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

tel-00751814, version 1 - 14 Nov 2012
Table of content
INTRODUCTION____________________________________________________________________1
CHAPTER 1. DEVELOPMENT OF NANO-REINFORCED F/M STEELS_________4
I. Generation IV nuclear reactors .................................................................................. 4
II. Materials requirements and possible candidates for SFR .................................... 8
II.1. Austenitic steels ............................................................................................................. 9
II.2. Ferritic/Martensitic (F/M) steels ............................................................................... 10
II.3. Nano-reinforced steels ............................................................................................... 10
III. Elaboration process of ODS ....................................................................................... 10
III.1. Mechanical Alloying process ..................................................................................... 11
III.2. Consolidation of powder and additional TMT ........................................................ 13
III.3. Microstructure and influence of elaboration parameters ....................................... 14
a)Ferritic or ferritic/martenticitic (F/M) matrix ............................................................ 14
b)Dispersion of oxides particles ................................................................................... 16
c)Mechanism of formation of nanoparticles ................................................................. 23
d)Influence of the elaboration parameters on the microstructure of ODS .................... 25
III.4. Partial conclusion ........................................................................................................ 28
IV. Nitride Dispersion Strengthened (NDS) alloys...................................................... 30
IV.1. NDS elaboration by nitriding .................................................................................... 30
a)Principle ................................................................................................................. 30
b)NDS production since 80`s ........................................................................................ 32
c)Mechanism of formation of nitrides .......................................................................... 35
IV.2. NDS elaboration by Mechanical Alloying ................................................................ 37
IV.3. Partial conclusions ...................................................................................................... 38
V. Bibliography of Chapter 1 .......................................................................................... 39
CHAPTER 2. MATERIALS, EXPERIMENTAL AND SIMULATION
TECHNIQUES_______________________________________________________________ 46
I. Materials ....................................................................................................................... 46
I.1. ODS model alloy ............................................................................................................ 47
I.2. ODS steel ...................................................................................................................... 48
I.3. Mechanically alloyed NDS steel (MA NDS) ............................................................... 49