Green silicon carbide powder for anti-corrosion coating

Silicon carbide (SiC) is a synthetic silicon carbide material that rarely exists in nature. It was discovered in 1890 through synthetic experiments. Then, people used quartz sand and petroleum coke (or anthracite) to synthesize silicon carbide through high-temperature smelting. And industrialized mass production of silicon carbide begins. As additives of thermal resistance and anti-corrosion coatings and paint, green silicon carbide powder plays an important role.

For the marine ship industry, the ship has always existed in an environment of high humidity, high salinity, and high-temperature difference with the ocean, and the anti-corrosion protection of the hull is particularly important. The use of composite anti-corrosion coatings can protect the hull or deck. These anti-corrosion paints/coatings need to have the following performance characteristics:

1. Good weather resistance and corrosion resistance

2. High physical and mechanical strength and impact resistance.

3. Good wear resistance, water resistance, and oil resistance.

4. The deflector of the aircraft carrier must also withstand the high temperature of the flames ejected by the fighter jets. Coatings need to have the ability to withstand high temperatures.

Silicon carbide has high heat resistance, wear resistance, and corrosion resistance. These excellent properties mainly come from the oxidation resistance of silicon carbide. When occurs oxidation reaction with silicon carbide, there will get a layer of SiO2 film on the surface of the crystal, and this protective film can still be maintained even at a high temperature of 1500-1600 degrees. Silicon carbide is also chemically stable in high-temperature environments and has good resistance to chemical corrosion.

In addition, the production of green silicon carbide (Green Carborundum referred to as GC) is made of quartz sand and petroleum coke. The purity of SiC is over 99%, and its hardness is higher than that of black silicon carbide. The Mohs hardness of green SiC can reach 9.4-9.5, and the wear resistance and toughness are better than black silicon carbide.

Acid pickling and water sieving process are necessary for green silicon carbide powder. Pickling is to remove impurities such as free carbon, free silicon, and other substances. When making coatings, it helps to distribute silicon carbide evenly in the coating. Green silicon carbide 2000 mesh (7 microns), 2500 mesh (5 microns) always for fluorocarbon powder coatings, anti-corrosion coatings, optical ultraviolet coatings (photosensitive UV coatings). Green silicon carbide 600 mesh (28 microns), 800 meshes (20 microns), 1000 mesh (16 microns), 1200 mesh (14 microns) for fillers in Teflon non-stick coatings.