Properties of boron nitride

There are two types of BN materials in boron nitride (BN) ceramics: hexagonal and cubic structures. The hexagonal boron nitride crystal structure has a similar graphite layered structure, presenting a loose, lubricating, easily hygroscopic, lightweight white powder, also known as "white graphite.". Theoretical density: 2.27g/cm3; The Mohs hardness is 2. Hexagonal boron nitride has excellent electrical insulation, thermal conductivity, and chemical stability; No obvious melting point, and sublimation at 3000 ℃ in 0. IMPa nitrogen, melting point at 3000 ℃ in inert gas, heat resistance to 2000 ℃ in neutral reducing atmosphere, use temperature up to 2800 ℃ in nitrogen and argon, poor stability in an oxygen atmosphere, use temperature below 1000 ℃. Hexagonal boron nitride is insoluble in cold water and hydrolyzes very slowly when boiled, producing small amounts of boric acid and ammonia; It does not react with weak acids or strong bases at room temperature and is slightly soluble in hot acids. It can be decomposed only after being treated with molten sodium hydroxide or potassium hydroxide. The expansion coefficient of hexagonal boron nitride is equivalent to that of quartz, but its thermal conductivity is ten times that of quartz. BN is both a good conductor of heat and an insulator of electricity. Its breakdown voltage is 4-5 times alumina's, and its dielectric constant is 1/2 that of alumina. BN exhibits stable performance under ultra-high pressure and is the lightest ceramic material. Cubic BN has a sphalerite structure, high chemical stability, good thermal conductivity, and heat resistance, and its hardness is similar to that of synthetic diamonds. It is an excellent abrasive material. Compared to diamond, its most prominent advantage is that it does not react with ferrous metals at high temperatures and can be used at 1400 ℃. If you are looking for high quality, high purity and cost-effective copper oxide, or if you require the latest price of copper oxide, please feel free to email contact mis-asia.