Neutron tomography offers insights into interior of teeth.

BERLIN, Germany: Imaging techniques based on neutron beams are rapidly developing and have become versatile non-destructive analysing tools in many fields of study. Researchers at the Helmholtz-Zentrum Berlin (HZB) have recently published a comprehensive overview of neutron-based imaging processes. Neutron tomography has facilitated breakthroughs in diverse areas, including dentistry.

The advantage of this method lies in the fact that neutrons can penetrate deeply into a sample without destroying it. In addition, neutrons can distinguish between light elements such as hydrogen and lithium, and substances containing hydrogen. Because neutrons themselves have a magnetic moment, they react to the smallest magnetic characteristics inside the material. This makes them a versatile and powerful tool for materials research. 2-D or 3-D images, called neutron tomograms, can be calculated from the absorption of the neutrons in the sample.

The researchers described how improvements in recent years have extended the spatial resolution down to the micrometre range. This is more than ten times better than the typical medical X-ray tomography. It is now also possible to take images more speedily, which makes observing processes in materials feasible.

Applications are of a wide range, such as the examination of teeth, observing the transport of lithium ions in batteries, strength analysis of industrial components, bones and the roots of plants, as well as non-destructive analysis of historical objects.

“Neutron tomography is extremely versatile. We are working on further improvements and hope that this method, which is in great demand, will also be available in modern spallation sources in the future,” said lead author Dr Nikolay Kardjilov at the HZB’s Institute of Applied Materials.

The study, titled “Advances in neutron imaging,” was published online in Materials Today on 3 May 2018, ahead of inclusion in an issue.

The study was conducted in collaboration with the European Spallation Source European Research Infrastructure Consortium in Sweden and the Technical University of Berlin in Germany.