Induction heating heat treatment of steel using medium frequency induction heating machine can effectively improve its strength and maintain toughness

The use of medium frequency induction heating machine for induction heating heat treatment of steel has many advantages, such as improving the surface quality of steel, improving the uniformity and stability of mechanical properties, improving the strength of steel and maintaining toughness, etc. One of the most popular is that it increases strength without reducing the toughness of steel.

According to the experiment, the induction heating quenching and tempering treatment can increase the tensile strength and yield strength at room temperature by more than 10%, and the elongation and reduction of area of the steel pipe do not change significantly. Similar results were obtained when testing the mechanical properties of 40MnMoB, 40Mn2Mo, and 40Cr steel pipes.

Induction heating rapid heat treatment also has a good effect on the high temperature strength of steel. Table 1 shows the comparative test results of the high-temperature durability strength of superheater steel pipes for power station boilers using a medium-frequency induction heating machine for induction heating normalizing treatment and traditional electric furnace normalizing treatment. From the durable fracture time in Table 1, it can be seen that the durable fracture time of the same tempered steel after induction heating and normalizing is 4 times different. It fully demonstrates that induction heating and normalizing treatment can significantly improve the high-temperature durable strength of heat-strength steel. Similarly, Table 2 shows the effect of induction heating solution treatment on the high temperature durability of valve steel 21-4N. It can be seen from the durable fracture time in Table 2 that the durable fracture time of induction heating solution treatment after aging treatment under the same conditions is 1 times that of electric furnace heating solution treatment.

Table 1 Comparison of high-temperature durability strength of heat-strength steel 12Cr2WMoVTiB

Table 2 Comparison of high temperature durability strength of valve steel 21-4N

In summary, induction heating rapid heat treatment is an effective method to improve the strength of steel without reducing its toughness. This heat treatment method should be strongly advocated by us.