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Dubna material studies activity in the frame of IAEA and ISTC research projects

Dubna material studies activity in the frame of IAEA and ISTC research projects. Anatoly Balagurov Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research bala@nf.jinr.ru Dubna, Moscow reg. Danas Ridikas Physics Section, Division of Physical and Chemical Sciences

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Dubna material studies activity in the frame of IAEA and ISTC research projects

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  1. Dubna material studies activity in the frame of IAEA and ISTC research projects Anatoly BalagurovFrank Laboratory of Neutron Physics Joint Institute for Nuclear Research bala@nf.jinr.ru Dubna, Moscow reg. Danas RidikasPhysics Section, Division of Physical and Chemical Sciences D.Ridikas@iaea.org Department of Nuclear Applications and Science IAEA, Vienna • High-resolution neutron diffraction • Strain – Size effects in diffraction patterns • IAEA activity: Coordinated Research Projects • ISTC activity: Research Project • Collaboration with JINR Member States

  2. Neutron diffraction for material science Crystal structure: Magnetic structure: - crystal lattice - magnetic lattice - crystal symmetry - magnetic symmetry - atomic coordinates - magnetic moments values - thermal parameters - magnetic moments direction - occupancy factors Local structure: Microstructure: - local distortions - phase composition - local correlations - crystallographic texture - local disorder - macrostresses - size & strain effects - structural defects

  3. High-resolution diffraction for peak shift and broadening effects I. Macrostress → Peak shift = a/a = /E For min = 20 MPa and E ≈ 20·1010 Pa= 200 GPa (steel) we need in a/a ≈ 0.001 II. Peak broadening effects: Microstresses → a/a ≈ Const ≈ 0.001 Size effect → d/d = d/2πWx d ≈ 2 Å, Wx ≈ 300 Å, Δd/d ≈ 0.001 Very high resolution, R ≈ 0.001 or better, is needed!

  4. High-resolution neutron powder diffraction Continuous Sources: ILL, FRM-II, SINQ, … Short Pulse Sources: ISIS, SNS, J-SNS, … Long Pulse Sources: IBR-2, ESS, … W = 10 – 100 MW Δt0 = ∞ W = 2 – 5 MW Δt0≈ (300 – 1500) μs W = 0.1 – 1.2 MW Δt0≈ (15 – 30)∙λμs Long FP: L ≈ 100 m or fast chopper (Fermi / Fourier) λ = const diffractometer TOF diffractometer - λ ≈1.9Å - Monochromator take-off angle ≈ 120º - λ ≈0.5 - 4Å - Flight-pass ≥ 20 m Neutron pulse after fast chopper Δt0≈ (10 – 50) μs 4

  5. Resolution of TOF-diffractometer R(t, θ) = d/d = [(t0/t)2 + (θ/tgθ)2]1/2 t ~ L·sinθ,R  0ift0  0orL   andθ  0orθ  /2 TOF-diffractometer: d/d ≈ const ≈ 0.001 for d > 2 Å. HRFD, TOF, 20 m (IBR-2) HRPD, TOF, 100 m (ISIS)

  6. NAC standard (Na2Al2Ca3F14) on TOF and λ0 diffractometers HRFD (TOF): 2θ0=152, λ=1.2–7.2 Å HRPT (λ0):λ0=1.886 Å, 2θ=10-165 6

  7. Neutron spectrometers on the IBR-2M reactor Diffraction (6): HRFD, DN-2, SKAT, EPSILON, FSD, DN-6 SANS (2): YuMO,SANS-C Polarized neutron reflectometry (3): REMUR, REFLEX,GRAINS Inelastic scattering (2): NERA, DIN 13 spectrometers (3 new) 3 cold moderators (new) 7

  8. TOF diffractometers at the IBR-2M 1. HRFD – high resolution Fourier diffractometer crystal structure of powders, anisotropic broadening 2. DN-2 – multi-purpose diffractometer single crystals, magnetic structures, real-time studies 3. DN-12 (DN-6) – diffractometer for microsamples high pressure experiments 4. FSD – Fourier (RTOF) stress diffractometer internal stresses in bulk samples 5. EPSILON – TOF stress diffractometer internal stresses in bulk samples 6. SKAT – texture diffractometer texture of rocks and bulk samples

  9. Diffraction at the IBR-2M. Resolution. HRFD powders, stresses FSD stresses DN-2real-time, multilayers DN-6 high-pressure EPSILON stresses SCAT textures Resolution becomes better for longer d-spacing! 9

  10. HRFD – High Resolution Fourier Diffractometer at IBR-2 Put into regular operation in 1994 by collaboration: FLNP (Dubna), PNPI (Gatchina), VTT (Espoo), IzfP (Dresden). HRFD (Dubna): <2θ> = 152º t0= const 10 s L 21 m d/d ≈ const ≈ 0.001 for d > 2 Å 10

