Views:6 Author:Site Editor Publish Time: 2022-01-11 Origin:Site
Because the molecular structure characteristics of hexagonal boron nitride, so it has many excellent properties, such as high thermal conductivity, high heat resistance, good lubricity, low friction coefficient, low thermal expansion coefficient, excellent dielectric properties and other physical properties, it also has the strong oxidation resistance, corrosion resistance is strong, stable chemical properties and chemical properties.
1. High heat resistance. Hexagonal boron nitride (H-BN) will sublimate when heated to 3000℃ or above in 0.1mpa nitrogen. Its strength at 1800℃ is 2 times that of room temperature, so it has excellent thermal shock resistance. It will not break when air-cooled to room temperature for dozens of times at 1500℃.
2. High thermal conductivity. The thermal conductivity of hexagonal boron nitride products is about 33W/m· K, with similar thermal conductivity with stainless steel, the thermal conductivity is larger.
3. Low expansion coefficient. Hexagonal boron nitride linear expansion coefficient is (2.0~6.5) *10-6/℃, second only to quartz glass, coupled with its high thermal conductivity, so the thermal shock resistance is excellent.
4. Excellent electrical insulation. Hexagonal boron nitride has good insulation at high temperature, and the maximum volume resistivity of high purity hexagonal boron nitride can reach 1016~1018 ω •cm, even at 1000℃, there are still 104~106 ω •cm.
5. Good corrosion resistance. Hexagonal boron nitride has good chemical stability and is not wetted by most molten metals, glass and salts, so it has high resistance to acid, alkali, molten metals and glass erosion, and has good chemical inertia.
6. Low friction coefficient. Hexagonal boron nitride has excellent lubrication performance, friction coefficient is 0.16, does not increase at high temperature, higher temperature resistance than molybdenum disulfide, graphite, oxidation atmosphere can be used to 900℃, vacuum can be used to 2000℃.
7. Machinability. Hexagonal boron nitride is easy to finish with conventional metal cutting techniques, with turning accuracy up to 0.05mm, so complex shaped products can be machined from hexagonal boron nitride blanks.