Premium
Three‐dimensional atom probe analysis of chromium‐ and copper‐added nitriding steel
Author(s) -
Takahashi J.,
Kawasaki K.,
Kawakami K.,
Sugiyama M.
Publication year - 2007
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.2520
Subject(s) - nitriding , copper , atom probe , chromium , metallurgy , materials science , nitride , precipitation , chromium nitride , layer (electronics) , microstructure , composite material , physics , meteorology
Detailed analysis of fine precipitates in a soft‐nitrided steel containing chromium and copper was performed using an energy‐compensated three‐dimensional atom probe (3DAP). A high number density of copper precipitates, chromium nitride precipitates and their pairs were observed in the diffusion layer of the nitrided steel. The size and density of these precipitates dominated the hardness increment due to nitriding. From the characteristic distribution and morphology of these precipitates in the depth direction, the following three stages of precipitation are proposed: In heat treatment for nitriding, copper precipitates are generated first. Chromium nitrides are then nucleated on the surface of the copper precipitates heterogeneously, and their pairs are formed. Finally, single chromium nitrides were homogeneously nucleated. Copyright © 2007 John Wiley & Sons, Ltd.