-8
Properties
Molecular formula B4C
Molar mass 55.255 g/mol
Appearance Black powder.
Density 2.52 g/cm3, solid.
Melting point

2350 °C (2623.15 K) IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... For other uses, see Density (disambiguation). ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ...

Boiling point

>3500 °C (>3773.15 K) Italic text This article is about the boiling point of liquids. ...

Solubility in water Insoluble.
Structure
Crystal structure Rhombohedral
Hazards
MSDS External MSDS
Main hazards Harmful, irritant.
Related Compounds
Related compounds Boron nitride
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Boron carbide (chemical formula B4C) is an extremely hard ceramic material used in tank armor, bulletproof vests, and numerous industrial applications. With a hardness of 9.3 on the mohs scale, it is the fifth hardest material known behind boron nitride, diamond, ultrahard fullerite, and aggregated diamond nanorods. Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Enargite crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... In crystallography, the rhombohedral (or trigonal) crystal system is one of the 7 lattice point groups. ... This page meets Wikipedias criteria for speedy deletion. ... The examples and perspective in this article or section may not represent a worldwide view. ... Boron nitride is a binary chemical compound, consisting of equal proportions of boron and nitrogen, with formula BN. Structurally, it is isoelectronic to carbon and takes on similar physical forms: a hexagonal, graphite-like one, and a cubic, diamond-like one. ... In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals) and 25 degrees Celsius (298. ... Fixed Partial Denture, or Bridge The word ceramic is derived from the Greek word κεραμικός (keramikos). ... Armor or armour (see spelling differences) is protective clothing intended to defend its wearer from intentional harm in combat and military engagements, typically associated with soldiers. ... This article or section does not adequately cite its references or sources. ... Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer. ... Boron nitride is a binary chemical compound, consisting of equal proportions of boron and nitrogen, with formula BN. Structurally, it is isoelectronic to carbon and takes on similar physical forms: a hexagonal, graphite-like one, and a cubic, diamond-like one. ... This article is about the gemstone. ... Scratch caused by ultrahard fullerite on diamond Ultrahard fullerite (C60) is a form of carbon found to be harder than diamond, and which can be used to create even harder materials, such as aggregated diamond nanorods. ... Aggregated diamond nanorods, or ADNRs, are an allotrope of carbon believed to be the least compressible material known to humankind, as measured by its isothermal bulk modulus; aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), while a conventional diamond has a modulus of 442 GPa. ...


Discovered in the 19th century as a by-product of reactions involving metal borides, it was not until the 1930s that the material was studied scientifically. Boron carbide is now produced industrially by the carbo-thermal reduction of B2O3 (boron oxide) in an electric arc furnace. Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... The 1930s (years from 1930–1939) were described as an abrupt shift to more radical and conservative lifestyles, as countries were struggling to find a solution to the Great Depression, also known as the World Depression. ... Boron oxide is a colourless or white solid, also known as Diboron trioxide, formula B2O3. ... Steel mill with two arc furnaces An electric arc furnace is a system that heats charged material by means of an electric arc. ...


Its ability to absorb neutrons without forming long lived radionuclides makes the material attractive as an absorbent for neutron radiation arising in nuclear power plants. Nuclear applications of boron carbide include shielding, control rod and shut down pellets. Within control rods, boron carbide is often powdered, to increase its surface area. A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created radiation particle within the nucleus, or else to an atomic electron (see internal conversion) . The radionuclide, in this process, undergoes radioactive decay...


Applications

Armor plating is by definition to install armor, typically on a vehicle. ... It has been suggested that this article or section be merged into Ceramic plate. ... A tipped tool or insert generally refers to any cutting tool where the cutting edge consists of a seperate piece of material, either brazed or clamped on to a seperate body. ... A die is a tool used in the manufacturing industry to create a wide variety of products and components. ... An abrasive is a usually rough object that is used to smooth another through extensive rubbing. ... Grinding wheel A grinding wheel is an expendable wheel that carries an abrasive compound on its periphery. ... This article or section does not adequately cite its references or sources. ... A control rod is a rod made of a chemical element capable of absorbing many neutrons without decaying themselves. ... Core of a small nuclear reactor used for research. ...

References

  • Carbide, Nitride and Boride Materials Synthesis and Processing ISBN 0-412-54060-6

External links

  • National Pollutant Inventory - Boron and compounds
  • NIST Chemistry Database Entry for Boron Carbide

  Results from FactBites:
 
Surface modification of boron carbide to form pockets of solid lubricant - Patent 5075130 (4278 words)
Boron carbide, one of the hardest and most durable materials known to man, has a hardness of approximately 45% that of the hardness of a diamond.
The boron carbide hard material which is found in close association with the nitrogen-implanted and annealed portion of the surface boron nitride would act as a wear resistant material to protect the lubricious boron nitride from abrading away.
This chemical bonding of boron and nitrogen near the surface of the boron carbide sample was further evaluated and ascertained using x-ray photoelectron spectroscopy with conventional 3 keV (kilo electron volts) argon sputtering.
Boron Carbide (B4C) - Properties and Information about Boron Carbide (467 words)
Boron Carbide is one of the hardest materials known, ranking third behind diamond and cubic boron nitride.
Due to its high hardness, boron carbide powder is used as an abrasive in polishing and lapping applications, and also as a loose abrasive in cutting applications such as water jet cutting.
Boron carbide, in conjunction with other materials also finds use as ballistic armour (including body or personal armour) where the combination of high hardness, high elastic modulus, and low density give the material an exceptionally high specific stopping power to defeat high velocity projectiles.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m