Carburizing method for parking pawl of automobile gearbox

Abstract

The invention provides a carburizing method for a parking pawl of an automobile gearbox, comprising the following steps: 1) subjecting the workpiece to an equal temperature treatment for 10 minutes at a temperature T=890-910° C. and a carbon potential of 0.6% C; 2) Raise the carbon potential to 1.05%C; 3) Under the carbon potential environment of 1.05%C, carry out strong carburizing on the workpiece for 150-210 minutes; 4) Decrease the carbon potential to 0.75%C; 5) In the carbon potential environment of 0.75%C 6) Under the carbon potential environment of 0.75%C, the workpiece is cooled to 840°C; 7) Under the constant temperature of 840°C and the carbon potential environment of 0.75%C, the workpiece is kept warm for 60 minute. The carburizing method of the parking pawl of the automobile gearbox according to the present invention makes the carburizing and quenching process of the parking pawl of the automobile gearbox short in time and high in heat treatment efficiency; it also makes the parking pawl of the automobile gearbox have good surface quality and high strength High, good wear resistance.

Description

technical field [0001] The invention relates to the technical field of heat treatment of steel workpieces, in particular to a carburizing method for a parking pawl of an automobile gearbox. Background technique [0002] Such as figure 1 As shown, the car gearbox parking pawl 1 is an important part to protect the safe parking of the car. When the car is parked, the part is locked by the operating handle to lock the transmission parts of the car, so that the car can be parked safely and reliably. Therefore, the parking pawl 1 of the automobile transmission should have sufficient strength and wear resistance, and considering the economic cost, the parking pawl 1 of the automobile transmission often uses low-carbon steel as a raw material. And quenching process to improve strength and surface wear resistance. [0003] According to the actual use, the surface hardness of the parking pawl 1 of the automobile gearbox should preferably be kept at 78.5-81HRA, the core hardness shou...

AI Technical Summary

Problems solved by technology

[0004] The carburizing process of the parking pawl of the automobile gearbox in the prior art has many types, and the value intervals of temperature, carbon potential and time are all very large, resulting in the strength, The wear resistance is uneven, and the surface quality of the parking pawl of the automobile gearbox after carburizing and quenching often fails to meet the requirements. For example, the carburizing layer is too thin or too thick, the deformation is too large, the surface hardness is too high or too low, and the surface Metallographic structure is poor

There are also some carburizing processes to make the surface quality of the parking pawl of the automobile gearbox good, but the carburizing process takes too long, so that the heat treatment efficiency of the parking pawl of the automobile gearbox is too low and the production efficiency is low

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