Laboratoř neutronové fyziky. v rámci CANAM infrastruktury v ÚJF Řež 28/03/2014

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1 Pavel Strunz: Laboratoř neutronové fyziky v rámci CANAM infrastruktury v ÚJF Řež Přemysl Beran: Prášková neutronová difrakce: okno do hmoty Vasyl Ryukhtin: Využití maloúhového rozptylu neutronů pro materiálový výzkum v NPL Řež Pavel Strunz: Příspěvek neutronového rozptylu k vývoji nových materiálů 28/03/2014 Pavel Strunz, Workshop CE AdMat, FJFI ČVUT v Praze, Trojanova 13,

2 Laboratoř neutronové fyziky v rámci CANAM infrastruktury v ÚJF Řež 28/03/2014 Pavel Strunz, Workshop CE AdMat, FJFI ČVUT v Praze, Trojanova 13,

3 Center of Accelerators and Nuclear Analytical Methods (CANAM) Center of Accelerators and Nuclear Analytical Methods (CANAM infrastructure) offers to scientists and industry a unique experimental infrastructure in nuclear physics and neutron science. It comprises 3 major research laboratories of the Nuclear Physics Institute of the ASCR: Laboratory of Tandetron (LT) operating an accelerator Tandetron 4130 MC Neutron Physics Laboratory (NPL) providing facilities at LVR-15 the reactor Laboratory of Cyclotron and Fast Neutron Generators (LC & FNG) operating the isochronous cyclotron U-120 Experimental facilities of the CANAM infrastructure are opened to the users in Open Access mode. Nuclear Physics Institute of the ASCR public research institution ACADEMY OF SCIENCES OF THE CZECH REPUBLIC

4 Laboratory of Tandetron (LT) The Tandetron 4130 MC is a compact electrostatic tandem accelerator for production of ion beams with energies in the range 400 kev 24 MeV of almost all elements of the periodic system. LT offers ion implantation and a set of nuclear analytical methods: RBS (Rutherford Backscattering Spectrometry) - high sensitivity for heavy elements - low detection limit - about nm depth resolution in elemental depth profiling RBS channeling - channeling of charged particles in crystalline matrix - structural studies ERDA, TOF-ERDA - Elastic Recoil Detection Analysis - depth profil -ing of light elements in thin layers and in multilayer systems PIXE, PIGE - Particle Induced X- or γ-ray Spectroscopy - light elements analysis. - high sensitivity detection limit: up to 100 ppm (PIXE), 1000 pm (PIGE) The Tandetron accelerator and adjacent ion beam lines External beam - investigation of samples unstable under vacuum conditions or too large to be mounted in a vacuum chamber Ion Micro-beam - focusing of an ion beam on the dimension about 1 mm on the sample - a versatile equipment that allows 3D elemental mapping of microstructures

5 Neutron Physics Laboratory CANAM infrastructure Nuclear Physics Institute (NPI), Řež near Prague, Czech Republic NPL mission neutron-physics experiments according to the NPI research program providing the experimental facilities and research experience to external users in the open access mode Pavel Strunz, Workshop CE AdMat, FJFI ČVUT v Praze, Trojanova 13, /03/2014 5

6 Research reactor LVR15 in Rež neutron source Neutron Physics Laboratory 6

7 Neutron Physics Laboratory (NPL) Experimental basis horizontal and vertical neutron channels at the research reactor LVR-15 (Research Centre Řež), max. flux n/s/cm 2 Access: 8 facilities (3 nuclear-analytical techniques, 5 diffraction techniques) NPL: small lab compared to large neutron-physics centres => focus on the fields where unique facilities can be provided 28/03/2014 7

8 NPL: activation analysis and nuclear physics T-NDP NG NAA Neutron Depth Profiling: non-destructive analysis of concentration profiles of light elements (diffusion, sputtering, corrosion, electronics, optronics, life sciences) Thermal neutron facility for study of γ-γ coincidences from (n,γ) reactions: Prompt Gamma Activation Analysis; photon strength functions, nuclear structure Neutron Activation Analysis: low-level elemental characterization - biology, biomedicine, environment, geology, archaeometry 28/03/2014 8

9 NPL: neutron diffraction facilities TKSN-400 SPN-100 MAUD Neutron optics based on bent Si High-resolution diffractometer: microstrains in polycrystals, deformation mechanism, in-situ thermo-mechanical processing, phase transformations in alloys (steels, SMA, etc.) Diffractometer for macrostrain scanning of polycrystalline materials residual stresses (welds, materials after processing) Double crystal small-angle neutron scattering: microstructural studies (precipitation in alloys, porosity) NOD MEREDIT Neutron optics diffractometer for tests of neutron optics and imaging Medium resolution powder diffractometer: standard diffraction experiments; experiments with sophisticated sample environment (T, deformation) 28/03/2014 9

