Defense Systems Digest - 21 May 2019

Credit: Shayan Mookherjea, UC San Diego

Notable Technical Inquiry

What miniaturized cryptographic devices are available for transponder and radio applications in small UAVs?

DSIAC was asked to find small size, weight, and power (SWaP) cryptographic devices for Mode-5 transponders and radios in small unmanned aerial vehicle (UAV) applications. DSIAC...

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Shannon Foley, Ph.D., Human Effects Scientist, Joint Non-Lethal Weapons Directorate image

Voice From The Community

Shannon Foley, Ph.D., Human Effects Scientist, Joint Non-Lethal Weapons Directorate
Joint Non-Lethal Weapons Directorate, Human Effects Scientist,

As a subject matter expert at the Joint Non-Lethal Weapons Directorate, my primary duties include  technical and financial oversight of several programs and projects within the human effects portfolio,  as well as human effects research planning and strategizing. I also support technology and materiel development, combat development, and acquisition programs. I have been working with the DoD  since 2006 and previously served as a human systems engineer at the Naval Surface Warfare Center Dahlgren Division. I have a Ph.D. and M.Phil. in cognitive neuroscience from The George Washington University.

Featured News

Join us for a live webinar presentation on “Cryomilled 17-4 Stainless Steel Powder as Feedstock for Additive Manufacturing.”  


Wednesday, 29 May 2019 – 12:00 to 12:45 p.m. EDT

Additive manufacturing (AM) powders supplied by the manufacturer are gas atomized and supplied without post treatment.  
By including a pre-processing treatment prior to AM, the powder can be modified to improve the mechanical properties of the final build via a reduction in internal powder porosity and grain size refinement. A pre-processing treatment could also change how the powder behaves during the AM process. In this study, as-received gas atomized 17-4 SS powder was ball milled in liquid nitrogen (cryomilling) and then used as feedstock for powderbed fusion (PBF) AM. The effect of powder pre-processing treatment on powder flow and morphology and how changes to influence the PBF process and subsequent defect formation in finished parts was examined. Finished parts were characterized through microcomputed tomography and optical microscopy, while the effect on material characteristics was examined via x-ray diffraction and electron microscopy.