The steels commonly used in the manufacture of gears are quenched and tempered steel, quenched steel, carburized and quenched steel and nitrided steel. The strength of cast steel is slightly lower than that of forged steel, and is often used for gears with larger sizes; gray cast iron has poor mechanical properties and can be used in light-load open gear transmissions; ductile iron can partially replace steel to make gears; plastic gears are mostly used In places where light loads and low noise are required, steel gears with good thermal conductivity are generally used for their matching gears.
In the future, gears are developing in the direction of heavy load, high speed, high precision and high efficiency, and strive to be small in size, light in weight, long in life and economical and reliable.
The development of gear theory and manufacturing process will further study the mechanism of gear tooth damage, which is the basis for establishing a reliable strength calculation method, and is the theoretical basis for improving gear bearing capacity and prolonging gear life; the development is represented by arc tooth profile. new gear shape; research new gear materials and new gear manufacturing process; research gear elastic deformation, manufacturing and installation errors and distribution of temperature field, gear teeth modification, to improve the smoothness of gear operation, and at full load At the same time, the contact area of the gear teeth is increased, thereby improving the bearing capacity of the gear.
Friction, lubrication theory and lubrication technology are the basic work in gear research. Studying elastic hydrodynamic lubrication theory, promoting 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 It can also improve transmission efficiency.
