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

tel-00751814, version 1 - 14 Nov 2012
(a) 160×14×14 nm (b)
3
Isolated nanoparticles
(1)
Chapter 3. Oxide Dispersion Strengthened Steels
Figure 3.11. 3D reconstructions of ODS steel studied by LATAP in (a) as-milled, (b)
annealed at 850°C during 1h and (c) hot extruded condition. Cr, W, Ti, TiO, Y, YO, O, FeO,
CrO species are shown. In all cases distributions of Y, YO, O, FeO and CrO are associated
with nanoparticles. Isolated nanoparticles using a cluster detection algorithm are also shown.
Zooms on particles indicated by arrows (1, 2, 3) are depicted respectively on Figure 3.12.
10×10×10 nm 3
(c)
Isolated nanoparticles
Cr
W
Ti, TiO/O
Y, YO, O
CrO, FeO
90×14×14 nm 3
116×11×11 nm 3
(1) (2)
(3)
Figure 3.12. Zoom on a typical particles detected by APT in ODS steel (1) in as-milled
state, (2) after annealing at 850°C during 1h and (3) in hot extruded state. Cr and Fe atoms
are represented in black, W in orange, CrO and FeO in blue, Ti and TiO in pink and Y, YO
and O in red. Solute atoms in the matrix are represented by spheres with relative size equal to
1 and solute atoms in the nanoparticles by spheres of the relative size equal to 4. (Cr and Fe
are represented as dots). Volume of 10×10×10 nm 3 is shown for each particle.
(3)
Isolated nanoparticles
Cr
W
Ti, TiO
Y, YO, O
CrO, FeO
(2)
Cr
W
Ti, TiO
Y, YO, O
CrO, FeO
111