1. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 1 Nanoindentation measurements and TEM observations of Ti 3 SiC 2 irradiated by charged particles X. Liu 1,2, M. Le Flem 1, J.L. Béchade 1, T. Cozzika 1, S. Doriot 1, I. Monnet 3 and Y. Zhou 2 CEA-Saclay / Nuclear Material Division CEA – Saclay Center Nuclear Material Division Section for Applied Metallurgy Research 1 Shenyang National Laboratory for Materials Science Institute of Metal Research, Chinese Academy of Sciences Shenyang, China 2 Centre Interdisciplinaire de Recherches Ions Lasers-CIRIL (CEA-CNRS-ENSICAEN) 3 High Performance Ceramics Divistion/SYNL/IMR

2. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 2 Core Components  Mechanical Integrity During the whole operating time  Chemical Compatibility with impure in He and fuel  Gas Tightness of course must neutron transprency Gas cooled fast reactor (GFR ) Normal condition : T = 600-1000°C (impurity in He) Accident condition: T = 1650°C (impurity in He) Fast neutrons : E > 0.1MeV, 1.10 27 n/m 2,60-90 dpa Future Nuclear Systems  Challenge for structural materials GFR Core Introduction (1/2) SiC f /SiC = reference Solution Ceramics TiC, ZrC, SiC, TiN, ZrN Low Toughness Refractory Metals Nb, Mo Neutron Limitation plate type fuelPin type fuel LTCs – Ti 3 SiC 2 Need of Damage Tolerant Ceramics

3. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 3 Stability under irradiation ? Stability of the layered structure  Irradiation with neutrons in progress (Phenix reactor, Osiris…)  Irradiations by charged particules (Kr, Xe...) Will give some information of irradiation effects 10 µm Introduction (2/2) Ti 3 SiC 2 : Extensively-studied Damage tolerant ceramic Plane Si TiC Good toughness because of weak bond between layers Damage tolerance even at 20°C Ductile at about 1100°C Good thermal conductivity (~TiC) Easily machinable Original investigation Very first results

4. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 4 Material Fabrication (1/1) Ti 3 Si x Al 1-x C 2 solid solution (5%,10% Al) to get pure materials and improve oxidation resistance Fabricated in IMR Shenyang, China: hot pressing of Ti + Si + C + Al power at about 1550°C Typical lamilate grain and very pure. Secondary phase <5% 10%Al Irradiation Kr 78MeV (2.10 11, 1.10 12 to 1.10 15 ions/cm 2 ) Irradiation Xe 91MeV (1.1012 to 1.1015 ions/cm2) 20°C 500°C (GANIL, Caen, France)

5. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 5 Nanoindentation : Principle and Methods To avoid Size Effect of Nano-indentation Usuaslly Constant Displacement mode was used to investigate irradiation effect We do not Know Damage profile of Ti 3 SiC 2 because the lack of threshold displacement energies of elements in Ti 3 SiC 2 SiC Damage profile in SiC (TRIM simulations) M. Le Flem et al How to select indention depth? Cross-Section nano-indentation Size Effect of Nano-indentation Example

6. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 6 Nanoindentation on cross-section to determine the thickness of damage layer Irradiation depth ~ 9µm Evolution of hardness with irradiation dose and temperature TSC10 Kr 78MeV, 1.10 12 ions/cm 2 20°C TSC10 Kr 78MeV, 1.10 15 ions/cm 2 20°C TSC10 Kr 78MeV, 1.10 15 ions/cm 2 500°C SEM image after nano-indentation 2µm P. Bonnaillie CEA/DMN/SRMP Irradiated layer Kr Irradiated layer Ni The size of print is about 5 times of Penetration depth d=150 nm, D=0.75µm, 30 Prints in each line

7. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 7 Kr SurfaceIrradiation Layer Matrix ~ 9 μm SurfaceIrradiation LayerMatrix ~ 7 μm I. Cross-Section nanoindention at depth of 150 nm Kr, 10 15 ions/cm 2, RT,Kr, 10 15 ions/cm 2, 500 o C, Ion implantation peak is between 7 and 9 μm to the surface 10% Ti 3 SiC 2

8. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 8 II. Nano-indentation at constant displacement of 1100 nm (to get hardness from peak damage region, dX7) Hardness at RT is always higher than at 500 o C Hardness is higher for 5% Al sample Hardness ia hifhwe doe Xe irradiated than Kr irradiated samples RT 500 o C Xe Kr When fluence higher than 10 13 ions/cm 2 5%Al

9. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 9 XRD for 10%Al consistent with Nano-indentation results Irradiation  Irradiation effect become apparent when dose higher than 10 13 ions/cm 2 (  microdistorsions?) 008 Peak shift to small angle,  increase of lattice parameter of c axis. Sign of recover of defects after irradiation at 500°C 10 15, 500°C 10 15, 20°C 10 14, 20°C 10 13, 20°C 10 12, 20°C virgin (10%Al) J. Pelé CEA/DMN/SRMA 404535 60 50 40 30 20 10 0 50 2θ2θ intensité 008

10. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 10 5%Al Irradiated sample 5nm Basal P lane 5%Al Virgin sample Ion impacts in some silicides secondary phases I. Irradiation at low dose (74 MeV Kr, 2.10 11 ions/cm 2, RT)

11. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 11 II. Irradiated at high dose (91 MeV Xe, 10 15 ions/cm 2, RT ) 0008 hki0 10% Al Hills Black dots, Dislocation loops?

12. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 12 SiC TiC II. Irradiated at high dose (91 MeV Xe, 10 15 ions/cm 2, RT ) No change amorphous

13. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 13 Conclusions Evalution of H is consistent with XRD (c=17,6  17,9 Å ) and TEM investigation  Short range disorder (10 11 ions/cm 2 )  large quantity of black dots (10 15 ions/cm 2 ) Nano-hardness, Increase when fluence higher than 10 13 ion/cm 2, Hardness of 5% Al samples are always higher than that of 10% Al samples, Decrease of hardness at 500 o C for the two kinds of samples  recovery of irradiation defect, High energy Xe irradiation causes more damage than Kr irradiation Prospects TEM cross section XRD diagram Rietveld analyses Irradiations at intermediate doses and temperatures Effect of post-irradiation heat treatment on defect annealing

14. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 14 TSC5 and TSC 10, Which is better? J. Wang and Y. Zhou, J. Phys.:condens. Mater., 2003, 15:5959-5968

15. X. Liu & M. Le Flem et al. – ICC2, 29 June -4 July 2008 Primary Research on Ion Irradiation of Ti 3 SiC 2 DMN/SRMA 10%Al 5%Al Obvious Color change for 10% Al at 500 0 C May be amorphous 500 0 C, Kr Thickness: 100 nm