Towards near real- time data analysis and instrument calibration - PowerPoint PPT Presentation

Towards near real- time data analysis and instrument calibration at the Necsa Neutron Strain Scanner D. Marais and A.M. Venter Radiation Science, Research and Development Division, The South African Nuclear Energy Corporation (Necsa) SOC Limited

Who we are and what we do • South African Fundamental Atomic Research Installation – A.k.a. SAFARI-1 Research Reactor – 20MW Tank-in-pool – Commissioned in 1965 – Flux 4x10 14 n.cm -2 .s -1 – Medical isotopes – Irradiation services – Neutron activation analysis – Neutron beam line facilities 2

Neutron Diffraction Facility (NDIFF) MPISI PITSI Materials Probe for Internal Powder Instrument for Transition Strain Investigations in Structure Investigations Spotted hyena in Zulu Zebra in Sotho 3

Neutron strain scanning Alignment Monochromator Centre of rotation Beam apertures → Q ∆d Sample 1.178 1.182 1.178 1.1775 1.18 1.177 1.178 1.177 1.176 1.176 1.1765 1.175 1.174 1.176 -60 -60 -48 -48 -36 -36 -60 -44 -28 -12 4 -24 -24 -12 -12 0 0 12 12 24 24 2.1 2.1 2.1 20 36 52 36 36 48 48 60 60 4

MPISI DAC Primary & Secondary Shutters Monochromator – Si (331) • 6 Stages – Rotate, Tilt, X, Y, Z, horizontal focus Android remote • λ = 1.67 Å at 2 θ _M = 83.5° OpenInspire control Motion control cabinet Camera Server Galil DMC2280 motor Incident beam aperture • controllers 3 Stages – X, Y, Rotate • Hor: 0.3 – 5 mm, Ver: 0 – 20 mm Diffracted beam aperture • 2 Stages – X, Y • Ver: 0 – 20 mm GumTree Sample Table (Huber) Gui • 5 Stages – X, Y, Z, Sample Scanman Rotate, Detector Rotate • 250 kg and 250 mm travel Denex neutron ANSTO Histogram Beam monitor detector Server Eularian Cradle 3 Stages – Omega, Phi, Chi Newport ¼ cradle 2 Stages – Phi, Chi 5

Sample table Centre of Rotation • High definition camera – 1392(h) x 1040(v) 6.45µm square pixels – Telecentric lens with distortion < 3µm • Focused sy translated som softzero sy returned Align camera axes with set sample table axes OI Cam graphic – Adjust focus for scaling factor sy -1.499756 3.50 3.50 -1.499512 som 0.0 0.0 2.044 2.044 Edge positions 589.95, 871.28 647.82, 863.66 626.74, 842.16 596.55, 877.61 Centre 730.61 755.74 734.45 737.08 • COR offset Rotation 0 45 90 All (aligned) calculation OI Cam graphic methods – 3 Positions Edge positions 922.37, 1171.96 655.57, 880.58 272.92, 501.25 463.03, 729.16 – 4 Positions Pin width (px) 249.59 225.01 228.33 266.13 Centre 1047.165 768.075 387.085 596.095 Corrected edges 891.48, 1202.85 612.39, 923.76 231.40, 542.77 440.41, 751.78 6

Data acquisition strategies Time based 0.03 Statistics based Intensity / time [n/s] 0.025 y = 0.0043x + 0.0002 0.02 0.015 0.01 User specifies User specifies 0.005 Aluminium • • Fixed measurement time Max measurement time 0 0 1 2 3 4 5 6 • • Fixed sample positions Peak fit criteria Gauge volume [mm 3 ] • Fixed sample positions 0.035 Peak / Background / Time [s -1 ] 0.03 Moves to next 0.025 y = 0.0063x - 0.0075 fixed position 0.02 Moves to next 0.015 fixed position 0.01 Data 0.005 0 acquisition Data 0 1 2 3 4 5 6 Gauge volume [mm 3 ] acquisition Time 0.3 reached Peak No Intensity / time [n/s] 0.25 ? y = 0.0045x + 0.0016 fitting 0.2 Yes 0.15 No 0.1 Max Fit More 0.05 time criteria Titanium 0 positions 0 10 20 30 40 50 60 reached reached No Yes ? Gauge volume [mm 3 ] ? ? No 0.03 Yes Yes 0.025 Intensity / time [n/s] Peak 0.02 More fitting 0.015 positions y = 0.0068ln(x) + 0.0005 0.01 Yes ? 0.005 0 No Data 0 10 20 30 40 50 60 analysis Gauge volume [mm 3 ] Data analysis 7

