Co3N steel cutting blades are quenched and heat treated using high-frequency induction heating power supply

A cutting blade literally means a blade used to cut things. It is also a type of cutting tool. It has to withstand huge friction during work, so we need to perform quenching heat treatment on the cutting blade to improve its hardness, wear resistance and service life.

The outer dimensions of W8M05Cr4VCo3N (Co3N for short) cutting blade are 200mmx20mmX2mm, the required hardness is 66-68HRC, and the straightness error is <0.15mm. The blade is prone to distortion and has a low pass rate. Even if isothermal quenching is used, the pass rate is only 11%. Therefore, we switched to the induction quenching method, that is, using high-frequency induction heating power for induction quenching heat treatment, which not only makes the hardness meet the requirements, but more importantly, effectively solves the deformation problem.

1)Quenching. A high-frequency induction heating power supply is used for quenching heat treatment, first preheating at 840°C, and then heating at 1225°C, and the grain size is controlled at 9.5-10 levels.

2) Tempering. Install the quenched blade with clean residual salt on a specially tightened fixture, then flatten the blade with a pressure of 200 to 220kN on a hydraulic press, and tighten the screws. Then temper in nitrate salt 4 times, once at 550℃x30min. After tempering, take out the clamp, apply pressure while it is hot, tighten the screws again, put it back in nitrate salt at 550℃, continue tempering for 1 hour, and air cool to room temperature. During the 2nd, 3rd, and 4th tempering, loosen the clamp to clean out the nitrate and oxide scale before each tempering, reinstall the clamp and press it with a hydraulic press, tighten the screws, and proceed with tempering.

After processing according to the above process, the hardness is 67-68HRC, and the bending pass rate reaches more than 95%, which effectively solves the quenching and bending problem of mass production of such slender blades. Therefore, this process is widely used in the heat treatment of cutting blades.

Regardless of any workpiece, its heat treatment process is very important. This article briefly introduces the high-frequency heat treatment process of cutting blades. I hope it will be helpful to your work. In fact, this article does not describe the heat treatment process of the cutting blade in detail, so it is up to you to explore it yourself.