2010 ULTRASONIC BENCHMARKS

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1 World Federation of N D 2010 ULTRASONIC BENCHMARKS E Centers Problems for 2010 This year for the ultrasonic benchmark we have some extensive results of tests performed on a planar block containing surface breaking flaws of different heights and extensions. Side drilled holes (SDH) and flat bottom holes (FBH) were also present in the block for comparison. Data acquisition was performed with two immersion probes, both having a nominal 5 MHz central frequency but two different diameters. The experimental data for these studies have been obtained by the Commissariat a l énergie atomique (CEA) in France. We would like to thank the researchers at CEA for their extensive efforts in designing these benchmarks and for obtaining the responses.

2 Description of the configurations water Specimen and defects 1/3 H10% H10% H10% H10% H10% H30% FBH Tilt 45 φ2mm 5 mm thickness part of the specimen 5mm 20mm H10% H30% SDH φ2mm Depth 5 mm SDH φ2mm Depth 15 mm 20 mm thickness part of the specimen water FBH Tilt 60 φ2mm Extension : E (width 0.3mm) height : H (H = 10%, 30% or 50% of the specimen thickness (which is 5 mm or 20 mm)

3 Description of the configurations 5 mm thickness part of the specimen 40mm 79mm 20 mm thickness part of the specimen 177mm Specimen and defects 2/3 15 mm 15 mm 80mm φ2mm Tilt 45 40mm 20 mm 20 mm 20 mm 20 mm 40mm 280 mm 40mm 95mm 90mm 40mm 40mm 40mm 105mm 40mm φ2mm Tilt 60 Flaw s extension : 2, 5, 15 mm Flaw s extension : 2, 5, 15 mm

4 Description of the configurations Specimen and defects 3/3 30 defects : 26 flaws, 2 SDH and 2 FBH 20 mm thickness part of the specimen : - 2 side drilled holes, diameter 2 mm, extension 40 mm, the center of the SDH are positionned at 5 and 15 mm depth - 2 flat bottomed hole oriented at 45 and 60, diameter 3 mm, the center of the FBH are positionned at 10 mm depth - 2 rectangular defects of extension 2 mm and height 2 mm, one backwall breaking defect and one surface breaking defect - 2 rectangular defects of extension 5 mm and height 2 mm, one backwall breaking defect and one surface breaking defect - 2 rectangular defects of extension 15 mm and height 2 mm, one backwall breaking defect and one surface breaking defect - 2 rectangular defects of extension 15 mm and height 6 mm, one backwall breaking defect and one surface breaking defect 5 mm thickness part of the specimen : - 6 rectangular defects of 2 mm extension: - 2 with a height of 0.5 mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 1.5 mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 2.5 mm : one backwall breaking defect and one surface breaking defect - 6 rectangular defects of 2 mm extension: - 2 with a height of 0.5 mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 1.5 mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 2.5 mm : one backwall breaking defect and one surface breaking defect - 6 rectangular defects of 2 mm extension: - 2 with a height of 0.5mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 1.5 mm : one backwall breaking defect and one surface breaking defect - 2 with a height of 2.5 mm : one backwall breaking defect and one surface breaking defect Specimen: Ferritic steel Density: 7.8 g cm -3 c L : 5900 m. s -1 c T : 3230 m. s -1

5 Description of the configurations Probe s parameters 1/5 L0 110mm Incidence angle Scanning repositioning Water path Probe Φ 12.7 mm Used for the 20 mm thickness part of the specimen Probe Φ 6.35 mm Used for the 5 mm thickness part of the specimen T (Transverse) 45, immersion Planar circular probe Diameter of the circular crystal: 12.7 mm Nominal Center frequency: 5 MHz Incidence angle I: Water path for T45 = 20 mm T (Transverse) 45, immersion Planar circular probe Diameter of the circular crystal: 6.35 mm Nominal Center frequency: 5 MHz Incidence angle = Water path for T45 = 10 mm

6 Probe s characterization on a point like target Probe Φ 12.7 mm Probe s parameters 2/5 Probe displacement in the XY plane Y 11 mm Probe Probe displacement in the XZ plane Z 11 mm Echodynamic curve, plan XZ Direction X, 110 mm increment Y Z X scanning Balayage Position at the beginning of the displacement: 175 mm. Displacement of the probe in the (X, Y) and (X, Z) planes Echodynamic curve, plan XY Point like defect Position of the maximum amplitude = 115 mm ( mm) 110 mm Position at the beginning of the displacement: 175 mm from the probe Position at the end of the displacement: 105 mm from the probe

