The ballpoint pen is a pen that brings out the writing medium by rolling the ball at the front end of the pen or refill.
A ballpoint pen is a pen that uses tiny rotating balls, some of which are made of brass, steel, or tungsten carbide, and can release ink onto the paper when writing. Ballpoint pens are very different from their predecessors, reed pens, feather pens, metal-tip pens, and fountain pens.
The round ball of the nib needs to be made of hard and wear-resistant materials. The most commonly used materials are stainless steel and tungsten carbide, the latter being of better quality. Tungsten carbide is a compound composed of tungsten and carbon. It is a hard alloy production material. It is a black hexagonal crystal with a hardness similar to diamond. It has stable chemical properties and is a good conductor of electricity and heat.
Every small deviation in the production of a ballpoint pen will affect the fluency and service life of the pen tip. The thickness of the opening of the pen tip is less than 0.1 mm, and the writing angle and pressure must also be taken into consideration. "It is seamless", and the processing error cannot exceed 0.003 mm.