X-Ray Diffraction Measurements on Laser-Compressed Polycrystalline Samples Using a Short-Pulse Laser Generated X-Ray Source

Technical Report · Sat Sep 01 00:00:00 EDT 2018

DOI:https://doi.org/10.2172/1474265· OSTI ID:1474265

Schollmeier, Marius S. ^[1]; Field, Ella Suzanne ^[1]; Galloway, Benjamin Robert ^[1]; Kimmel, Mark W. ^[1]; Rambo, Patrick K. ^[1]; Schwarz, Jens ^[1]; Ao, Tommy ^[1]; Kalita, Patricia E ^[1]; Seagle, Christopher T ^[1]; Morgan, Dane V. ^[2]; Long, Joel ^[3]

---

1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Mission Support and Test Services, LLC (MSTS), Los Alamos, NM (United States)
3. Model World LLC, Albuquerque, NM (United States)

Existing models for most materials do not describe phase transformations and associated lattice dy- namics (kinetics) under extreme conditions of pressure and temperature. Dynamic x-ray diffraction (DXRD) allows material investigations in situ on an atomic scale due to the correlation between solid-state structures and their associated diffraction patterns. In this LDRD project we have devel- oped a nanosecond laser-compression and picosecond-to-nanosecond x-ray diffraction platform for dynamically-compressed material studies. A new target chamber in the Target Bay in building 983 was commissioned for the ns, kJ Z-Beamlet laser (ZBL) and the 0.1 ns, 250 J Z-Petawatt (ZPW) laser systems, which were used to create 8-16 keV plasma x-ray sources from thin metal foils. The 5 ns, 15 J Chaco laser system was converted to a high-energy laser shock driver to load material samples to GPa stresses. Since laser-to-x-ray energy conversion efficiency above 10 keV is low, we employed polycapillary x-ray lenses for a 100-fold fluence increase compared to a conventional pinhole aperture while simultaneously reducing the background significantly. Polycapillary lenses enabled diffraction measurements up to 16 keV with ZBL as well as diffraction experiments with ZPW. This x-ray diffraction platform supports experiments that are complementary to gas guns and the Z facility due to different strain rates. Ultimately, there is now a foundation to evaluate DXRD techniques and detectors in-house before transferring the technology to Z. This page intentionally left blank.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1474265
• Report Number(s): SAND--2018-10612; 668183
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE