HEXAGONAL BORON NITRIDE POWDER
Molecular formula: BN
Molecular weight: 24.82
BN: = 99/98/97%
Boron free: less than 0.4/0.5/0.8%
characteristic：
Boron nitride is composed of boron and nitrogen atoms of the crystal, the crystal structure is divided into: hexagonal boron nitride (HBN), densely arranged hexagonal boron nitride (WBN) and cubic boron nitride. The crystal structure of hexagonal boron nitride has similar lamellar graphite structure, presenting loose, smooth, easy to absorb tide, light quality traits of white powder, so it is also called "white graphite. Theoretical density 2.27g/ cm3, the proportion: 2.43, type of hardness for 2. Hexagonal boron nitride is has the good electric insulation, thermal conductivity, chemical stability, no obvious melting point, in nitrogen 0.1MPa 3000 DEG C, in neutral reduction atmosphere and resistance 2000 DEG C, in argon, nitrogen and temperature can reach 2800 0C, stability is poor in oxygen atmosphere, below 1000 DEG C temperature. The expansion coefficient of the six party is equivalent to that of quartz, but the thermal conductivity is ten times of that of quartz. Also has good lubrication at high temperature, is an excellent high temperature solid lubricant, there is a strong neutron absorption capacity, stable chemical properties, almost all of the molten metal is chemically inert.
Hexagonal boron nitride insoluble in cold water, the water boiling hydrolysis is very slow and produces a small amount of boric acid and ammonia, and weak acid and alkali at room temperature are not react, slightly soluble in hot acid, molten sodium hydroxide and potassium hydroxide to decompose. Against all kinds of inorganic acid, alkali, salt solution and organic solvents have a considerable capacity to resist corrosion.
Hexagonal boron nitride is one of the ceramic materials in the thermal conductivity of materials, the largest, the thermal conductivity is ten times of quartz, high coefficient of heat conductivity and hot pressing product for 33W/M.K and iron as; expansion coefficient is equal to that of quartz is ceramic minimum. In the c-axis direction of thermal expansion coefficient for 41x10^6/C in d axis direction for -2.3x10^6/C, so thermal shock performance very good. Boron nitride is ceramic in the best thermal insulation materials, breakdown voltage 3KV/MM, low dielectric loss 108HZ for 2.5x10^-4, dielectric constant of 4, penetrable by microwave and infrared.

Boron nitride parameter:
1, high heat resistance: 3000 degrees sublimation, the strength of 1800 degrees Celsius for 2 times the room temperature, 1500 degrees cold to room temperature for dozens of times does not break, in the inert gas 2800.
2, high thermal conductivity, hot pressing product for 33W/M.K and iron as, in more than 530 C ceramic materials in the thermal conductivity of materials, the largest.
3, low thermal expansion coefficient: 2 x 10-6 expansion coefficient second only to quartz glass, ceramics are the smallest, with its high thermal conductivity, so the thermal shock resistance is very good.
4, excellent electrical properties: high temperature insulation good, 25 DEG C to 1014 ohm cm, 2000 DEG C can also be reached 103 Omega cm, ceramic in the best thermal insulation materials, breakdown voltage 3KV/MV, low dielectric loss 108HZ for 2.5 x 10-4, dielectric constant for 4, penetrable by microwave and infrared.
5, good corrosion resistance, and general metals (iron, copper, aluminum, lead, etc.), rare earth metals, precious metals, semiconductor materials (germanium, silicon, potassium arsenic), glass, molten salt (crystal stone, fluoride, slag), inorganic acid, alkaline reaction.
6, a low coefficient of friction: u is 0.16, high temperature does not increase, than MoS2 and graphite high temperature, oxidizing atmosphere available to 900 DEG C, vacuum can
Use 2000 degrees C.
7, high purity boron containing high: the impurity content is less than 10PPM, while the boron containing more than 43.6%.
8, mechanical processing: the Mohs hardness 2, so can be used in general machining method into high precision parts.
Application range:
To boron nitride is a non-toxic, high temperature resistance, corrosion resistance, high thermal conductivity, high insulation materials, excellent lubricating properties.
* is an electrical insulator and conductor of heat, under the condition of high temperature special electrolysis, resistance material, high voltage and high frequency electric and plasma arc insulator.
Grease may as semiconductor solid-state doping materials, antioxidant or water resistant.
* high temperature lubricants and model of release agent, boron nitride powder can also be used as the anti adhesive of glass beads, glass and metal forming release agent.
It is made of boron nitride superhard material, can be made of high speed cutting tools, geological exploration, oil drilling bit.
* atomic reactor structural materials, aircraft and rocket engine spray to prevent neutron radiation of packaging materials and aerospace in the heat shield material.
It is non-toxic and harmless and lubricity, can be used as a cosmetic filler.
You in the catalyst in the presence of the high temperature and high pressure processing can be transformed as hard as the diamond cubic boron nitride.
To do all kinds of capacitor film evaporator of aluminum, aluminum, aluminum tube display etc..
First transistor heat sealing additive desiccant and plastic resin and other polymer.
* various laser antifalsification aluminized, trademark bronzing materials, cigarette, beer label, packing box, cigarette packaging box aluminum plating and so on.
Storage precautions
1, this product is non-toxic, harmless, non flammable, explosive chemicals can according to the general transportation.
2, put in a cool, dry place, rain, moisture, avoid eating.