Siliconized graphite is a composite material in which silicon carbide is attached to the surface of a graphite substrate. It has the characteristics of high hardness, high mechanical strength and wear resistance of silicon carbide, as well as the self-lubricating properties and thermal shock resistance of graphite. It is an ideal friction materials and mechanical seal materials, suitable for mechanical sealing of various water pumps, oil pumps, chemical pumps, and bearings of various high-speed and high-load main pumps. In addition, siliconized graphite has good oxidation resistance, thermal shock resistance, low porosity, and certain electrical conductivity, and can be used as materials such as metal smelting crucibles and draft tubes.
The composition of siliconized graphite is uniform, the surface is consistent with the inside, and the composition ratio of silicon carbide and graphite is adjustable. The higher the content of silicon carbide, the greater the density of the material, the higher the compressive strength, and the resistivity increases.
Metallographic picture of siliconized graphite
(the black part is graphite, the gray part is silicon carbide, and the white part is silicon)
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硅化石墨主要技术指标 |
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类别 Item |
指标 Value |
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密度 Density |
2.4-2.9g/cm³ |
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孔隙率 Porosity |
<0.5% |
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抗压强度Compressive strength |
>400MPa |
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抗折强度 Flexural strength Flexural strength |
>120MPa |
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热导率 Thermal conductivity |
120W/mK |
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热膨胀系数Thermal expansion coefficient |
4.5×10-6 |
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弹性模量Elastic modulus |
120GPa |
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冲击强度Impact strength |
1.9KJ/m² |
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水润滑摩擦系数 Water lubricated friction |
0.005 |
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干摩擦系数Dry friction coefficient |
0.05 |
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化学稳定性 Chemical stability |
各种盐，有机溶剂，强酸(HF,HCl,H₂SO4,HNO₃) Various salts, organic solvents, strong acids (HF,HCl,H₂SO4,HNO₃) |
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长期稳定使用温度 Long-term stable use temperature |
800℃(氧化气氛), 2300℃(惰性或真空气氛) 800℃(oxidizing atmosphere), 2300℃(inert or vacuum atmosphere) |
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电阻率 Electrical resistivity |
120×10-6Ωm |
