In the process of use, the spring should be subjected to the corrosion of harmful gas and work under the condition of corrosion fatigue. Oxidation treatment can make the shell hook spring have a certain corrosion resistance.

After being oxidized, the hook spring can form a dense oxide film on the surface of steel wire, which can prevent the corrosion of gunpowder gas.

Oxidation treatment can reduce the friction of the hook spring. In the process of shooting, the hook spring is subjected to repeated stretching and compression in the chamber, and at the same time, friction is formed with the chamber and friction heat is generated, which is also one of the reasons for the early failure of the shell pulling hook spring.

After being oxidized, the micro porosity of the oxide film can store oil and lubricate the spring. The thermal conductivity of the oxide film is much lower than that of the steel wire of shell hook spring, which has better thermal protection and can prevent the early failure of shell hook spring.

After the spring has been oxidized, through more than 40 life tests, the shell pulling hook spring has not broken. The practice has proved that the use life of shell pulling hook spring can be improved by oxidizing the shell pulling hook spring.