Abstract

When the synchrotron beamline Eddi (Energy Dispersive DI ffraction) [1] had to make way for a new storage ring concept at BESSY II in mid-2018 after almost 15 years of successful operation, materials research in the hard X-ray range had to continue at HZB under laboratory conditions. The way back from the synchrotron to the laboratory requires sophisticated strategies aimed at fully exploiting the photon flux provided by conventional X-ray tubes [2] on the one hand, and at using powerful high-flux X-ray sources [3] on the other hand.

The present talk is about the second strategy. Since 2017 HZB operates two measurement stations Limax-70 and Limax-160 (LI quid M etal Anode X -rays) with photon energies up to 70 keV and 160 keV, respectively, making use of both the characteristic X-ray lines at 9 keV (GaKα) and 24 keV (InKα) and the white Bremsstrahlung spectrum in the angle-dispersive (AD) and the energy-dispersive (ED) mode. Suitable beam optics play a key role in focusing as much of the spectrum emitted by the MetalJet source as possible onto the sample. While pinhole collimators only cut out a small fraction of the emitted radiation cone, two-dimensional beam-shaping optics such as Montel multilayer mirrors and polycapillary lenses can be used to collect larger parts of the spectrum.

Since (industrial driven) research at the Eddi beamline, which was mainly dedicated to ED residual stress analysis in the materials near surface zone, is continued at the MetalJet sources, a direct comparison between synchrotron and laboratory diffraction facilities becomes possible. Selected examples from this and related areas of materials research will be used to discuss the prospects, challenges and limitations of laboratory-based experiments.

[1] Ch. Genzel, I. A. Denks, J. Gibmeier, M. Klaus, and G. Wagener. “The materials science synchrotron beamline EDDI for energy-dispersive diffraction analysis”. In: Nucl. Instr. Methods in Physics Research A 578 (2007), pp. 23–33.

[2] D. Apel, M. Meixner, A. Liehr, M. Klaus, S. Degener, G. Wagener, C. Franz, W. Zinn, Ch. Genzel, and B. Scholtes. “Residual stress analysis of energy-dispersive diffraction data using a two-detector setup: Part I — Theoretical concept”. In: Nuclear Inst. and Methods in Physics Research A 877 (2018), pp. 24–33.

[3] Ch. Genzel, M. Meixner, D. Apel, M. Boin, and M. Klaus. “Nondestructive residual stress depth profile analysis at the inner surface of small boreholes using energy-dispersive diffraction under laboratory conditions”. In: J. Appl. Cryst. 54 (2021), pp. 32–41.