2849.20 - Of silicon:

This HTS category, 2849.20, specifically encompasses carbides of silicon. Silicon carbide, also known as carborundum, is a synthetic chemical compound with exceptional hardness and thermal conductivity. It is widely used in abrasives, refractory materials, and increasingly in high-performance electronic components due to its semiconductor properties. The classification focuses on the material itself rather than finished articles made from silicon carbide.

Within the broader category of "Carbides, whether or not chemically defined," 2849.20 distinguishes itself from its sibling, 2849.10 (Carbides of calcium). While both are carbides, the key differentiator is the primary elemental composition: silicon for 2849.20 versus calcium for 2849.10. Other carbides fall under the residual category of 2849.90.

This classification is further refined by its subcategories, which differentiate based on the physical form of the silicon carbide. 2849.20.10.00 covers crude silicon carbide, typically in its raw, unprocessed state as produced from the electric furnace. In contrast, 2849.20.20.00 includes silicon carbide that has undergone further processing, such as being formed into grains, ground, pulverized, or refined into a purer form. These distinctions are crucial for import and export declarations, reflecting different stages of manufacturing and potential applications.