Nb3Sn Image Gallery

Schematic and Powerpoint

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Animated Powerpoint slide showing a deep metallographic zoom into an ITER CS conductor pptx (silent) - 3MB
pptx(not silent) - 5.3MB
Animated Powerpoint slide showing a deep metallographic zoom into an ITER CS conductor after testing in the high field zone of the SULTAN testing facility. Images by Charlie Sanabria. SULTAN-tested cable was provided by courtesy of Pierluigi Bruzzone (Plasma Physics Research Center) with agreement from Fusion for Energy. The CSJA2 cable was also provided by arrangement with the Japan Atomic Energy Agency (JAEA), Superconductor Technology Group, Division of Fusion Energy Technology. This is a considerably extended version of a slide originally presented as part of talk 3OrBB-07 by Peter J. Lee at MT-23, Wednesday, July 17, 2013.
Animated Powerpoint slide showing the components of an ITER TF conductor pptx - 876KB Animated Powerpoint slide showing the components of an ITER TF conductor. Images by Charlie Sanabria. SULTAN-tested cable was provided by courtesy of Pierluigi Bruzzone (Plasma Physics Research Center). Originally presented as part of talk "Understanding the Performance Degradation of CICC Conductors for ITER Under Testing in the SULTAN Facility" presented April 19th 2013 at NHMFL and 3OrBB-07 at MT-23, Wednesday, July 17, 2013 by Peter J. Lee.
ITER Fusion CICC conductor Nb3Sn Toroidal field TF JPG - 1.3MB ITER CS conductor after partial removal of the stainless steel jcket to reveal in the internal components. Images by Charlie Sanabria. SULTAN-tested cable was provided by courtesy of Pierluigi Bruzzone (Plasma Physics Research Center) with agreement from Fusion for Energy.

Creative Commons License
Image by Charlie Sanabria is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at https://nationalmaglab.org/.

ITER Fusion CICC conductor Nb3Sn Toroidal field TF JPG - 1.7MB ITER TF conductor after partial removal of the stainless steel jcket to reveal in the internal components. Images by Charlie Sanabria. SULTAN-tested cable was provided by courtesy of Pierluigi Bruzzone (Plasma Physics Research Center) with agreement from Fusion for Energy.

Creative Commons License
Image by Charlie Sanabria is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at https://nationalmaglab.org/.

SSC prototype strand cross-section 1024x909 382KB - JPG 2008 CICC Montage showing the components of a Superconducting Cable-In-Conduit Conductor for ITER.
Also available as:
2.4 MB Powerpoint
374 kB Transparent GIF (1024w x 909h)
1.4 MB Transparent PNG (1024w x 909h)
Higher resolution versions are available.
Older montage showing the components of a Superconducting Cable-In-Conduit 1198x898 324KB - JPG Older montage showing the components of a Superconducting Cable-In-Conduit for ITER Model Coil Program (1996).
IGC-AS (now Luvata) strand shown. This older version still shows up in presentations and publications and is kept here for archival puroposes.
Schematic diagram illustrating the four major designs of commercial Nb3Sn strand 904x1033 89KB -GIF Schematic diagram illustrating the four major designs of commercial Nb3Sn strand. Higher resolution versions available.
A15 Structure of Nb3Sn 616x584 171KB -PNG Nb3Sn forms a crystalline intermetallic compound with an A15 structure consisting of a BCC sub-lattice of Sn atoms and a pair of Nb atoms on each face.

Creative Commons License
A15 Structure of Nb3Sn by Charlie Sanabria is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at https://nationalmaglab.org/.

