Common materials of gears

The steels commonly used in manufacturing gears are quenched and tempered steel, hardened steel, carburized and hardened steel and nitrided steel. The strength of cast steel is slightly lower than that of forged steel, and it is often used for larger gears. Gray cast iron has poor mechanical properties and can be used for light load open gear transmission. Ductile iron can partially replace steel to make gears; Plastic gears are mostly used in places with light load and low noise requirements, and the matching gears are generally steel gears with good thermal conductivity.

In the future, gears are developing in the direction of heavy load, high speed, high precision and high efficiency, striving for small size, light weight, long service life, economy and reliability.

The development of gear theory and manufacturing technology will further study the mechanism of gear tooth damage, which is the basis for establishing a reliable strength calculation method and the theoretical basis for improving gear bearing capacity and prolonging gear life. Develop a new tooth profile represented by circular arc tooth profile; Research on new gear materials and new gear manufacturing technology: The elastic deformation, manufacturing and installation errors and temperature field distribution of gears are studied, and the gear teeth are modified to improve the stability of gear operation and increase the contact area of gear teeth when fully loaded, thus improving the bearing capacity of gears.

Friction, lubrication theory and lubrication technology are the basic work of gear research. Studying the theory of elastohydrodynamic lubrication, popularizing the use of synthetic lubricating oil and adding extreme pressure additives to the oil can not only improve the bearing capacity of the tooth surface, but also improve the transmission efficiency.