The SoM group provides facilities for a range of X-ray scattering, imaging and spectroscopy experiments, relevant to the fields of energy research, catalysis, engineering, metallurgy, nanoscience and other fields of advanced technology. In addition to traditional technological subjects, the SoM group also covers X-ray imaging studies for biology, archaeology and palaeontology.

The materials science beamline ID11 continues to welcome a wide range of user experiments. The new nanofocus end-station is now complete and has been used for several experiments. These include single crystal, total scattering and grain mapping experiments in several scientific areas, including metallurgy, chemistry, high pressure and geology. The ID11 team continues to develop software for grain mapping. There have been significant improvements to the MATLAB-based diffraction contrast tomography code in order to process data from twinned samples and with a greater tolerance for deformation [1]. Work has begun on upgrading the Fable python codes so that they can be run on python3 in the future.

ID15A is devoted primarily to operando studies in materials chemistry and materials engineering, with two dedicated experimental hutches. The materials chemistry hutch, operational since November 2016, is optimised for the rapid acquisition of multidimensional data on working chemical reactors, novel batteries, and other systems of interest to the chemical and energy sectors. X-ray diffraction measurements can now be combined with X-ray fluorescence measurements, absorption/phase contrast imaging, infra-red spectrometry and mass spectrometry. A gas delivery system for catalysis or other chemistry experiments is also available. Over the last few years, new software tools have been developed for the automation of data acquisition and processing, allowing users to fully exploit the rich multidimensional data collected via XRD computed tomography (XRDCT) with minimal expert intervention. A collaboration contract has been established with Finden Ltd. (UK) for the further development of XRDCT. The materials engineering station received its final instrumentation during summer 2017 and is now fully functional, offering energy or angular dispersive diffraction and ultra-fast imaging using monochromatic or pink beams, with X-ray energies up to several hundred keV. A collaboration with Manchester University (UK) has been established in the field of engineering science.

Microtomography beamline ID19 has further expanded its capabilities, welcoming users for dynamic experiments such as shock studies or additive manufacturing. The laser safety system was installed, allowing users to perform time-resolved studies using phase contrast imaging with large propagation distances combined with laser irradiation. The pulsed laser, purchased in 2002 (Brilliant B by Quantel, 850 mJ at 1064 nm, 20 ns pulse width), was refurbished and is now equipped with frequency doubling modules as well as optical focusing elements. Within the frame of the long-term proposal MI-1252 (Eakins et al., Oxford University and Imperial College London, UK) a Split-Hopkinson pressure bar was developed and provided by the Nuclear Research Center NEGEV (NRCN) in Israel. It will allow users to study the dynamic response of materials to stress. In 2017 an experiment with a two-stage gas gun demonstrated that impact velocities up to 4.7 km/s are possible for synchrotron experiments. In addition to the selected articles, one should note the paper by Hänschke et al. [2] on in situ imaging of dislocations in semiconductor wafers.

In January 2017 the stalwart high-precision powder diffractometer on beamline ID22 was retired. The machine, manufactured by Rotary Precision Instruments (Bath, UK), was delivered to the ESRF in December 1994. It was tested on the Swiss Norwegian Beamline BM01B before being installed on BM16, complete with its nine-crystal multianalyser stage. SNBL, with whom the BM16 team worked in the development of the diffractometer, runs the sister machine, also acquired from RPI. The BM16 diffractometer has followed the ESRF high-resolution powder diffraction beamline around the ring, to ID31 in 2002, and to ID22 in 2014. Hundreds of papers have resulted from measurements made with this diffractometer. As part of the upgrade programme and the move from ID31 to ID22, and with a view to the EBS upgrade and developments in detector technology, a new diffractometer was procured, equipped with the latest drive electronics and advanced mechanics from LAB Motion Systems in Belgium. After a brief commissioning period the new diffractometer has been in successful user operation all year.

The high energy beamline for buried interface structures and materials processing, ID31, just finished its second year of operation. In order to reveal the interplay between microscopic material properties and macroscopic device performances, ID31 offers a portfolio of hard X-ray characterisation techniques combined with unique sample environment systems. For example, during 2017 first user experiments were performed using the recently acquired fuel cell test station to characterise fuel cells according to industrial standards with X-ray diffraction data during the operation. A new operando method for surface structure determination, transmission surface diffraction (TSD), was developed, where surface diffraction rods can be measured in transmission geometry (see page 134). This allows to map the local surface properties with micrometre spatial resolution. A new high throughput powder diffraction system committed mainly for industrial use was commissioned. A robotic sample changer allows the collection of diffraction data via an area detector from thousands of samples per hour with excellent powder averaging thanks to a shaker system implemented on the robot arm. The beamline is now also equipped with laser safety system for in operando additive manufacturing studies.

In 2017, Council selected four new EBS upgrade beamlines, including the hard X-ray diffraction microscopy project. X-ray diffraction microscopy, or dark field X-ray microscopy, is a new technique to study the hierarchical structure of materials over length scales from 1 mm to below 100 nm [3,4]. By using Bragg diffraction, it is sensitive to crystallographic details such as strain and grain or domain orientation that are difficult to assess with other techniques. A second EBS beamline integral to the SoM group is the BM18 project: a high throughput large field phase contrast tomography beamline for applications from industry, materials research, engineering, biology and cultural heritage. The technical design of this beamline is already well advanced. The infrastructure work will start during the summer shutdown 2018 and will be followed by the beamline assembly phases during the long shutdown, 2019.

V. Honkimäki

 

References

[1] N. Viganò et al., Journal of Applied Crystallograpgy 49, 544-555 (2016).
[2] D. Hänschke et al., Phys. Rev. Lett. 119, 215504 (2017).
[3] H. Simons et al., MRS Bulletin 41, 454 (2016).
[4] H. Simons et al., Nat. Commun. 6, 6098 (2016).