Coating category	Coating characteristics and use environment	Coating thickness	Salt Spray Test time
White Znic/Black Zinc plated	Zinc is a non-magnetic material, suitable for use inside the product. There is no strict salt spray test requirement, just as a decorative property, and it is generally used inside the product. The magnet is not exposed to the air.	3-5μm	No Standard Salt Spray Test
Colorful Zinc/Blue Zinc plated	Compared with white zinc, its anti-corrosion ability is obviously improved. It can pass the salt spray test for 24 hours when used in a relatively harsh environment.	6-12μm	24 hours
Nickel plated	The coating has a strong ability to withstand high-pressure accelerated aging tests. Suitable for the use of magnets exposed to room temperature and dry environment.	6-8μm	No Standard Salt Spray Test
Nickel-Copper- Nickel(NiCuNi)/Ni-Cu-Ni- Black Ni plated	Compared with single-layer nickel, it has better corrosion resistance, but the process is relatively complicated and the electroplating time will be longer.	10-16 μm	24-48 hours
Nickel- Copper-Nickel- Sliver plated	t has good decoration, the surface is not easy to change color, and the cost is high. It is used for products or occasions with strong decorative appearance. Salt spray resistance test is the same as NiCuNi	10-18μm	24-48 hours
Nickel- Copper-Nickel-Au plated	It has good decoration, the surface is not easy to change color, and the cost is high. It is used for products or occasions with strong decorative appearance. Salt spray resistance test is the same as NiCuNi	10-25 μm	24-48 hours
Chemical Nickel	Good corrosion resistance, the cost is high, suitable for products that are harsher to the environment.	10-30μm	96 hours
Epoxy plated	Generally the coating is black, the cost is high, with good corrosion resistance, suitable for humid environment	10-30μm	96 hours