Effect of Pulsed Magnetic Field on Quenched Heat Treatment of GCr15 Steel

The dissolution behavior and dislocation proliferation of carbides during the quenching process of GCr15 steel are studied respectively under a single temperature field and a magnetic-thermal coupling field. The morphology of carbides was observed by using scanning electron microscopy, the hardness of specimens was tested by Vickers hardness tester, the surface residual stress of specimens was tested by XRD strain gauge, and the dislocation density of specimens was tested by XRD diffractometer under both single temperature field and magnetic-thermal coupling field. The results show that the pulsed magnetic field is beneficial to the dissolution of carbides during the quenching austenite transition of GCr15 steel, and the number of undissolved carbide particles from 68.4 x 10(-2) mu m(-2) in a single temperature field decreases to 38 x 10(-2) mu m(-2), and the dislocation density increases from 296.4 x 10(10) m(-2) under a single temperature field to 358.8 x 10(10) m(-2) with an 20.1% increase by applying pulsed magnetic field. From the kinetics theory, it is believed that the frequency of carbon atoms migrating to the gap position increases; thereby the diffusion coefficient D-0 increases, and the diffusion of carbon atoms in the matrix is accelerated by employing a pulsed magnetic field.

Automated summary

The dissolution behavior of carbides and the proliferation of dislocations during the quenching process of GCr15 steel were studied under single temperature field and magnetic-thermal coupling field. The results showed that the pulsed magnetic field aided in the dissolution of carbides, reducing the number of undissolved carbide particles and increasing the dislocation density. According to the kinetics theory, the migration frequency of carbon atoms to the gap position increased, leading to an accelerated diffusion of carbon atoms in the matrix when a pulsed magnetic field was applied.