7 Probe s characterization on a point like target Probe Φ 12.7 mm Probe s parameters 3/5 10 mm Echodynamic curve Probe 10 mm L(-6dB) = 4.9 mm Y Y X Z Displacement of the probe in the (Y,Z) plane at a distance of 115 mm from the point like target (focal length) 6 db Point like target A-scan F-scan 6 db 2.6 MHz L(-6dB) = 5.2 mm Echodynamic curve 3 µs 4 MHz MHz

8 Probe s characterization on a point like target Probe Φ 6.35 mm Probe s parameters 4/5 Probe displacement in the XY plane Y 2 mm Probe Probe displacement in the XZ plane Z 2 mm Echodynamic curve, plan XZ Echodynamic curve, plan XY Direction X, 60 mm increment Y Z X scanning Balayage Position at the beginning of the displacement: 70 mm. Displacement of the probe in the (X, Y) and (X, Z) planes Point like defect Position of the maximum amplitude = 30 mm (70-40 mm) Direction X, 60 mm Position at the beginning of the displacement: 70mm from the probe Position at the end of the displacement: 10mm from the probe

9 Probe s characterization on a point like target Probe Φ 6.35 mm Probe s parameters 5/5 4 mm Echodynamic curve Probe 4 mm L(-6dB) =2.1 mm Y Y X Z Displacement of the probe in the (Y,Z) plane at a distance of 30 mm from the point like target (focal length) 6 db Point like target A-scan F-scan 6 db 2.8 MHz L(-6dB) = 1.9 mm Echodynamic curve 1.5 µs 4.3 MHz MHz

10 Probe s characterization (SDH) The T wave refracted angle obtained in the specimen for the applied incidence angle (18.94 ) for both probes was checked by measuring the T direct echoes of side drilled holes (SDH) positioned at different depths in a calibration specimen. An example of a experimental Bscan is presented below. scanning Side drilled holes - Φ 2 mm - depth from 4 mm to 60 mm, step 4 mm - space between 2 SDH: 15 mm B-scan T direct echoes Echodynamic curve

11 Description of the configurations displacement Each probe was moved in two perpendicular directions over each defect. The wave forms received at each position of the probe have been stored (experimental Cscans) The maximum amplitude of the rectified echo was also recorded for each defect The path and name of the main T echoes of the planar flaws are: Half skip echo or corner echo (backwall breaking flaw) Full skip echo (surface breaking flaw)

12 Description of the data Probe Φ 12.7 mm Probe Φ 12.7 mm Experimental results Bscan over the 2 SDH and the FBH Reconstructed B-scan SDH 5 mm depth T direct echo SDH 15 mm depth T direct echo T direct echo FBH T indirect echo T corner echo A table is given (see later) of the amplitude in db of the T direct echoes of the SDH at the depth of 15 mm and of the FBH at the depth of 10 mm relative to the amplitude of the T direct echoes of the SDH at the depth of 5 mm

13 Description of the data Probe Φ 12.7 mm Experimental results Example of a Bscan over a surface breaking and a backwall breaking flaws 20mm B-scan A table is given (see later) of the amplitude in db - - of the T-wave half skip (corner) echoes of the backwall breaking flaw - of the full skip echo of the surface breaking flaw relative to the amplitude of the T-wave direct echoes of the SDH at the depth of 5 mm and that for the all the planar flaws of the 20 mm part of the specimen Echos obtained from the surface breaking flaw when the probe is moved just over it Surface breaking flaw Full skip echo Backwall breaking flaw Half skip (corner) echo

14 Description of the data Probe Φ 6.35 mm Experimental results Example of a B-scan over 3 surface breaking and 3 backwall breaking flaws A table is given (see later) of the amplitude in db - - of the T-wave half skip (corner) echoes of the backwall breaking flaw - of the full skip echoes of the surface breaking flaw relative to the amplitude of the T-wave direct echoes of the SDH at the depth of 5 mm and that for the all the planar flaws of the 5 mm part of the specimen Bscan Backwall breaking flaw Half skip (corner) echo Echos obtained from the surface breaking flaw when the probe is moved just over it Surface breaking flaw Full skip echo

15 Data Probe Φ 12.7 mm Table 1 Experimental results obtained with the probe Φ 12.7 mm 20 mm thickness part of the specimen Relative amplitudes (db) - of the T-wave half skip echo of the backwall breaking flaws -of the T-wave full skip echo of the surface breaking flaws - of the SDH and FBH Flaws Height Extension Relative amplitude (db) surface breaking 0,1 2 mm 1,2 backwall breaking 0,1 2 mm 2,5 surface breaking 0,1 5 mm 7,5 backwall breaking 0,1 5 mm 9,4 surface breaking 0,1 15 mm 11,2 backwall breaking 0,1 15 mm 13,4 surface breaking 0,3 15 mm 16,8 backwall breaking 0,3 15 mm 19,2 SDH 5mm depth φ 2mm 40 mm 0,0 (reference) SDH 15mm depth φ 2mm 40 mm 0,4 FBH 45 10mm depth φ 3mm - 3,0 The amplitude of reference A ref = amplitude maximum of the echo of the SDH of diameter 2 mm at 5 mm depth The relative amplitude A R printed in the table is in db: 20 log(a / A REF ) - ( G - G REF ) Where G and G REF are the gains in db.

