1. |
- Tremsin, A. S., et al.
(författare)
-
High-Resolution Neutron Counting Sensor in Strain Mapping Through Transmission Bragg Edge Diffraction
- 2011
-
Ingår i: IEEE Sensors Journal. - 1558-1748. ; 11:12, s. 3433-3436
-
Tidskriftsartikel (refereegranskat)abstract
- High-resolution neutron counting sensors with microchannel plates coupled to a Timepix readout enable high spatial (similar to 55 mu m) and temporal (similar to 1 mu s) accuracy for each detected thermal and cold neutron. One of the attractive applications for those sensors is the high-resolution strain mapping in engineering samples through transmission Bragg edge diffraction. The unique combination of high detection efficiency (up to 70%), high spatial and temporal resolution of, detectors enable similar to 100 mu m strain mapping with similar to 100 mu strain accuracy. We present the results of proof of principle measurements performed at ROTAX beamline at ISIS spallation neutron source. Strain map of a bent steel sample is measured with very high spatial resolution. The same sensors enable high-resolution nondestructive studies in such diverse areas as neutron microtomography, dynamics of fuel injection, material composition, archaeology, water propagation and many others.
|
|
2. |
|
|
3. |
- G.M.Kalvius, F.E.Wagner, D.R.Noakes, E.Schreier, R.Wäppling, U.Zimmermann, W.Schafer, W.Kockelmann, I.Halevy, J.Gal
(författare)
-
Magnetic behavior of YFe/sub x/Al/sub 12-x
- 2003
-
Ingår i: Physica B. ; 326:1-4, s. 460-464
-
Tidskriftsartikel (refereegranskat)
|
|
4. |
|
|
5. |
- Lehmann, E. H., et al.
(författare)
-
The energy-selective option in neutron imaging
- 2009
-
Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 603:3, s. 429-438
-
Tidskriftsartikel (refereegranskat)abstract
- In the past, neutron imaging investigations have been mostly performed in "integrating mode", which averages over the full applied neutron energy spectrum. This article describes four different methods and devices of obtaining energy selectivity in the thermal to cold energy range, which allow a new approach in neutron imaging. Two principles have been used and tested: (a) selection of neutrons by suppression of contribution of other spectral parts; (b) using the flight-time information in distance from the source. For the (a) option, three different devices have been exploited practically. Information about material properties can be revealed that cannot be obtained in integrating mode. The energy-dependent transmission measurements make use of the Bragg edges in the total cross-sections of materials. Energy-selective radiography has vast potential for contrast variation, and for mapping structural properties such as crystallographic texture and residual strains with high spatial resolution. The obtained images highlight new opportunities in materials and engineering research, in comparison and complementary to what can be obtained by neutron scattering. There is likely to be an increasing need for implementing time-of-flight neutron imaging at present and future pulsed spallation sources, where the energy range can be selected almost without limitations. In this paper we attempt to give an overview over the current state of the art of energy-selective imaging and the experimental configurations required. (C) 2009 Elsevier B.V. All rights reserved.
|
|
6. |
- Oji, U.K., et al.
(författare)
-
Implementation of time of flight polarized neutron imaging at IMAT-ISIS
- 2023
-
Ingår i: Materials & design. - : Elsevier. - 0264-1275 .- 1873-4197. ; 235
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we report the first case of design and implementation of a polarized neutron imaging option on the Imaging and Materials Science & Engineering Station (IMAT). This is a significant addition to the capabilities of the station that allows the characterization of advanced magnetic materials for different engineering applications. Combining its time-of-flight feature with a polarized beam yields data that facilitate both quantitative and qualitative analysis of magnetic materials. Using the simple field of an aluminium solenoid, we perform a characterization of the new setup. In addition, we present polarized measurements of additively manufactured (AM) MnAl samples where the magnetic anisotropy due to the fabrication process has been investigated as a first scientific application of the setup. The results indicate that the anisotropy of the material can be engineered through variation of the AM fabrication parameters.
|
|