2D Images 

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A fracture cross-section of a partially reacted Nb3Sn filament 588x831 132KB - JPG A fracture cross-section of a partially reacted Nb3Sn filament (TWC MJR strand). MJR (modified jelly-roll) is a type of internal-Sn strand that is no longer manufactured.
Golden Ears of Nb3Sn Corn II 424x608 128KB - JPG Golden Ears of Nb3Sn Corn II (IGC-AS Internal Sn ITER strand). Occasionally the fracture-cross-section process pulls out a filament and exposes the surface facets of the outermost Nb3Sn grains.† [False-color]
False color fractograph of SMI PIT Nb3Sn A15 layer 1231x829 941KB - JPG
1024x692 327KB - JPG
False color fractograph of SMI PIT Nb3Sn A15 layer. FESEM image colored for effect (a rejected image for the annual ASC Holiday/New Year card). Unreacted strand supplied to the UW by Shapemetal Innovation B. V., Enschede, The Netherlands.
False color image of filaments in polished cross-section of Furukawa ITER Nb3Sn strand 2462x1817 1.7MB - JPG
1024x756 129KB - JPG
False color image of filaments in polished cross-section of Furukawa ITER Nb3Sn strand. Note the exceptional uniformity and the barely discernable extra spacing between the original bundles of 19 filaments.
Another false color variant on the Furukawa ITER strand 2462x1817 3.4MB - JPG
1024x756 339KB - JPG
Another false color variant on the Furukawa ITER strand. The unreacted Nb cores (green) are more visible here. FESEM image.
False color images of Nb3Sn filament extracted for IGC-AS ITER strand 616x480 171KB - JPG
616x480 64KB - JPG
False color images of Nb3Sn filament extracted for IGC-AS ITER strand. FESEM image. The filament as approximately 1/25 the thickness of a sheet of paper.
Montage showing design of IGC-AS high Jc 1447x768 698KB - JPG
1024x544 176KB - JPG
Montage showing design of IGC-AS high Jc (critical current density) internal Sn strand. Heat treated strand supplied to the UW by IGC-Advanced Superconductors, Waterbury, CT.
Deep etch of IGC-AS internal Sn strand (Cu removed by etch). 1515x1447 849KMB - JPG
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Deep etch of IGC-AS internal Sn strand (Cu removed by etch).
False color FESEM image of deep-etch IGC-AS Nb3Sn strand. 1536x874 773KB - JPG
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False color FESEM image of deep-etch IGC-AS Nb3Sn strand.
A windows background image showing Nb3Sn filaments exposed by deep Cu etch. 980x720 78KB - JPG
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A windows background image showing Nb3Sn filaments exposed by deep Cu etch.
False color image showing filaments in unreacted MJR sub-element 1828x1806 119KB - GIF
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False color image showing filaments in unreacted MJR sub-element: TWC MJR Nb3Sn.
Etch cross-section of LMI Nb3Sn strand 1229x905 523KB - JPG
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Etch cross-section of LMI Nb3Sn strand for ITER showing partially reacted filaments with columnar interior A15 grains. FESEM.
False color image of fully reacted filament from LMI-ITER Nb3Sn strand 642x391 523KB - JPG
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False color image of fully reacted filament from LMI-ITER Nb3Sn strand.
LMI strand for ITER 2179x1582 1.3MB - JPG
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LMI strand for ITER. Etched partial cross-section showing three filaments adjacent to the diffusion barrier. FESEM.
Light microscope image of LMI Nb3Sn prototype strand 1260x960 1.3MB - JPG
