Molybdenum is an refractory metal with a melting point of 2630℃ and recrystallization temperature of about 900℃. At high temperature, it has high strength and good processing performance. It is not only a heat-resistant coating material, but also a * metal material with heat-resistant hydrochloric acid. Molybdenum has low friction coefficient and good wear resistance.
When spraying molybdenum, surface molten molybdenum can be dissolved into the metal matrix, even in the cutting of smooth workpiece surface metallurgical bonding, bonding layer thickness of about 1 micron so it is also commonly used as a substrate material. Molybdenum can form a good combination with many metals, such as ordinary carbon steel, stainless steel, cast iron, aluminum and its alloy. Therefore, molybdenum coating is often used as the base layer for the coating of machine tool bed guide rail.
In addition, some MoS2 impurities will remain in molybdenum coating, or react with sulfur to form MoS2 solid lubrication film, so molybdenum coating can be used as wear resistant coating, such as working spray layer of piston ring, brake pad, aluminum alloy cylinder and other friction surfaces.
Molybdenum spraying, mostly using flame wire spraying, because of the low cost, simple operation, easy to achieve automation. Molybdenum powder sprayed by plasma has the advantages of dense coating and low oxide content, and molybdenum powder can be mixed with other powder materials, which creates favorable conditions for molybdenum powder sprayed by plasma.
The main disadvantage of molybdenum is that it is easy to be oxidized. Its oxide (MoO3) has a low melting point (about 780 degrees) and is volatile. Therefore, it will be rapidly oxidized when it is higher than the melting point.
