The screw shaft is a central screw structure consisting of a cylinder, a central shaft and blades. Due to the rotation of the spiral blades, the material moves in a certain direction and can transport materials with a certain friction force. , which has good resistance to earth pressure and control. The ability of earth pressure to ease during transportation and maintain the dynamic balance of earth pressure requires the screw shaft to have high anti-corrosion and wear-resistant properties. Plasma spraying ceramic coating on the screw shaft can effectively increase the service life of the screw shaft.

Among ceramic oxide coatings, alumina is one of the most commonly used and widely used varieties. Plasma sprayed alumina ceramic coatings are widely used in industry. The use of plasma spraying of ceramic coatings to obtain structural composite coatings and functionally graded coatings is one of the hot research areas at home and abroad to study the microstructure, wear resistance, corrosion resistance and high-temperature oxidation resistance of ceramic coatings.

The cost of the screw shaft is very high, and it is the main wearing part. It is repaired by ceramic coating plasma spraying, and its original function can be restored after using wear-resistant alloy powder for manufacturing. The wear-resistant and corrosion-resistant properties are improved, recycling is realized, production and maintenance costs are reduced.

Ceramic coating has higher adhesion and more stable chemical properties. It is widely used in iron and steel industry, electric power industry, glass industry, paper printing industry, petrochemical industry, automobile manufacturing, mold making and other industries, and can also bring defective parts. it can also be strengthened and protected in the production of new products, and is an important additive manufacturing technology.