By increasing the current density, the grains of the chrome-plated layer can be made finer, thereby improving the hardness. However, it should be noted that excessively high current density may cause the surface of the coating to be rough or cracked, so fine adjustment is required.

Mechanical polishing is to remove oxides from the surface of chrome-plated rollers through mechanical force. This method is simple to operate and can quickly remove surface oxides and restore the finish of the roller.

During the electroplating process, if the thickness of the chrome layer is uneven, the weak part will become a stress concentration point, which is prone to cracks during use. This situation is particularly common at the edges or concave and convex parts of the roller.