Carburizing and quenching heat treatment process of driven reverse gear used for transmissions

Abstract

The invention provides a carburizing and quenching heat treatment process of a driven reverse gear used for transmissions. The process comprises the following steps: 1) carburizing; 2) carbonitriding; 3) quenching; 4) cleaning; and 5) tempering. The heat treatment process has the beneficial effects that the surface of the driven reverse gear is treated by carbonitriding; and carburizing and nitriding are combined, thus improving the quality of the surface of the driven reverse gear, improving the production efficiency, reducing the energy consumption and saving the production cost.

Description

technical field [0001] The invention relates to a carburizing and quenching heat treatment process for reverse gear slave teeth used in automobile gearboxes. Background technique [0002] Automobile transmission (transmission) has the following functions: 1) Change the transmission ratio, expand the variation range of driving wheel torque and speed, so as to adapt to the frequently changing driving conditions, and at the same time make the engine operate at a favorable power (higher power and lower fuel consumption) Work under working conditions; 2) When the engine rotation direction remains unchanged, the car can run backwards; 3) Use the neutral gear to interrupt the power transmission, so that the engine can start and change gears, and it is convenient for the transmission to shift gears or perform power output; 4) Speed ​​changer is made up of speed change transmission mechanism and operating mechanism, and power take-off can also be installed when necessary. There are ...

AI Technical Summary

Problems solved by technology

However, the existing carburizing process has the following disadvantages: 1. The carburizing temperature is high, the time is long, and the energy consumption is large; 2. The deformation is large; 3. There are black structures, resulting in low hardness, reducing fatigue resistance, and reducing wear resistance resistance, shorten the service life

However, this patent only uses the carburizing method to heat-treat the gear surface, and the carburizing method is single. Due to the high carburizing carburizing potential, the austenite carbon content in the carburizing surface layer is too high, and it is easy to form austenite during the cooling and heat preservation process. During the quenching and cooling process, the carbides are easy to precipitate along the austenite grain boundaries to form network carbides, which can easily cause early cracking on the gear surface; and the high-temperature heating and cooling times of the gear are twice, superimposed Carburizing deformation and quenching deformation, so the deformation of the gear is large