With diffraction methods a variety of structural properties in the micro and nanometer range can be investigated.
Residual stress analysis using neutron and X-ray diffraction
For the investigation of load, composite and residual stresses of materials and components, we at HZB use complementary methods for illuminating different penetration depths. By means of energy-dispersive X-ray diffraction, internal stress depth gradients from the surface are made visible in a depth of approximately 100 μm (for example for steels). These can also be resolved in multiple layers of coated components. By contrast, neutron diffraction can be used to analyze stresses in several millimeters (for aluminum even in several centimeters). This provides a broad spectrum for applications from various industrial sectors, for example:
- Multilayer coating system on the surface of cutting tools
- Components for the automotive industry, as well as for aerospace
- electronic components
- Components from additive manufacturing
Reflectometry for the investigation of X-ray optics
Mirrors, grids and crystals are the basis for soft X-ray optics and technology. At HZB, we routinely measure the quality of optical beamline elements, the reflectivity of mirrors, the efficiency of gratings, and the scattering properties of ultra-smooth surfaces. Our UHV reflectometer is a multi-purpose tool for determining the optical properties of samples in transmission or reflection. The reflectance can be determined at a fixed photon energy as a function of the angle of incidence or, conversely, as a function of the energy for a particular angle of incidence. The samples can have any size from a few square millimeters to macroscopic optical elements.
Small angle scattering
ASAXS analysis and the derived structural model of a RuSexOy catalyst for fuel cell applications. RuSexOy electrocatalysts with a cluster-like selenium distribution on the surface of carbon black-supported ruthenium nanoparticles are suitable substitutes for platinum on the cathode side of methanol fuel cells.
Nanostructures and nanostructured materials play an increasingly important role in almost all areas of industry. Along with this, the importance of methods for characterizing such materials continues to increase. Small-angle scattering helps to capture a variety of parameters in the nanometer range. It is able to investigate inhomogeneities in a material in the size range from 0.5 nm to more than 1000 nm.
These can be both nano-particles entrapped in a material and differences in the density, composition or magnetization of the material. So can be z. For example, determine size and distance distributions, morphology and composition as well as the volume fractions of these inhomogeneities.