Etude par Sonde Atomique Tomographique de la formation de nano ...

tel-00751814, version 1 - 14 Nov 2012
Chapter 4. Nitride Dispersion Strengthened Steels
particle, forming the shell if solute depletion rate from the core is greater than solute
diffusion rate from the oxide/matrix interface during the crystallization stage.
Such mechanism could also occurs during MA in NDS steel. This could explain why there is
no evidence of Cr shell in as-milled samples.
a)
b)
Figure 4.23. Evolution of concentration of (a) Ti+N (at.%) and (b) Cr measured in
MA NDS steel as a function of Guinier radius (Rg). Hot extruded condition (h.e.) is also
taken into account. Guinier Radius (x axis) is shown in logarithmic scale.
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