Methods
I’m a materials scientist — so why should I care about neutrons?
Short answer:
Neutrons allow us to non-destructively investigate the structure and dynamics of matter across a wide range of length scales — from atomic (1 Å) to macroscopic (millimeters)!
Longer answer:
Despite being challenging (and costly) to produce, neutrons offer unique advantages that make them an invaluable probe in materials science and many other fields:
- Ideal wavelength: Neutrons have wavelengths comparable to interatomic distances, making them perfect for studying molecular structures. The interference patterns from scattered neutrons reveal the spatial arrangement of atoms and molecules in a sample.
- Electrically neutral: Because neutrons carry no charge, they interact only weakly with matter. This minimizes beam-induced damage and allows for the investigation of thick or dense samples that would be inaccessible with other techniques.
- Magnetic sensitivity: Neutrons behave like tiny magnets, enabling the study of magnetic field distributions and magnetic properties of materials. For example, different phases in metallic alloys often exhibit distinct magnetic behaviors — a key insight for materials development.
- Isotope sensitivity: Chemically, isotopes of an element behave similarly. However, neutrons interact differently with each isotope. This property is exploited by selectively substituting atoms to act as "markers", allowing detailed studies of:
◦ Crystallographic structures
◦ Hydrogen storage materials
◦ Biological systems
◦ Lithium distribution in electrochemical devices
The following instruments are available:
Contact: Dr. Weimin Gan
Contact: Dr. André Heinemann
Contact: Dr. Jean-François Moulin
Materials Science Lab
for sample preparation and complementary characterisation
Contact: Armin Kriele
The most important methods:
• Diffraction – strain analysis
For measurements of stresses in the interior of materials and components.
• Diffraction – texture measurements
For measurements of crystallographic textures.
• Diffraction – phase analysis
For the quantitative determination of the phase composition of a material.
• Small-Angle Neutron Scattering (SANS)
For the analysis of nanostructures in the bulk, e.g. precipitates.
• Neutronen-reflectometry and small-angle scattering under grazing incidence (GISANS)
For the analysis of nanostructuires at interfaces, e.g. coatings.