Paper Title:
Unusual Microstructural Development upon Gaseous Nitriding of Fe-4.65at% Al Alloy
  Abstract

Employing NH3/H2 gas mixtures, Fe-4.65at% Al alloy specimens were nitrided to assess how the presence of Al, originally dissolved in the ferrite matrix, influences the development of γ-Fe4N1-x phase in the surface adjacent region. The nitrided specimens were characterized by light microscopy, X-ray diffraction, Electron Backscatter Diffraction and Electron Probe Micro Analysis. Surprisingly, formation of ε-Fe2N1-x was observed, although, for the applied nitriding parameters (nitriding potential and temperature), only the formation of γ-Fe4N1-x would be expected in case of nitriding pure ferrite. An unusual plate-type morphology of γ-Fe4N1-x was observed, contrasting with the usual continuous layer-type growth observed upon nitriding iron, Fe-Cr and Fe-V alloys. These unexpected phenomena may be explained as consequences of the need to realize a very high nitrogen supersaturation in the ferrite matrix in order to initiate the precipitation of AlN.

  Info
Periodical
Advanced Materials Research (Volumes 89-91)
Edited by
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
Pages
371-376
DOI
10.4028/www.scientific.net/AMR.89-91.371
Citation
S. Meka, R.E. Schacherl, E. Bischoff, E. J. Mittemeijer, "Unusual Microstructural Development upon Gaseous Nitriding of Fe-4.65at% Al Alloy", Advanced Materials Research, Vols. 89-91, pp. 371-376, 2010
Online since
January 2010
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Tatiana Liapina, Andreas Leineweber, Eric J. Mittemeijer
Abstract:ε/γ'-iron nitride (ε-Fe3N1+x, γ'-Fe4N) compound layers with thicknesses of about 10 µm were grown on pure α-Fe by gas nitriding at 823 K...
1147
Authors: M. Wohlschlögel, W. Baumann, U. Welzel, Eric J. Mittemeijer
Abstract:Stress gradients have been investigated employing a measurement strategy for diffraction measurements at constant penetration/information...
19
Authors: Sebastien Jegou, Regis Kubler, Laurent Barrallier
Abstract:This work deals with the development of residual stresses during nitriding of steels. The main features of a chemico-thermo-echanical model...
256
Authors: Rico Bauer, E. Bischoff, Eric J. Mittemeijer
Abstract:Natural formation of the unusual bcc modification for Co was demonstrated to occur upon precipitation of Co in supersaturated...
390
Authors: R.E. Schacherl, Eric J. Mittemeijer
Chapter 20: Surface Engineering & Coatings
Abstract:For the first time it could be shown that, upon nitriding Fe-Cr-Al alloys, the thermodynamical stable cubic CrN and hexagonal AlN nitrides do...
2583