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Light microscope image of LMI Nb3Sn prototype strand for ITER showing sub-elements of Nb3Sn filaments surrounded by diffusion barriers.
A really big FESEM fractograph of a Mitsubishi prototype 2462x1854 1.6MB - JPG
1020x768 254KB - JPG
A really big FESEM fractograph of a Mitsubishi prototype Nb3Sn strand for ITER. The filaments from this composite were particularly uniform and the properties were the best of the ITER developmental program.
A polished transverse cross-section of a Mitsubishi ITER Nb3Sn strand 925x953 540KB - JPG
748x768 86KB - JPG
A polished transverse cross-section of a Mitsubishi ITER Nb3Sn strand has been imaged by FESEM and then analyzed for filament size, uniformity and distribution (which in this case is particularly good). The analyzed filaments are highlighted in green.
False color fractograph of OI-ST high critical current density MJR Nb3Sn A15 layer. 1536x460 428KB - JPG
1024x520 161KB - JPG
False color fractograph of OI-ST high critical current density MJR Nb3Sn A15 layer. The strand has been ramped to final heat treatment temperature but has received its final HT. The Cu (red) and A15 (gold) colors have been added to help distinguish the components. FESEM. Unreacted strand supplied to the UW by Oxford Instruments Inc. - Superconducting Technology, Carteret, NJ.
False color electron backscatter 1024x810 167KB - JPG
1024x520 161KB - JPG
False color electron backscatter image of bulk Nb3Sn produced by HIP'ing powders at the UW-Madison. This is a two phase region with unreacted Nb in purple and Nb3Sn in green. FESEM.
False color image of VAC bronze process Nb3Sn filament after partial reaction. 1384x1080 838KB - JPG
984x768 224KB - JPG
False color image of VAC bronze process Nb3Sn filament after partial reaction. This highly distorted filament is unrepresentative of the otherwise excellent composite but of course it looks more interesting. FESEM. Strand courtesy of Vacuumschmelze GMBH, Hanau, Germany.
Transverse cross-section of VAC bronze-process 1024x699 411KB - JPG
1024x699 245KB - JPG
Transverse cross-section of VAC bronze-process Nb3Sn strand superimposed on detail showing filaments of Nb3Sn in sub-element groupings. FESEM. Strand courtesy of Vacuumschmelze GMBH, Hanau, Germany
False color image of Nb3Sn filaments in a IGC-AS strand exposed by a deep Cu etch. 2048x1536 1.5MB - JPG
984x768 225KB - JPG
False color image of Nb3Sn filaments in a IGC-AS strand exposed by a deep Cu etch.
Superconductor Rope Trick 1536x460 428KB - JPG Superconductor Rope Trick. For high magnetic field use, multifilamentary strands must be twisted so that eddy current losses, and flux jump and self-field instabilities are minimized. This produces the twisted rope appearance when viewed in longitudinal cross-section (FESEM-Electron Backscatter Image) of this Nb3Sn strand manufactured by IGC-AS (now Outokumpu Advanced Superconductors).
Strand used to produce record high field 1024x1280 689KB - JPG Strand used to produce record high field (16.1 T, 4.2 K). accelerator dipole magnet at LBNL. The strand has been fractured and imaged using an in-lens secondary electron detector in a FESEM in order to reveal grain size. The red and green channels have been processed by "Difference of Gaussians" and "Local Equalization" under Fovea Pro in order to enhance grain boundary contrast. The petal-like pattern originates from the original Nb filaments that were fused together during the reaction to for Nb3Sn. Strand manufactured by OI-ST and heat treated by Dan Dietderich and Ron Scanlan at LBNL.

