In Situ Experiments with Synchrotron High‐Energy X‐Rays and Neutrons

Abstract

High‐energy X‐rays offer the large penetration depths that are often required for determination of bulk properties in engineering materials research. Photon energies of 150 keV and more are available at synchrotron sources, depending on storage ring and insertion device. In addition, synchrotron sources can offer very high intensities on the sample even at these energies. They can be used not only to obtain high spatial resolution using very small beams, but also high time resolution in combination with a fast detector. This opens up possibilities for a wide range of in situ experiments. Typical examples that are already widely used are heating or tensile testing in the beam. However, there are also more challenging in situ experiments in the field of engineering materials research like e.g. dilatometry, differential scanning calorimetry, or cutting. Nevertheless, there are a number of applications where neutron techniques are still favorable and both probes, photons and neutrons, should be regarded as complementary. A number of in situ experiments were realized at the GKSS synchrotron and neutron beamlines and selected examples are presented in the following.

In Situ High-Energy X-ray Diffraction during Hot-Forming of a Multiphase TiAl Alloy

“…Several heating and hot compression tests were performed using a DIL 805A/D quenching and deformation dilatometer (TA Instruments, Hüllhorst, Germany) that had been modified for working in the Helmholtz-Zentrum Geesthacht synchrotron beamline HEMS at PETRA III, DESY (Hamburg, Germany) [17,22]. This setup is displayed in Figure 1a.…”

“…Over the last decade, new high-energy synchrotron sources were constructed, which, in combination with advanced sample environments, provide novel tools and analysis methods for engineering and materials science [16][17][18]. Such synchrotron sources offer the possibility for time-resolved in situ studies during materials processing [19,20].…”

In Situ Characterization Techniques Based on Synchrotron Radiation and Neutrons Applied for the Development of an Engineering Intermetallic Titanium Aluminide Alloy

“…For in situ investigations of the phase transformation behavior of titanium aluminides, high-energy X-ray diffraction (HEXRD) has evolved into a powerful and versatile tool [48,50,51,[63][64][65][66]. At synchrotron radiation sources, a white X-ray beam is produced by the deflection of charged particles, either electrons or positrons, by means of a bending magnet or an insertion device, i.e., a wiggler or an undulator, as shown in Figure 4 [67].…”

“…An area detector at the front captures sets of Debye-Scherrer rings [52]. The photograph on the right shows the quenching and deformation dilatometer [64,66] as an example of a versatile sample environment installed at the PETRA III High Energy Materials Science (HEMS) beamline. In the insert at the top, a heated specimen is glowing during an in situ experiment.…”

“…For this purpose, a variety of sample holders and furnaces is currently available. For a large part of the HEXRD experiments presented in this review, a quenching and deformation dilatometer supplied by Bähr Thermoanalyse GmbH, Germany (now TA Instruments), with built-in windows for the X-ray beam, was used (see the photograph in Figure 4) [64]. In this setup, thermal expansion curves and diffraction patterns can be measured simultaneously.…”