Control of white layer porosity in gas nitrocarburizing

doi:10.13251/j.issn.0254-6051.2023.11.028

Abstract

Abstract: Porosity in white layer is an important factor which affects its performance during gas nitrocarburizing, and the most important mechanism of porosity formation is the decomposition of nitrides and the recombination of atomic nitrogen to molecular nitrogen. The formation of porosity is related to the material, gas nitrocarburizing time and temperature, and the concentrations of nitrogen and carbon in the white layer which are directly related to the nitrogen potential K_N and carbon potential K_C values of the atmosphere. In a typical nitrocarburizing process, the control of white layer porosity is throughout the process, including all the heating, holding and cooling stages.

Key words: nitrocarburizing, recombination, K_N, K_C, porosity

CLC Number:

TG156.8⁺2

Wang Jianxin, Wu Kai. Control of white layer porosity in gas nitrocarburizing[J]. Heat Treatment of Metals, 2023, 48(11): 180-184.

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