3D Images

These image are vieweable in 3D using traditional red-blue glasses (typical of glasses used for 1950s horror movies).

The yellow/blue glasses provide better 3D viewing of color images and are provided free at the Applied Superconductivity Center during the annual Open House. You may also have these cardboard glasses from advertising promotions.

Thumbnail View Image Link Description
3-D Nb3Sn filament 480x613 289KB - JPG 3-D Nb3Sn filament! (IGC-AS Internal Sn ITER strand). Occasionally the fracture-cross-section process pulls out a filament and exposes the surface facets of the outermost Nb3Sn grains(3-D anaglyph image)
3-d (red-blue anaglyph)fractograph of IGC-AS high Jc 2137x3086 4MB - JPG
532x768 164KB - JPG
3-d (red-blue anaglyph)fractograph of IGC-AS high Jc (critical current density) strand cross-section. FESEM. Heat treated strand supplied to the UW by IGC-Advanced Superconductors, Waterbury, CT.
3-d (red-blue anaglyph)fractograph: IGC-AS ITER strand - extracted filaments. 1381x1972 1.2MB - JPG
538x768 73KB - JPG
3-d (red-blue anaglyph)fractograph: IGC-AS ITER strand - extracted filaments.
3-d (red-blue anaglyph)fractograph: IGC-AS internal Sn Nb3Sn strand 2838x872 638KB - JPG
1024x314 121KB - JPG
3-d (red-blue anaglyph)fractograph: IGC-AS internal Sn Nb3Sn strand - filaments with large external grains.
Nano-Treats! 3-d (red-blue anaglyph) fractograph of Nb3Sn layer deposited by Lance Cooley. 911x594 560KB - JPG
911x594 126KB - JPG
Nano-Treats! 3-d (red-blue anaglyph) fractograph of Nb3Sn layer deposited by Lance Cooley.
3-d (red-blue anaglyph)fractograph of Nb3Sn layer in high critical current OI-ST MJR Nb3Sn strand. 3020x1330 2MB - JPG
1024x450 165KB - JPG
3-d (red-blue anaglyph)fractograph of Nb3Sn layer in high critical current OI-ST MJR Nb3Sn strand. Unreacted strand supplied to the UW by Oxford Instruments Inc. - Superconducting Technology, Carteret, NJ.
side view of transverse fracture of OI-ST MJR Nb3Sn 1393x1125 1MB - JPG
950x768 186KB - JPG
3-d (red-blue anaglyph)fractograph - side view of transverse fracture of OI-ST MJR Nb3Sn after ramping to final heat treatment temperature. Strands are deliberately fractured to reveal grain size. FESEM. Unreacted strand supplied to the UW by Oxford Instruments Inc. - Superconducting Technology, Carteret, NJ.
3-d (red-blue anaglyph)fractograph of OI-ST high critical current density MJR Nb3Sn A15 layer. 2304x3052 2.7MB - JPG
580x768 142KB - JPG
3-d (red-blue anaglyph)fractograph of OI-ST high critical current density MJR Nb3Sn A15 layer. The strand has been ramped to final heat treatment temperature but has received its final HT. Unreacted strand supplied to the UW by Oxford Instruments Inc. - Superconducting Technology, Carteret, NJ.
3-d (red-blue anaglyph)fractograph of a large central void in a partially heat treated OI-ST MJR Nb3Sn sub-element. 1919x3124 1.9MB - JPG
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3-d (red-blue anaglyph)fractograph of a large central void in a partially heat treated OI-ST MJR Nb3Sn sub-element. Unreacted strand supplied to the UW by Oxford Instruments Inc. - Superconducting Technology, Carteret, NJ.
3-d (red-blue anaglyph)fractograph of A15 layer in SMI PIT Nb3Sn filament. 1510x1083 1.3MB - JPG
1024x735 170KB - JPG
3-d (red-blue anaglyph)fractograph of A15 layer in SMI PIT Nb3Sn filament. Note large interior grain layer but uniform grain size across main A15 layer. Unreacted strand supplied to the UW by Shapemetal Innovation B. V., Enschede, The Netherlands.
3-d (red-blue anaglyph)fractograph of SMI-PIT Nb3Sn filament. 4698x2349 1.6MB - JPG
1024x515 151KB - JPG
3-d (red-blue anaglyph)fractograph of SMI-PIT Nb3Sn filament. A chunk of filament has been pulled out allowing us to see both the longitudinal as well and the transverse microstructure. The now porous inner core was the source of the Sn (this design using a powder core containing Nb-Sn compounds). The next photo uses a higher magnification. FESEM. Unreacted strand supplied to the UW by Shapemetal Innovation B. V., Enschede, The Netherlands.
3-d (red-blue anaglyph)fractograph of SMI-PIT Nb3Sn filament 1024x695 997KB - JPG
1024x695 507KB - JPG
3-d (red-blue anaglyph)fractograph of SMI-PIT Nb3Sn filament. A chunk of filament has been pulled out allowing us to see both the longitudinal as well and the transverse microstructure. FESEM image. Unreacted strand supplied to the UW by Shapemetal Innovation B. V., Enschede, The Netherlands.