  11. Fast Fourier chopper at HRFD (Dubna) 0.7 mm Rotor Stator Dubna chopper: Al-alloy  = 50 cm N = 1024 <d> = 0.7 mm Vmax = 6000 rpm Ω = 100 kHz Δt0 = 10 μs Transmission = 0.25 Sbeam = 3x30 cm2 7.5 kW motor Triangular chopper transmission function: T(t) ~ 1 + sin ωt Binary pick-up signals for RTOF analyzer

  12. Rietveld analysis of the HRFD data (MRIA package) Diffraction pattern obtained withNAC-standard, Δd/d≈ 0.001

  13. HRFD: detectors around sample position

  14. “Size” and “strain” broadening of diffraction lines W2 = C1 + C2d2 + C3d2 + C4d4 Size of domains, C4~ (1/L)2 Microstresses, C3=(a/a)2 Resolution function of TOF-diffractometer Peak width for nanosizedNi with <D> ≈ 380 Å. W2(d 2)function for NAC and Al2O3 standard samples Microstresses in CaCuMn6O12 for two temperatures 14

  15. Applied researches at the IBR-2 steel Zr A part of the real VVER-1000 vessel(built-up welding stainless steel) Cross-section of the bimetallic steel-zirconium adapter Perforator’s striker Biaxially fatigued stainless steel sample of cruciform geometry

  16. IAEA project D2.01 Enhancement of research reactor (RR) utilization and applications List of major activities: • RR coalitions & networks • Research Reactor Data Base (RRDB) • Coordinated Research Projects • Technical (TM) and Consultancy (CM) Meetings • International RR Conference, Workshops, Schools • Support of national & regional TC projects • Publications, technical reports, brochures NEW ! More information available at: http://www-naweb.iaea.org/napc/physics/research_reactors 16

  17. New RRDB capability: utilization & applications oriented Available at: http://www-naweb.iaea.org/napc/physics/research_reactors/ or USB Memory Stick, <10MB, no internet is needed!

  18. New RRDB capability: utilization & applications oriented 44 RRs employ neutron beams; they are distributed over 30 MSs Available at: http://www-naweb.iaea.org/napc/physics/research_reactors/ or USB Memory Stick, <10MB, no internet is needed!

  19. IAEA activity: Coordinated Research Projects CRP 1314 (2006-2009):Development and application of the techniques of residual stress measurements in materials Objectives:  characterization, tests and development of materials  development of new instruments & upgrade of existing facilities  advanced analysis of material stresses – links to industrial partners  harmonisation and standardization procedures (e.g. round robin experiment)  5 Research Contracts + 4 Research Agreements • Czech Republic • Germany • Hungary • India • The Netherlands • Pakistan • Romania • Russian Federation • South Africa Main achievements/outlook:  Creation of network on residual stress  Transfer of know-how from RA holders to RC (developed  developing)  Round Robin experiments are ongoing (+USA, +Australia, +UK)  Project report for Technical Report Series is in preparation

  20. Application of Reverse Time of Flight (RTOF) Neutron Diffraction for Residual Stress Investigations The main tasks of the project were devoted to modernization of the main units of FSD diffractometer: 1) Installation of new detector modules; 2) Precise sample alignment system improvement; 3) Adaptation of the new mechanical testing machine for tensile/compressive test with force and temperature control. 90º-detectorsystembased on ZnS(Ag) scintillator with wavelength-shifting fibers

  21. FSD diffractometer Backscattering detector Status of the detector system: Six modules of ZnS(Ag) +90° (on the left) and -90° (on the right) detectors are currently installed on FSD. Two new modules are in preparation. 90º-detector Sample position Neutron guide

  22. IAEA activity: Coordinated Research Projects Active CRP 1575 (2009-2012): Development, Characterization and Testing of Materials of Relevance to Nuclear Energy Sector Using Neutron Beams (SANS, diffraction and neutron radiography) • Objectives: • investigation and characterization of materials relevant to nuclear energy applications • optimization and validation of experimental and modeling methods • creation of a database of reference data for nuclear materials research • enhancement of the capacity of research reactors for nuclear materials research •  8 Research Contracts + 9 Research Agreements • Argentina • Australia • Brazil • China • Czech Republic • France • Germany • Hungary • Indonesia • Italy • Japan • Korea • The Netherlands • Romania • Russian Federation • Switzerland • USA • Expected output: • Materials characterized, experimental/modelling methods optimized • Creation of multilateral network in the field of advanced nuclear materials research • Creation of an experimental reference database for models and calculations • Final project publication

  23. Ferrite-Martensite Steels Dispersion Hardening Studied by TOF Neutron Diffraction Scientific scope of the project: Relation between dispersion-hardening particle size and microstress value in steel. The influence of these parameters on strength characteristics of steels at various temperatures. Subject of studies: High-strength dual-phase ferrite - martensite steels (soft ferrite matrix containing islands of martensite) with dispersion-hardened phases: Fe-12%Cr matrix + V/Mo/Nb carbides (EP-450), V/W/Nb nitrides (EP-900), EP-450 ODS (oxide dispersion strengthened by Y2O3). Experimental technique: High-resolution TOF neutron diffraction with high-temperature in situ loading.

