Sandia Labs FY22 Laboratory Directed Research & Development Annual Report

FY22 ANNUAL REPORT

DOE SIMULATORS BENEFIT FROM DEVELOPMENT OF SELF-BREAK, HIGH-PRESSURE AIR One of the highest priorities for DOE simulators is to upgrade their reliability and repeatability. This requires accurate and predictive models of high energy and high-density environments. To create these environments, a new paradigm of power flow equipment and manufacture is necessary. Sandia researchers are investigating ways additive manufacturing can create designs that are quicker to load, less expensive to fabricate, and optimized to reduce post shot debris and damage. To that end, PEEK and ULTEM advanced commercial polymer materials were evaluated concurrently for possible use with the high-pressure housings, and computer numerical controlled machining techniques were investigated to help fabricate reliable multimegavolt switches. This operation,

SELF-ASSEMBLED SEASHELL-LIKE COATINGS CAN ACT AS LARGE AREA ROBUST DEBRIS SHIELDS FOR NEXT-GENERATION PULSED POWER DRIVERS.

New shield materials with exceptional mechanical properties are needed for next-generation pulsed power capability but are not readily available. Current shield materials involve the use of lithium and beryllium, which cause major concerns for post-recovery cleaning and environmental, safety, and health practices. A coating technology was developed to synthesize composite coatings using silica and sugar-derived carbon, which mimic the natural seashell laminate structures. These

coatings exhibited high thermal stability up to 1,650°C and exceeded the hardness of Spectra® by ~44%. The initial tests on the Z machine ride along showed promising results with coatings outperforming uncoated substrate. This composite material can be used in numerous applications in mechanical and thermal protections. For example, it can be used in the pulse power facility to protect diagnostic equipment and to protect satellites from micro-meteoroid and orbital debris impact. This technology won a 2022 R&D 100 Award in the Mechanical/Materials category (for the Ultra-Stable Thermally Excellent Advancement in Material Strength

technique ) and was published in MRS Advances in 2022. (PI: Guangping Xu)

(Above) Sandia researcher Guangping Xu uses a digital optical microscope to examine the synthesized composite coating, and (right) the coating technology used to synthesize composite coatings using silica and sugar derived carbon. (Photo by Bret Latter)

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