3d (blue-green anaglyph) fractograph of VAC bronze process ITER type Nb3Sn strand. 699x916 250KB - JPG
586x768 141KB - JPG
3d (blue-green anaglyph) fractograph of VAC bronze process ITER type Nb3Sn strand. These filament have fractured along their longitudinal (wire drawing) axis. Some have fracture across the center of the filament and show columnar grains growing in the direction of the unreacted Nb core. The initial (outer) Nb3Sn grains are equiaxed and where the fracture has not crossed the inner region there is the appearance of an entirely equiaxed layer.
Sub-element grouping of Nb3Sn filaments in bronze-process strand 680x1011 609KB - JPG
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Sub-element grouping of Nb3Sn filaments in bronze-process strand now viewed in 3d (blue-green anaglyph) fractograph. FESEM.
3d (blue-green anaglyph) fractograph of filaments in a VAC bronze-processed Nb3Sn strand. 708x1015 385KB - JPG
708x1015 1.8MB - TIF
3d (red-blue anaglyph) fractograph of filaments in a VAC bronze-processed Nb3Sn strand. FESEM.
3d (blue-green anaglyph) fractograph across fully reacted layer 3020x1330 5MB - JPG
1024x450 166KB - JPG
3d (red-blue anaglyph) fractograph across fully reacted layer of TWC high critical current density MJR Nb3Sn strand. The core of the filament (the original source of the Sn prior to reaction) is to the left. To the right there are some columnar grains where the Sn has begun to react with the Nb diffusion barrier. Outside the barrier is the Cu stabilizer matrix.Unreacted strand supplied to the UW by (Teledyne) Wah Chang, Albany, OR.
3d (blue-green anaglyph) fractograph of TWC high critical current density MJR Nb3Sn strand. 2073x3146 4.4MB - JPG
506x768 118KB - JPG
3d (red-blue anaglyph) fractograph of TWC high critical current density MJR Nb3Sn strand. This image shows part of a sub-element (core at the bottom, barrier at the top) that has been ramped up the final heat treatment temperature but has not recieved the final heat treatment. Much of the superconducting layer has been formed and the grains are small and equiaxed (except for a larger grained inner layer). The Nb3Sn grains fracture at their grain boundaries, providing the contrast required to analyze their size and distribution. The remaining unrected Nb is ductile and is pulled into the mountain ridges by the fracture process. Unreacted strand supplied to the UW by (Teledyne) Wah Chang, Albany, OR.
3d (blue-green anaglyph) fracture image of Sn breakout region of prototype Nb3Sn strand. 1751x1512 434KB - JPG
1024x767 208KB - JPG
3d (red-blue anaglyph) fracture image of Sn breakout region of prototype Nb3Sn strand. This image shows a parially metlted region of a high-Jc filament pack. The rest of the sub-element can be seen in the inset image. This is a fracture image so the complex phase is hanging in the void space.after reaction (it would not otherwise survive the fracture process.
3d (blue-green anaglyph) fracture image of Sn breakout region of prototype Nb3Sn strand. 6125x3081 2.7MB - JPG
1024x515 151KB - JPG
3d (red-blue anaglyph) fracture image of Sn breakout region of prototype Nb3Sn strand. This is a poster-sized image showing a parially metlted region of a high-Jc filament pack (detail above). The image is a montage of images taken at different magnifications. Only the break-out area is at full resolution.
image of a polished and etched cross-section of a Nb3Sn strand 620x675 180KB - JPG 3-d (yellow-left-eye/blue anaglyph) image of a polished and etched cross-section of a Nb3Sn strand that has been bent to failure. Strands tested at the University of Twente using the TARSIS device. The copper matrix has been etched back to reveal the location of cracked superconducting filaments.
Needles and Pills on the surface of a Nb3Sn filament 765x760 153KB - JPG 3-D Nb3Sn filament. (IGC-AS Internal Sn fusion type). "Needles and Pills" on the surface of a Nb3Sn filament, part of a study on HT environment. This 3D image was created from three images taken at different working distances by using the EPFL-BIG EDF plugin for ImageJ.

Videos and Animations

A different way to look at a hardness indent (in a multifilamentary Nb3Sn strand) as viewed using data from our Olympus OLS3100 Scanning Laser Confocal Microscope. Original image by Matt Jewell.

Last modified on 30 May 2017