Surface Treatment Of Auto Parts

With the rapid development of the automobile industry, people have put forward higher and higher requirements on the ability to resist the effects of external environment and the reliability, stability and corrosion resistance of the automobile in long-term operation and the appearance of the car.

Every finished car leaves the factory all require metal surface treatment. In addition to the well-known pistons, piston rings, connecting rods and other automobile engine moving parts that need to be electroplated, bearing bushing, inlet and exhaust valve, exhaust tube, silencer, shock absorber connecting rod and other parts need to be surface treatment, automobile decorative parts also through the surface treatment to improve the beauty.

Common surface treatment methods for automobiles:
(1)Electrochemical treatment: electroplating, anodizing.
(2)Paint coating: spray painting, electrophoresis.
(3)Chemical treatment: phosphating, passivation, black oxide, etc.
(4)Heat treatment: Hot dip plating, thermal spraying, hot stamping, chemical heat treatment, etc.
(5)Vacuum process: Evaporation coating, sputtering deposition, ion plating, etc.

Electroplating technology is a necessary guarantee for the quality of auto parts. Electroplating of auto parts is divided into three categories according to their functions:
(1)Protective plating coatings: Also known as corrosion resistance electroplating, the parts themselves are required to have good corrosion resistance. It accounts for 70%~80% of the total area of automotive electroplating, such as zinc plating, zinc alloy plating, lead plating, etc.
(2)Protective decorative coating: The automotive industry has very strict requirements for protective decorative coatings. After electroplating, the appearance required to be bright, the color is uniform and coordinated, and good corrosion resistance. The coating requirements for 5 to 10 years without discoloration and corrosion, such as copper plating, imitation gold, copper+nickel+chrome etc.
(3)Functional plating: Functional plating is different from the first two electroplating, mainly to give the base material with special physical and chemical properties, focusing on the characteristics of the coating itself. Such as terne metal, hard chrome plating, tin plating, etc.