Defects and preventive measures caused when files are heat treated with ultrasonic induction heating power supply

The file is a common bench tool used for burring and grinding metal surfaces, and can also be used to cut saw blades. In order to improve its friction and service life, we will use ultrasonic induction heating power to perform heat treatment such as quenching on the file. So, what defects will occur during heat treatment? Faced with this defect, how should we solve it?

1. The depth of the hardened layer is unqualified, reducing its service life and wear resistance. The reason for this defect is that the cooling water temperature is high during quenching, resulting in poor cooling capacity or high outlet water temperature, but the surface is not hardened. We should strictly implement the correct process parameters and conduct quality inspections.

2. The hardness does not meet the requirements. If the hardness of the file is too high or too low during heat treatment and does not meet the requirements, it will cause poor wear resistance of the workpiece and reduce its service life. The causes and measures are as follows:

(1) Water is discharged too early during quenching and cooling, causing self-tempering and reducing surface hardness. Therefore, the cooling time should be strictly controlled during quenching and cooling.

(2) There is no protection during spheroidizing annealing, causing the surface decarburization depth to exceed the grinding allowance. Therefore, we need to perform protective heating annealing to ensure that the decarburization layer is less than 1/2 of the machining allowance.

3. Quenching cracking or breaking. If the workpiece cracks or breaks due to quenching, the workpiece will be scrapped and cannot be used. Causes and measures:

(1) The hardness is too high and the toughness is poor. We should control the temperature of the outlet water and cool it to 140~180℃ for thermal straightening.

(2) If the cooling time in water is too long, it will easily break during alignment. We should determine a reasonable cooling time to ensure that thermoplasticity is used for alignment.

4. The metallographic structure is unqualified, the workpiece is brittle and prone to chipping. Causes and measures:

(1) The existing continuous network carbide has not been completely eliminated. For the excessive network carbide file, normalize the gear.

(2) The quenching temperature is high or the holding time is too long, resulting in excessive martensite levels. We should strictly control and implement the correct quenching process.

Zhengzhou Gou's is a manufacturer specializing in the production and sales of induction heating equipment. The ultrasonic induction heating equipment produced has complete functions, simple operation, and fast heating speed. The equipment has a large share in the domestic market and foreign markets. If you are interested in such equipment, and if you want to know more about the heat treatment of induction heating equipment, please call us.