Applied Radiation

Upgrade of the neutron beam line instruments at the SAFARI-1 nuclear research reactor includes the installation of a modernised neutron radiography/tomography facility to contribute to the applications in the rest of this page.

Non-Destructive Examination

Neutron imaging is a non-destructive examination (NDE) technique that is complementary to X-ray imaging, in providing 2D and 3D information. Deep penetration of dense materials by neutrons allows for the inspection of metal components manufactured from dense materials such as Ti and W turbine blades, welds within thick steel components, etc., as quality control technique. The aircraft, motor, manufacturing and forensic industries are key beneficiaries in the application of neutron imaging.

Hydrogen Economy – Fuel Cells and hydrogen storage

The sensitivity of neutrons to light element such as hydrogen has direct application in the investigation of hydrogen Polymer Electrolyte Membrane (PEM) fuel cells and electrolysers, to follow and optimise water management within such devices using neutron imaging.  Hydrogen is important as an energy converter and carrier of electric power in PEM devices earmarked for the automotive industry. This requires optimisation of the structural stability as well as spatial and temporal variations of hydrogen concentration in metal hydride composite prototypes during cyclic hydrogenation.

A local capability will contribute to expanding the South African localization and research capacity initiatives in support of the hydrogen economy.  This would also benefit the use of Platinum Group Metals (PTM) strategic resources of South Africa.

Agriculture

Neutron Imaging is suitable to investigate water distribution in small and/or thin plant materials, which determines a broad field of applications of this method in various field of applied plant science. It supports research optimizing agricultural harvests in relation to the minimum quantity of water necessary for the plant to develop through neutron images of the root-soil system not possible through the other techniques. Neutron Imaging also allows for the direct visualisation of water flow and the calculation of water flow rates in plants with a high resolution at the tissue level.

Paleosciences

Fossils and fossil bearing materials are in principle irreplaceable and are globally a scarce commodity. As South Africa is being considered and known to be the “Cradle of Mankind”, and Necsa is located within the Cradle, the value of a Neutron imaging at Necsa is enhanced as neutron penetration through dense breccia materials is possible to reveal hidden fossil materials in a non-destructive manner.  Neutron Imaging will add value to the paleoscience community as rare fossil are being investigated non-invasively where other NDT techniques fail. Evolutionary studies in the development of e.g. the cochlea, brain, sinus and behaviours become possible using cold neutron imaging.

Archaeology

The application of Neutron imaging techniques support restoration and conservation planners to understand historical construction techniques, reveal poor restoration work, determine the authenticity of the artefacts (forgeries), the composition and manufacturing technologies and state of corrosion. Several artefacts are made of bronze or lead and results in poor X-ray transmission while neutrons can penetrate easily for easy non-invasive analysis of the condition of the artefact.

Civil Engineering

The durability of concrete and water transport through concrete structures are essential parameters for civil engineers of the characteristics of concrete. Concrete integrity is specifically important as barrier in nuclear waste encapsulation where neutron imaging, as non-destructive analytical technique, easily detect the free water movement and distribution.

Metallurgy

Neutron imaging can provide more accurate information on a sample if carried out with selected neutron energies. The proof of principle experiment for energy-selective imaging was carried out at ISIS. Use of this method requires a neutron spectrum. In this method, the transmission signal is recorded position sensitively depending on the neutron energy being varied. Due to Bragg scattering in the crystal lattice of the material in the sample, a diffraction contrast is observed in the transmission images. This contrast allows to distinguish between different crystallographic modifications of the material and hence to make phase separation in 3D, non-destructively. The diffraction contrast provides information about the presence of mechanical residual stresses and textures in the sample.

Nuclear Engineering

Neutron imaging is applied in the quality assurance of nuclear materials and processes throughout the nuclear fuel cycle especially during I & PIE processes including within the manufacturing of nuclear fuel for the new MPR. Neutron imaging of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Applications include examination of nuclear waste, nuclear fuels, cladding, control elements, and other critical components.

Petro-Physics (Hydrocarbon – oil industry)

Knowing the physical properties of rock, enhances the knowledge of engineers to predict more accurately e.g. the flow of water / gas or oil, the production rate and/or capacity of reservoirs and the composition of resources beneficial and important to geo- and petro-physicists. The capability and ability of neutron imaging to obtain information about porous media and to validate existing data obtained through conventional methods bears significant interest to a wide range of processes, such as secondary and tertiary oil recovery processes, salt water intrusion in coastal aquifers, contaminant transport in groundwater and packed-bed processes while in oil bearing rocks, quantitative estimates of fluid concentration can be made. An advantage of neutron imaging in oil bearing reservoir rocks is that a good estimate of total versus effective porosity can be made. This estimate is an important addition to the conventional methods of determining porosity. Finally, dynamic NRAD can enable the reservoir engineer to evaluate the behaviour of a two-phase flow front through a reservoir rock by direct imagery.

Geosciences

The physical properties of rocks and especially these from borehole cores, somehow tell the story of the earth, its mineral composition and sometimes how porous, cracked, wet and how fluid flows through the matrix. However, neutrons have the ability to penetrate more easily geological laboratory samples and provide important information to geologist and scientists on a non-destructive basis. Neutron imaging finds its application also into the area of thin sectioning of borehole cores with fine 3D-resolution as tomographic imaging complements the conventional destructive analytical thin sectioning of core samples.

Support to Science and Technology – Knowledge generation

The availability of neutron beam line scattering instruments and irradiation positions for material damage support technological programmes not only at universities but also at research institutions like MINTEK, CSIR and iThemba LABS and at industries such as Eskom, Denel, Sasol, Transnet with the mining and manufacturing industries also very probable users. South African universities in general would be able to perform high quality experimental measurements without the struggle to compete for beam time with other international researchers and to obtain funding for international trips. The availability of neutron beam time could be a key factor to facilitate cooperation with other international institutions, mainly by co-authoring publications in journals that will expose South African researchers to cutting-edge technology and will bring valuable knowledge and experience to the country.

Support of National System of Innovation: (Post Graduate Development) Human capital development

Several Higher Educational Institutions (HEI) has been training post-graduate students in Nuclear Engineering. Efforts to produce the much needed local human capacity to face the planned South African nuclear growth can hardly succeed without the support of a nuclear facility where the students can get in contact with reality and apply their freshly acquired knowledge to solve real problems. A local neutron source where the seasoned South African researchers can regularly perform their measurements will allow these mentors to introduce their post-graduate students or young colleagues to the different measurement techniques, and give them the opportunity to get hands-on experience, with practically no limitations. The availability of and easy access to neutron scattering instruments, neutron activation analysis facilities, and general purpose irradiation positions, will facilitate and promote the training of quality professionals, preparing them to face highly complex technological problems, and therefore enhancing the overall output of science and technology in the country.