Boron Nitride cbn is an advanced ceramic known for its superior properties. BN chemistry has Bor-Stickstoff bonds that give rise to different structures. Of the structures of BN one such prominent structure of interest is Cubic Boron Nitride cbn. Let us try to understand c-bn and its relative aspects.
Table of Contents
- Structure of Hexagonal Boron Nitride
- Properties of Hexagonal Boron Nitride
- Anwendungen von hexagonalem Bornitrid
- What is cubic Boron Nitride?
- Structure of Cubic Boron Nitride
- Eigenschaften von kubischem Bornitrid
- Kubisches Bornitrid vs. Diamant
- Verwendung von kubischem Bornitrid
- Super abrasive wheels – or diamond c-BN wheel
Bornitrid: An Overview
Bornitrid is indicated by chemical formula “BN.” As earlier mentioned, Bornitrid exist in different forms. Generally, it is the location of Boron and Nitrogen in lattice that creates various Boron Nitride structures. Some of them are quiet famous such as amorphous, hexagonal, cubic and Wurtzite.
When it comes to functionality, Boron Nitride ceramic is highly machinable. Once machined they does not really require any heat sintering or treatment for stabilization. In addition, Bornitrid has higher heat capacity and is also a good electrical insulator.
For now, let’s try to understand derivatives of BN, Hexagonales Bornitrid (h-BN) and another Cubic Boron Nitride (c-BN)
Hexagonales Bornitrid (h-BN)
Structure of Hexagonal Boron Nitride
Hexagonales Bornitrid is a constituent in many industrial products such as cosmetics. HBN has a structure controlled by covalent bonds. However, the layers in HBN obey wander Waals forces. The plate like geometry of HBN is the reason why it is ideal for lubrication.
Hexagonales Bornitrid has elements of Boron and Nitrogen fixed to its lattice. The arrangement has three nitrogen atoms attached to a Boron Atom. The similarity in the honeycomb structure is the reason for its analogy with carbon. In addition to, properties of mechanical, chemical strength and electrical insulation are due to the planar triangular bonds
Properties of Hexagonal Boron Nitride
Hexagonales Bornitrid is popularly manufactured through Boric Oxide nitridation at elevated temperatures. Since its stability is closer to graphene, Hexagonales Bornitrid is often acclaimed as the most advanced technical ceramic. Some superior properties of Hexagonales Bornitrid sind seine Wärmeleitfähigkeit und sein niedriger Reibungskoeffizient.
Anwendungen von hexagonalem Bornitrid
- HBN is used on nanoelectronics devices as a substitute to graphene substrate
- Hexagonales Bornitrid in its thin form is used as coatings that resists corrosion
- HBN is often used in the manufacture of sensor materials. It is also used in electron tunneling due to its low value of dielectric constant.
Kubisches Bornitrid
What is cubic Boron Nitride?
c-BN ist ein Derivat von Hexagonales Bornitrid (h-BN) produced under high temperature and pressure.
Die größte Spezialität von c-BN ist, dass es den Platz des zweithärtesten Materials der Welt einnimmt. Die mechanische Festigkeit von Kubisches Bornitrid ist beliebt und steht dem Diamanten in nichts nach. Es ist eines der beliebtesten Polymorphe von Bor Nitrid.
Structure of Kubisches Bornitrid
The basic structure of Kubisches Bornitrid is crystalline. It has density around 3.5 g/cm3 and appears in pale yellow or transparent complexion. C-BN follows alternate arrangement of Boron and Nitrogen atoms. Here, the Bor-Stickstoff atoms follow covalent bonding which is the basic reason of its hardness and stability.
Cubic Boron Nitride Formula is given as c-BN. There are two popular types of c-Bn available today in the market. One is dense kubisches Bornitrid and the other polycrystalline cubic Boron Nitride.
Cubic Boron Nitride Properties
C-BN is a brilliant semiconductor whose bandgaps are susceptible to changes in applied pressure. These changes in bandgap helps them excel as electric insulators. Kubisches Bornitrid are generally inert and possesses low dielectric constant value. Their thermal conductivity is around 1300 KW/MK.
When it comes to reactivity, c-BN remains non-respondent even to ferrous materials. The optical range dealt by kubisches Bornitrid varies from Ultra violet to the visible spectrum.
Kubisches Bornitrid vs. Diamant
Obwohl nicht härter als Diamant, kubisches Bornitrid hat im Vergleich zu Diamanten seinen besonderen Stellenwert. Cubic boron Nitride hardness is 4500 Kg/mm2 whereas diamond has hardness around 600 Kg/mm2.The value of modulus both young’s and bulk are also in similar range of 800 – 1000 and 370 – 450.
Furthermore, when it comes to structure, like diamond, c-BN has its two base atoms that are different. The similarity of both diamond and c-BN is generally attributed to the lookalike structure they possess.
Verwendung von kubischem Bornitrid
CBN-Schneidwerkzeugmaterial
Kubisches Bornitrid exhibits both young’s and Bulk modulus greater than Boron Carbide and Silicon Carbide. This very reason strongly contributes to the hardness of cubic Boron Nitride. The hardness makes them suitable as abrasives and help them function as CBN-Schneidwerkzeugmaterial. Generally Dense c-Bn is used for cutting application and porous type for grinding requirements.
The inert nature of Cubic Boron Nitride also helps them function as cutting and machining material. Unlike diamond it doesn’t react to iron. However, conventional c-Bn requires manipulation for utilising it in cutting application. This is generally done during the conversion of h-Bn to c-Bn while sintering.
cbn as electrical insulators
Apart from hardness Kubisches Bornitrid also excels in electrical insulators. This is attributed to their wide bandgap.
cbn in semiconductor applications
By coating aluminium and Group 8 metals, C-BN functionality of becoming a sink is popular in electronic industry. C-BN is used as heat sink in lasers, microelectronic devices and LEDs.
Kubisches Bornitrid also adds value during semiconductor synthesis to obtain p and N type by proper doping. The common materials used for doping are Silicon or Beryllium. These semiconductors work at high temperature and are used in UV sensors.
c-BN Schleifscheiben
Die Erfindung von c-BN Schleifscheiben merited precision manufacturing due to the increased efficiency. wheels made up of c-BN contributed to industries such as aerospace, machines, tool production and automobile. c-BN Schleifscheiben also offer high hardness and good performance on comparison with SiC and Alumina. They ensure structural integrity at higher temperature and undergo no degradation.
The wheels of c-BN can withstand high temperature and deals with the amount of heat generated during the process. The resistance to wear and tear is also economically beneficial while considering c-BN grinding wheels. c-BN grinding wheels offer excellent surface finish and keeps away the work piece wastage. It also ensures lesser cycle time as the tasks are done quickly and precisely.
Super abrasive wheels – or diamond c-BN wheel
The super abrasive wheels are the ones differ from conventional wheel of Sic and Alumina. They are made from combining c-Bn and diamond. The super abrasive wheel offers better thermal conductivity limiting the rise in temperature of the workpiece. The Diamant-C-Bn-Rad bieten außerdem hohe Genauigkeit und Präzisionsschnitte, die zu einer längeren Lebensdauer beitragen.
Abschluss
Kubisches Bornitrid ist in der modernen Wissenschaft und Materialherstellung gefragt. Sie sind im Vergleich zu Materialien wie Diamant konkurrenzfähig. Sie zeichnen sich durch Eigenschaften wie Härte, Festigkeit und elektrische Isolierung aus. Die große Bandlücke, die inerte Natur, die niedrige Dielektrizitätskonstante und optische Besonderheiten sind weitere Vorteile.