  24. Five main topics to be addressed: • Utilization & Applications of RRs • Operation & Maintenance • New RR Projects • Safety of RRs • Spent Fuel Management, Waste & Decommissioning • Jointly by NA, NE, NS and TC • Contact: D. Ridikas@iaea.org 24

  25. ISTC project № 3074.2 Neutron-Diffraction Study of Micro- and Macrostresses in Structural Ageing Alloys for Nuclear Power Engineering after Thermal and Radiation Exposure and Predicting Resistance to Radiation-Induced Swelling Participants: Institute of Metal Physics, Yekaterinburg Joint Institute of Nuclear Research, Dubna Institute of Technical Physics, Snezhinsk Period of realization: September, 2008 – February, 2011 (30 months) Budget: $253,229 Euro Foreign Experts: Dr. Rainer Schneider, Berlin Dr. Carsten Ohms, Petten Dr. Pavol Mikula, Prague

  26. ISTC project № 3074.2 First task: microstresses in the bulk of the components from radiation-resistant ageing alloys in the course of formation, growth and coagulation of the second-phase disperse particles. Steels with coherent Ni3Ti intermetallic precipitates, semi-coherent and incoherent VC carbides will be studied. Second task: analysis of microstresses around defect clusters formed in place of displacement cascades under neutron irradiation. Third task: investigation of residual macro- and microstresses arising as a result of phase and structural transformations in steel and alloys, predominantly in the thermally affected zone of weld seams of large-diameter pipes.

  27. Austenitic steel Fe0.748Mn0.179V0.013Cr0.042C0.018 with VC precipitates Three samples have been studied after quenching from 1100ºC: initial, annealed at 600оС and 700оС. Annealing time was 1, 6, and 12 hours. The lattice parameter dependence for 40Х4Г18Ф steel vs. annealing time at two temperatures: 600оС and 700оС. The strain (Δa/a) dependence for 40Х4Г18Ф steel vs. annealing time at two temperatures: 600оС and 700оС. Comparison of diffraction patterns for 40Х4Г18Ф steel samples: initial and aged at 600оС and 700оС in 12 hours.

  28. Investigation of the atomic and magnetic structures of crystals and internal stresses in bulk materials and components In the frame of JINR – NECSA project: “Neutron Scattering Applications” Co-ordinator from JINR: Dr. Anatoly M. Balagurov Co-ordinator from NECSA (South Africa): Dr. Anrew M. Venter 1. Instruments development 2. Joint experiments: “Stresses in biaxially fatigued stainless steel sample of cruciform geometry” “Residual stresses in a stainless steel-Ti(Nb) bimetallic tube adapter”

  29. Joint experiment in 2009/2010 “Residual stresses in biaxially fatigued stainless steel sample of cruciform geometry” SALSA (ILL, France) & POLDI (PSI, Switzerland Metastable austenitic stainless steel AISI 321 were subjected to the in-plane biaxial tension-compression fatigue cycling on the INSTRON planar biaxial loading machine at FIMS (Bremen). Residual stresses in to the ex-situ in-plane biaxial low cycle fatigued sample of the cruciform geometry from AISI 321 were measured at SALSA (ILL) and POLDI (PSI) instruments. Spectra from the martensite (left side) and austenite (right side) in the Krest-2 sample measured on the SALSA. (211) martensite Vg = 0.5 mm3 texp= 20 to 35 min. (220) austenite Biaxially fatigued stainless steel sample of cruciform geometry at POLDI (SINQ neutron source, PSI).

  30. Joint experiments in 2010/2011 “Residual stresses in a stainless steel-titanium/niobium bimetallic tube adapter” POLDI diffractometer at SINQ, PSI (Villigen, Switzerland) Stainless steel-titanium bimetallic tube adapters are being considered for use in superconducting radiofrequency cavities. Hermetic welding of the adapter is achieved by explosive bonding method. The residual stresses into the adapter are of large practical interest for the improvement of explosive welding technology and minimization of the production cost. A set of samples are prepared for investigation of residual stresses in bimetallic joining. Bimetallic tube is placed at the POLDI diffractometer, SINQ neutron source, PSI.

  31. User program at the IBR-2M spectrometers Time-sharing (13 spectrometers) FLNP (35%) International experts’ commissions: External fast (10%) I. Diffraction II. Inelastic Scattering III. Polarized neutrons IV. SANS External regular (55%) User statistics Others, 19% FLNP, 25% France, 3% Poland, 5% Germany, 17% Russia, 31%

  32. You are invited for experiments at the IBR-2M reactor in Dubna – a nice place at the Volga River

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