Why isn Silicon Carbide abrasive used?
Silicon carbide is a sharp abrasive but breaks down very quickly. It then burnishes the tool rather than abrading it. This burnishing creases friction heat which can damage the tool’s temper. This is easily demonstrated with two progressively smaller Silicon carbide abrasive sheets. Rub a steel tool on a piece of this abrasive paper, such as 400 grit. After working the tool for a short time, the tool will begin to shine. Next, rub the same tool area once or twice on a new piece of 500 grit paper. Note the scratches on the area that had been shining. The fresh but finer grit was abrading the area that had been burnished by the previous grit. A sharp tool is created by abrading the meeting edges of a tool to finely finished surfaces, not by buffing them till they are shiny. Silicon Carbide abrasive does not hold up as well as Aluminum Oxide. Silicon Carbide may be used successfully for abrading aluminum and other soft materials.
