Black silicon carbide, also known as silicon carbide black, is a type of silicon carbide material with the following characteristics and applications:
Properties
- High hardness：Its hardness is between corundum and diamond, with a Mohs hardness of about 9.5, second only to diamond. It has excellent wear resistance and can maintain its shape and sharpness during use13.
- High temperature resistance：It can maintain good stability at high temperatures and has a high melting point and boiling point. It is suitable for use in high-temperature environments and can resist the erosion of high-temperature gases and molten metals.
- Good chemical stability：It has strong resistance to acids, alkalis and other chemical substances and is not easy to be corroded. It can maintain its performance and integrity in harsh chemical environments.
- High thermal conductivity：It has good thermal conductivity and can quickly transfer heat, which helps to dissipate heat in high-temperature applications and prevent local overheating234.
- Low coefficient of thermal expansion：The coefficient of thermal expansion is small, and the volume change is small when the temperature changes, which can maintain good dimensional stability and is not easy to produce cracks and deformations.
Production process
It is mainly made from raw materials such as quartz sand and petroleum coke through high-temperature smelting in an electric resistance furnace. The specific process is as follows5:
- Raw material preparation：Select high-purity quartz sand and petroleum coke as the main raw materials and carry out pretreatment such as crushing and screening to ensure the particle size and purity of the raw materials meet the requirements.
- Mixing：Mix the pretreated quartz sand and petroleum coke in a certain proportion and add appropriate additives if necessary to improve the reaction efficiency and product quality.
- High-temperature smelting：Put the mixed raw materials into an electric resistance furnace and heat them to a high temperature of about 2000°C for smelting. In the high-temperature environment, the chemical reaction between quartz sand and petroleum coke occurs to generate silicon carbide.
- Post-treatment：The obtained silicon carbide block is processed by crushing, acid-base washing, magnetic separation, screening and other processes to remove impurities and obtain black silicon carbide products of different particle sizes.
Applications
- Abrasive and grinding tools：It is widely used in the manufacturing of abrasive tools such as grinding wheels, sandpaper, abrasive belts and grinding blocks. It can be used for grinding, polishing and cutting of various materials, such as metals, ceramics, glass and stones124.
- Refractory materials：It is used to make refractory bricks, crucibles, furnace linings and other refractory products, which can improve the high-temperature resistance and wear resistance of the furnace and prolong the service life of the furnace.
- Semiconductor field：It is an important semiconductor material and can be used to manufacture high-power, high-frequency and high-temperature semiconductor devices, such as transistors, diodes and thyristors. It has excellent electrical properties and can improve the performance and reliability of semiconductor devices.
- Aerospace and military fields：Due to its high hardness, high temperature resistance and good mechanical properties, it is used in the manufacturing of aerospace parts, such as aircraft engine components, wing skins and missile shells. It can also be used to make body armor and vehicle armor to improve the protection performance.
- Chemical industry：It can be used as a catalyst carrier or a material for manufacturing chemical reaction vessels, which can resist the corrosion of chemical substances and improve the efficiency and safety of chemical reactions.