Chemical nickel plating, also known as autocatalytic nickel plating, is a chemical process that forms a uniform, dense nickel coating on the surface of a metallic or non-metallic substrate without the need for an applied current. The technology is based on the reduction reaction of metal ions in solution, and the automatic deposition of nickel ions is achieved by controlling the components such as reducing agent, buffer and activator in the solution. Compared with conventional electroplating, electroless nickel plating does not require complex equipment, can be performed at room temperature, and is more applicable to a wider range of substrates, including stainless steel, aluminium alloys and plastics. These characteristics give chemical nickel plating a significant advantage in applications such as wear, corrosion and fatigue resistance. Especially in the field of precision instruments, aerospace and medical devices, the high uniformity and functionality of its plating becomes an indispensable technical support.