Statistics based DAQ implementation Histmem Source Fit Beam monitor Export ANSTO Histogram Server 8

Test case – Welded Iron sample -60 0 60 14.52 11.41 8.31 5.20 2.10 Weld collar Welded iron sample Secondary aperture Gauge volume Primary aperture 3x3x3 Const time Min Stdev: Stdev: intensity 4e-5 1.5e-5 Max time 600 600 1200 1800 Min intensity to background N/A 3 3 3 Min intensity N/A 100 10 10 Min % certainty intensity N/A 95 95 95 Min % certainty position N/A 99.993 99.993 99.9987 Corresponding stdev d-value N/A 4.00E-05 4.00E-05 1.50E-05 9

Results Const time Min intensity Stdev 4e-5 Stdev 1.5e-5 d-value d-value d-value d-value 1.1801 801 801 801 1.1799 799 799 799 2.10 2.10 1.1797 797 797 797 d-val 5.20 5.20 1.1795 795 795 795 8.31 8.31 1.1793 793 793 793 11.41 11.41 1.1791 791 791 791 14.52 14.52 1.1789 789 789 789 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 StDev d-value StDev d-value StDev d-value StDev d-value 1.00E-04 04 04 04 8.00E-05 05 05 05 2.10 2.10 Stdev d-val 5.20 6.00E-05 5 0E-05 05 5.20 8.31 8.31 4.00E-05 05 05 05 11.41 11.41 2.00E-05 05 05 05 14.52 14.52 0.00E+00 00 00 +00 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 2500 140 100 1400 120 1200 2000 80 Intensity 2.10 2.10 100 1000 1500 60 5.20 5.20 80 800 8.31 60 600 8.31 1000 40 40 400 11.41 11.41 500 20 20 200 14.52 14.52 0 0 0 0 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 700 700 1400 2000 600 600 1200 2.10 2.10 1500 500 500 1000 Time 5.20 5.20 400 400 800 1000 8.31 8.31 300 300 600 11.41 200 200 400 11.41 500 100 100 200 14.52 14.52 0 0 0 0 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 10

Comparison Stdev d-val Intensity Time stdev of d-values at 2.10 Intensity at 2.10 Time at 2.10 7.00E-05 2500 700 Time (h) 6.00E-05 600 2000 5.00E-05 500 Const time C 5.17 2.10 1500 4.00E-05 400 Min intensity 0.36 Mi 3.00E-05 300 1000 2.00E-05 200 stdev 4e-5 0.15 s 500 1.00E-05 100 stdev 1.5e-5 1.41 s 0.00E+00 0 0 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 stdev of d-values at 8.31 Time at 8.31 7.00E-05 1000 2000 Time (h) 6.00E-05 800 1500 5.00E-05 Const time C 5.17 600 4.00E-05 8.31 1000 Min intensity 2.09 Mi 3.00E-05 400 2.00E-05 500 stdev 4e-5 0.85 s 200 1.00E-05 stdev 1.5e-5 9.75 0 s 0.00E+00 0 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 stdev of d-values at 14.52 Intensity at 14.52 Time at 14.52 1.00E-04 350 2000 Time (h) 300 8.00E-05 1500 250 Const time C 5.17 14.52 6.00E-05 200 1000 Min intensity Mi 5.18 150 4.00E-05 stdev 4e-5 5.71 100 s 500 2.00E-05 50 stdev 1.5e-5 15.51 s 0.00E+00 0 0 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60 11

Conclusions and future projects • Automated, ‘ loggable ’ COR alignment achieved • Statistics based DAQ can save time, but is not a black box solution • Intelligent DAQ protocol – Initial measurement on course mesh – Identify regions with high stress gradients – Re-measure these areas with finer mesh – Automate the process 12

Acknowledgements • Vladimir Luzin for the entry curve software ‘ Alihn ’ • Rainer Schneider and Stefan Flemming for OpenInspire and telecentrical camera idea • ANSTO/PSI for the use of SICS and Gumtree • National Research Foundation of South Africa • Necsa SOC Limited • Nobugs for bringing the people together! 13

Questions 14