The nib ball needs to be made of hard and wear-resistant materials. The most commonly used materials are stainless steel and tungsten carbide, the latter of which is of better quality. Tungsten carbide is a compound composed of tungsten and carbon. It is a cemented carbide production material. It is a black hexagonal crystal with a hardness similar to that of diamond. It has stable chemical properties and is a good conductor of electricity and heat.