10 Neutron scattering: Structure, microstructure, excitations Properties of neutron thermal neutrons: energy about 25 mev ( J), corresponds to wavelength 1.8 Å (0.18 nm) and to velocity 2200 m/s (non-relativistic quantum particle; n-interferometry) cold neutrons: typically 1 mev, 9 Å and 437 m/s Structure, microstructure studies, like X-ray, but with different accent Why investigation of matter using neutrons? energies of excitations (phonons) in condensed matter similar to energy of neutron interatomic distances and sizes of nanostructures in condensed matter similar to wavelength of neutron March 28,

11 Interaction of X-ray and neutrons with atom X-rays Neutrons relative atomic weight March 28,

12 Properties of neutron magnetic moment non-monotonic dependence of scattering amplitude on atomic number no charge, weak interaction with matter Why investigation of matter using neutrons? study of magnetic structures and excitations positions of light (Li, H) and neighboring elements (Fe, Mn), contrast variation often very small absorption => large depths, volumes, in situ studies, non-destructive Typical sample thickness or penetration depth for various types of radiation electrons 1 mm X-ray 100 mm neutrons 5 mm March 28,

13 Disadvantage: Low flux (brightness) of sources excitations => Use neutrons when: magnetic structure and microstructure scattering contrast for X-ray too low or does not allow to resolve details (easier contrast variation for neutrons) sample: cannot be prepared in a thin form necessary for synchrotron without influencing the microstructure bulk information or non-destructive testing is needed absorption/scattering in sample-environment windows too high for X-ray (in-situ experiments) March 28,

14 In-situ studies at operational or processing conditions Low influence of the sample environment containing windows (cryomagnet, furnace, ): transparent for neutrons, negligible parasitic scattering Bulk investigated - Surface effects negligible (e.g. oxidation) Especially important for metallic materials: often treated or used at non-ambient conditions (e.g. high temperature) March 28,

15 Sample environment - NPL Close cycle cryostat Laybold model A901 ( K) Vacuum furnace radiation, vanadium heating elements, up to 1000 C Mirror furnace (up to 1000ºC), in innert gas, air or vacuum Transmission furnace for SANS (up to 1420ºC) deformation rig (up to ±20 kn), deformation rig (up to ±50 kn being installed March 2014) 28/03/ NMI3 15

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17 SPN Diffractometer for macrostrain scanning hkl d hkl d d 0, hkl 0, hkl Bragg law 2dsin =l d d hkl 0, hkl cot hkl hkl scattering from suitably oriented grains elastic strains only hkl ij Experimental quantity - strain tensor component strains can be converted to stresses using appropriate elastic moduli Engineer s aim - stress tensor ij

18 SPN Diffractometer for macrostrain scanning napětí (MPa) Application: Residual stress determination: around welds in metals after processing in ceramics (e.g. functionally graded Al 2 O 3 /Y-ZrO 2 ) in composites phase-specific stresses pracovní povrch x (mm)

19 Y /mm mstrain Neutron diffraction scanning of residual stresses and their effect on fatigue strength of high-strenght steels welds Ľuboš Mráz, Welding Research Institute Industrial Institute SR, Bratislava, Slovakia, Leif Karlsson, ESAB AB, Goetenburg, Sweden Deska J mstrain X mstrain Y mstrain Z Line of measurement mm weld m strain X deska J ,0 280,0-290,0-860, X / mm

20 Residual stresses of high-strenght steels welds - The effect of filler materials The effect of filler material Residual stress distribution in the vicinity of the WELDOX 700/690QL fillet test welds welded by various filler materials: A - LTT-M6, B - B-M3, C D4-6547, E - Tubrod 14.03, J - D3-5724

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22 Proposal of the Czech in-kind contribution for ESS- Scandinavia (Lund, Sweden) Coordinator: Nuclear Physics Institute ASCR, v.v.i. Co-proposer: Helmholtz-Zentrum Geesthacht, Germany Beamline for European materials Engineering Research (BEER) variable resolution ToF powder diffractometer 3D visualisation of Gleeble simulator with General purpose MCU surrounded by proposed neutron detectors Main features: In-situ thermo-mechanical testing and simulation of processing of engineering materials Combination of methods (diffraction, SANS, imaging) Support for user-supplied equipment and measurement of long-lasting processes

23 NPL experiments at large-scale facilities abroad Experiments at other large scale facilities for material science - succesfull proposal submissions (several each year) to Neutron laboratories abroad [PSI Villigen (CH), HZB Berlin, FRM-II Muenchen, ILL Grenoble ], but also synchrotron [ESRF Grenoble] 28/03/

24 Neutron physics laboratory (NPL), NPI Řež TKSN-400: High-resolution diffractometer: macro- and microstrains in polycrystals, in-situ thermo-mechanical processing, phase transformations in steels, SMA etc. LVR-15 MAUD: Double crystal small-angle neutron scattering: microstructural studies (precipitation in alloys, porosity in ceramics) NOD: Diffractometer for neutron optics tests PGAA open access canam.ujf.cas.cz MEREDIT: Medium resolution powder diffractometer: experiments with sophisticated sample environment (e.g. deformation +B) SPN-100: Diffractometer for macrostrain scanning of polycrystalline materials (welds) 28/03/