16 Data Probe Φ 12.7 mm Same results as those presented in the previous slide for the surface and backwall breaking flaws T45 Surface breaking flaw Backw all breaking flaw Amplitude (db). ref amp SDH 5 mm depth, T Flaw's number Flaw n 1 : extension 2mm xheight 2mm Flaw n 2 : extension 5mm x height 2mm Flaw n 3 : extension 15mm x height 2mm Flaw n 4 : extension 15mm x height 6mm

17 Data Probe Φ 6.35 mm Table 2 Experimental results obtainded with the probe Φ 6.35 mm 5 mm thickness part of the specimen Relative amplitudes (db) - of the T-wave half skip echo of the backwall breaking flaws -of the T-wave full skip echo of the surface breaking flaws - of the SDH Flaws Heigth Extension Relative amplitude (db) surface breaking 10% 2 mm -5,9 backwall breaking 10% 2 mm -5,4 surface breaking 30% 2 mm 1,1 backwall breaking 30% 2 mm 2,0 surface breaking 50% 2 mm 3,0 backwall breaking 50% 2 mm 4,3 surface breaking 10% 5 mm -1,9 backwall breaking 10% 5 mm -0,2 surface breaking 30% 5 mm 5,6 backwall breaking 30% 5 mm 7,5 surface breaking 50% 5 mm 7,6 backwall breaking 50% 5 mm 9,6 surface breaking 10% 15 mm -1,6 backwall breaking 10% 15 mm 0,4 surface breaking 30% 15 mm 6,1 backwall breaking 30% 15 mm 7,9 surface breaking 50% 15 mm 8,0 backwall breaking 50% 15 mm 10,0 SDH 5mm depth φ 2mm 40 mm 0.0 (reference) SDH 15mm depth φ 2mm 40 mm -2,9 The amplitude of reference A ref = amplitude maximum of the echo of the SDH of diameter 2 mm at 5 mm depth The relative amplitude A R printed in the table is in db: 20 log(a / A REF ) - ( G - G REF ) Where G and G REF are the gains in db.

18 Data Probe Φ 6.35 mm Same results as those presented in the previous slide for the surface and backwall breaking flaws T45 Amplitude (db), ref: SDH 5 mm depth T45 direct echo mm ext 0.5, 1.5 and 2.5 mm height 5 mm ext 0.5, 1.5 and 2.5 mm height N of the flaw 15 mm ext 0.5, 1.5 and 2.5 mm height Surface breaking flaw, 2 mm extension Surface breaking flaw, 5 mm extension Surface breaking flaw, 15 mm extension Backwall breaking flaw, 2 mm extension Backwall breaking flaw, 5 mm extension Backwall breaking flaw, 15 mm extension

19 Data, 5 mm depth Side Drilled Hole (reference), T-wave direct echo A-scan F-scan of the specular echo Probe Φ 12.7 mm Creeping wave 3.8 MHz Specular echo 4 µs Probe Φ 6.35 mm 4.4 MHz MHz 3.1 MHz Creeping wave Specular echo 3 µs 4.5 MHz MHz

20 PARTICIPATION IN THE STUDY We ask that you compare your model results to the experimental values given in Tables 1 and 2 plus any other comparisons you may like to perform with the other results given. Results of these benchmark studies will be presented at the 37th Annual Review of Progress in Quantitative Nondestructive Evaluation (RPQNDE) meeting, which will be held July 18-23, 2010 at the Marriott San Diego Mission Valley, California. We plan to hold a benchmark session at that meeting for these and other problems. To present your benchmark results at that session, please note that the deadline for submitting an abstract is May 7, 2010 (mark on your abstract that it is for the benchmark session). However, feel free to work on these problems even if you are not presenting at that meeting. Also, the advance registration deadline for the conference is June 14, For more details of the RPQNDE conference, visit the website at For any questions, please Prof. Schmerr at lschmerr@cnde.iastate.edu. Les Schmerr Permanent Secretary, World Federation of NDE Centers April, 2010