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3D X-Ray Diffraction Microscopy Larry Margulies. 200 µm Metal Structures Heat Defor- mation 200 µm 5 µm Challenges: - Multiple lengthscales - Heterogeneities.

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Presentation on theme: "3D X-Ray Diffraction Microscopy Larry Margulies. 200 µm Metal Structures Heat Defor- mation 200 µm 5 µm Challenges: - Multiple lengthscales - Heterogeneities."— Presentation transcript:

1 3D X-Ray Diffraction Microscopy Larry Margulies

2 200 µm Metal Structures Heat Defor- mation 200 µm 5 µm Challenges: - Multiple lengthscales - Heterogeneities - Predicting the dynamics 4D (space + time) Traditional Microscopy is 2D

3 3DXRD Vision 3D characterization of individual grains within bulk polycrystals –Volume –Crystallographic orientation (intragranular ODF) –Grain boundary morphology (3D mapping) –Elastic strain tensor –Structural refinement Statistics over 100-1000 structural units In-situ annealing and deformation studies(4D)

4 3DXRD set-up Area detector Detector I L = 5-10 mm Position and Orientation Detector II L = 40 cm Orientation and Strain Acq. time: 1-10 sec 10-100 msec

5 Two step process Up to 1000’s grains: CMS position volume: 1-10% average orientation: 0.2 deg average elastic strain:  =10 -4 1. Indexing: GRAINSPOTTER IMAGED11 2. Reconstruction GRAINSWEEPER

6 Growth curves Farfield detector only:Growth curves: 244 grains Statistics New Avrami-type model 0 1 2 log (time) log(-ln(1-V V ))

7 g a g a q a b      Pearlite – Ferrite – Austenite Growth curves dN/dt Phase Transformations in Carbon Steel N Activation energy off by 100!

8 Grain rotation for 95 grains in Al, 100  m grains, 5 mm thick Tensile strain: 6 % Grain rotation

9 Third route in Crystallography Single Crystal Powder X-ray data: Multicrystal

10 Third route in Crystallography Validation: Cu(C 2 O 2 H 3 ) 2. H 2 O. 70 grains of size < 1 micron Cell ~1400 Å 3 (C2/c) Result: Single crystal quality refinement! Applications to: Pharmacy Photochemistry Protein Crystallography

11 Grain Mapping Area detector Detector I L = 5-10 mm Position and Orientation Detector II L = 40 cm Orientation and Strain

12 Video of growth of an internal grain Recrystallization of 42% deformed pure Al during annealing at ~200 C.

13 Grain growth Sample: Al(0.1% Mg) Initial 800 min anneal at 450 C 491 grains 49 grains

14 Present detector Resolution: ~3µm Efficiency: ~1% Long tails in PSF Sample YAG:Ce 25µm YAG 150µm CCD

15 Structured Scintillator Principle:Electrochemical etch: @ KTH, Sweden

16 LuAG 25µm SS 4µm pitch Tomographic images of Al with W particles taken with a conventional LuAG 25µm thick screen and a structured scintillator with a 4µm pitch

17 3D high resolution detector –mapping of deformed microstructures –“box beam” mapping Faster throughput for in-situ mapping 100 nm resolution 2D(3D) detector –R&D is needed for a solid state device Future of 3DXRD faster and smaller

18 Acknowledgments Risø: H.F. Poulsen, C. Gundlach, D. Juul Jensen, E. Knudsen, E.M. Lauridsen,W. Pantleon, S. Schmidt, H.O. Sørensen, G. Winther ESRF, ID11: A. Goetz, Å. Kvick, G. Vaughan, J. Wright

19 3DXRD Instrumentation Optics (brown): WB: White beam LC: Bent Laue crystal WBS: White beam stop ML: Bent multi layer MB: 2 dimensionally micro focussed monochromatic beam BS: Monochromatic beam stop Sample environment (yellow): I: Cryostat II: Furnace III: 24kN Stress rig Detectors / slits (purple): 1: Large area detector 2: Conical slit system 3: High resolution area detector 4: Optional detector system 5: Small area detector


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