Microstructure homogenization of 17CrNiMo6 gear steel

doi:10.13251/j.issn.0254-6051.2022.11.022

Abstract

Abstract: Taking 17CrNiMo6 gear steel as the research object, and the forged specimens were annealed at different temperatures for different time. The formation of the banded structure and its homogenization behavior were studied and quantitatively analyzed by means of optical microscope, scanning electron microscope, energy dispersive spectrometer and data processing software Origin. The results show that the enrichment of C, Cr, Ni, Mn and Mo in the pearlite+bainite region is the root cause of the band structure of the 17CrNiMo6 gear steel. When the heating temperature is 1100 ℃ with the holding time of 11 h, or the heating temperature is 1250 ℃ with the holding time being more than 2 h, the banded structure is eliminated, but the non-uniformity of alloy elements is still high. When the heating temperature is 1250 ℃ and the holding time is 4 h, the segregation coefficients K for C, Cr, Mn, Ni, P, S, Mo are 1.02, 0.98, 1.02, 1.02, 1.01, 0.98, and 0.98, respectively, and the element distribution is also uniform.

Key words: 17CrNiMo6 gear steel, element segregation, banded structure, homogenization behavior

CLC Number:

TG156.2

Wang Jie, Dang Shue, Fan Zijing, Guo Lun, Zhu Xuetong. Microstructure homogenization of 17CrNiMo6 gear steel[J]. Heat Treatment of Metals, 2022, 47(11): 126-133.

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