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Presently, the roller hearth furnaces were most commonly used when heating blanks during hot stamping process. The production cost was evidently increased because of its body length, occupied area and great investment. A limitation of production efficiency can be easily imagined when using roller hearth furnace heating blanks rapidly. If rapid heating process was implemented, such as can induction heating or resistance heating, the disadvantages can be solved easily. Meanwhile, rapid heating prevent the oxidation layer from forming due to its high heating rate.

The current experiment simulates the scale evolving results of 22MnB5 with different reheating temperatures and holding time during rapid induction heating process. The section morphology of the scales was investigated carefully by SEM and EDX. After that we measured the increased weight of the heated sample with electronic balance. With the experimental data the thickness of the scales based on the oxidation kinetics model could be finally calculated. As a result, the thickness of the scales increased with holding time at the same reheating temperature, while a parabolic-linear tendency appeared since temperature increased with same hold time.

By continuous high temperature oxidation experiment, oxidation kinetic curve was obtained, combined with X-ray diffraction analysis, scanning electron microscope(SEM) along with chemical microanalysis by energy dispersive spectrometry(EDS), We systematic studied the oxidation performance and law of ZG40Cr25Ni20 in high temperature. The result showed that between 900℃ and 1000℃, it exhibited a good oxidation resistance ,the surface was covered with a compact protective scale Cr₂O₃ and MnCr₂O₄..However,when the temperature was up to 1100 ℃, the oxidation performance was severe, the oxidation scale contain NiCr₂O₄ and Fe₃O₄.