Brief introduction to the application of thermal spray technology in the automotive industry

       In the automotive industry, it is used for synchronizing rings, exhaust gas sensors, cylinder bores, welding of roofs, engines and tail fin systems, etc.



    (1) Synchronizing ring, there are many synchronizing rings in the automobile gearbox. After spraying a layer of liqun, the gear can have a self-locking function when it is working, so as to ensure the smoothness and stability of the driving. In front of the mouth, a large-scale production base for spraying synchronizing rings has been built in China.

    (2) Piston ring, the outer surface of the aluminum piston ring has a groove, which is in contact with the inner surface of the piston cylinder bore during operation. After spraying with a layer of aluminum powder containing Ni-Cr-B-Si by plasma spraying. Improves wear resistance of the entire component.

    (3) Exhaust gas sensor, the sensor is made of alumina from the electrolyte, shaped like a test tube, with a platinum electrode attached. In order to prevent the high temperature gas from eroding the platinum electrode, it is necessary to spray a spinel coating on the electrode, and put the exhaust gas sensor into the exhaust gas flow of the automobile. The coating can not only protect the electrode, but also allow the hot gas to reach the electrode.

    (4) Cylinder hole, cylinder hole spraying molybdenum alloy is one of the largest applications of plasma spraying in the automotive industry. At present, Sulzer Metco has developed a complete system for engine cylinders from cleaning, sand blowing to spraying, and the coating quality is the best. This system can spray 200 pieces of cylinder liners for 10-cylinder engines per day.

    (5) The connection of the roof will produce a defect area at the welding seam between the roof and the front panel of the car. The previous method to make up for this defect was to grind off the excess solder, thus reducing the strength of the welding seam. Several auto companies have now used arc spraying of silicon bronze to fill this seam area. It not only improves the appearance of the body, but also improves the weld tension.

    (6) Thermal barrier coating. The thermal barrier coating originally applied to aero-engines has been applied to automobile engines (mainly diesel engines) and exhaust systems.