Effect of pre-oxidation and rare earth cerium on plasma nitriding of 42CrMo steel

doi:10.13251/j.issn.0254-6051.2021.05.031

Abstract

Abstract: To solve the technical problems such as shallow nitrided layer and long production cycle, the commonly used structural steel 42CrMo was plasma nitrided by pre-oxidation and rare earth complex activated nitriding. The nitriding rate, the microstructure of the nitrided layer and surface morphologies were studied systematically by using microhardness tester, optical microscope (OM), and scanning electron microscope (SEM). The results show that the best nitriding effect can be realized by pre-oxidation at 400 ℃ for 1 h+complex activated nitriding process with 0.6 cm²/kg(cerium surface area/charging weight). Compared with that without activated nitriding, the optimized complex activated nitriding not only improves the nitriding efficiency but also eliminates vein-like nitride, reduces the hardness gradient of the nitrided layer.

Key words: plasma nitriding, nitriding rate, complex activated nitriding

CLC Number:

TG156

Li Shuangxi, Chen Lin, Wang Meitao, Yan Zhiqiang. Effect of pre-oxidation and rare earth cerium on plasma nitriding of 42CrMo steel[J]. Heat Treatment of Metals, 2021, 46(5): 186-189.

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