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Resonant ultrasound spectroscopy (RUS) is an efficient, nondestructive technique to study the elastic properties of solids. A low-temperature (2-300 K) probe has been assembled and tested at the NOMAD beamline at the Spallation Neutron Source at Oak Ridge National Laboratory to assess the probe's neutronic properties, data acquisition system, and compatibility with existing sample environment. A case study on a bulk metallic glass, La 65 Cu 20 Al 10 Co 5, served to benchmark both hardware and software developments. The elastic constants of the metallic glass were determined as a function of temperature between 4 and 300 K and were used to guide neutron diffraction measurements at NOMAD. Tracking of a specific RUS peak center frequency and width enabled live monitoring of the sample temperature evolution that lagged thermometry by upwards of 40 K near room temperature. Assembly of a high-temperature (300-875 K) probe is underway and both probes are scheduled to be available to users by late-2021. Our aim is to provide users with live monitoring of an intrinsic variable at the neutron scattering beamlines, in addition to existing controls, to monitor the state of their samples and its elastic moduli and make informed decisions in real time.

Resonant ultrasound spectroscopy (RUS) is an efficient nondestructive technique to study the elastic properties of solid materials. In principle, the full elastic tensor can be determined for regularly shaped solids (e.g., sphere, cuboid, cylinder). Here, we report our progress in developing RUS probes for in situ neutron scattering at beamlines of the Spallation Neutron Source at Oak Ridge National Laboratory. A low-temperature (2–300 K) probe has been assembled and tested at the NOMAD and SEQUOIA beamlines to assess the probe’s neutronics, data acquisition system, and compatibility with the existing sample environment. Our discussion will include how the probe and data acquisition system operate as well as results for two measurements: bulk metallic glass (La65Cu20Al10Co5) and bismuth-antimony (Bi0.89Sb0.11 [1]). Assembly of a high-temperature (300–875 K) probe is currently underway and both probes are scheduled to be available to users by late-2021. Our aim is to provide users with live monitoring of an intrinsic variable at the neutron scattering beamlines, in addition to existing controls, to monitor the state of their samples and make informed decisions in real time. The probe developments are accompanied by developments of data acquisition and analysis software. 1. D. Vu et al., arXiv: 1906.02248 [cond-mat.mtrl-sci] (2019).