https://hdl.handle.net/11256/1 2026-03-09T06:04:09Z 2026-03-09T06:04:09Z Deschepper, Daniel Gray, David Moy, Paul Walter, Timothy Jensen, Robert Pollum, Marvin Hellerman, Edward Kriley, Joseph Nakajima, Masa Rearick, Brian https://hdl.handle.net/11256/1005 2024-06-11T17:23:05Z

Testing Military-Grade Adhesive in Extreme Loading Conditions Deschepper, Daniel; Gray, David; Moy, Paul; Walter, Timothy; Jensen, Robert; Pollum, Marvin; Hellerman, Edward; Kriley, Joseph; Nakajima, Masa; Rearick, Brian Military performance requirements for adhesives have been traditionally derived to fulfill niche defense needs in harsh operational environments with little consideration for dual-use commercial potential. The drawback with this approach is dwindling defense acquisition access to leading-edge commercially sustainable products, as the market drivers for purely non-defense applications are significantly larger. MIL-PRF-32662, Adhesive, High-Loading Rate, for Structural and Armor Application, is based on a decade of rigorous research efforts to statistically correlate the complex ballistic response of adhesively bonded armor assemblies to universally translatable and commercially relevant mechanical properties. These military performance thresholds were deliberately defined at just beyond state-of-the-art based on a statistical survey of commercially available adhesives. The end results are performance criterion for MIL-PRF-32662 that are difficult, but not impossible, to meet with the intention of attracting commercial interest. The objective of this experimental work is to quantify adhesive performance defined by “harsh military operational environments” against a suitable non-military harsh use condition. The result of this study shows a 32% increase in static load retention strength of an adhesive formulated to meet MIL-PRF-32662 Group 1 requirements when tested in the tensile butt joint geometry specified by Guinness World Records. These results offer further encouragement to explore the potential of military performance specifications as agents of change in leading technical advances in dual-use market sectors.

https://hdl.handle.net/11256/1002 2023-09-07T20:22:57Z

PPG PR-2930 MIL-PRF-32662A qualification data PPG PR-2930 MIL-PRF-32662 test data

Mohan, Soumya Pilchak, Adam L. Kalidindi, Surya R. https://hdl.handle.net/11256/995 2021-08-09T04:39:56Z

Use of spherical nanoindentation protocols to study the anisotropic mechanical response of alpha-beta single colonies in Ti-6Al-4V alloy Mohan, Soumya; Pilchak, Adam L.; Kalidindi, Surya R. The recently developed spherical nanoindentation stress-strain protocols were employed in this study to investigate systematically the anisotropic elastic and yield response of the α-β single colonies in a Ti-6Al-4V alloy. This was accomplished by indenting colonies with different lattice orientations of the α (measured by electron back-scattered diffraction) in the polycrystalline sample. It is seen that the employed protocols are capable of providing reliable and consistent information on the anisotropy of the colonies in a high-throughput manner, compared to the other approaches being explored in current literature. Furthermore, the responses measured in this study have been compared against similar measurements on differently oriented grains of primary α. It was noted that the α-β colonies exhibit distinctly different elastic and plastic anisotropy compared to the primary α grains. A dip in the indentation yield properties at 45 degrees declination angle is observed, and a lack of anisotropy is observed in the elastic properties.

Cummock, Nicholas https://hdl.handle.net/11256/993 2020-12-15T21:26:59Z

HMX microstructural data of beta, delta, and beta-reversion Cummock, Nicholas X-ray computed tomography of large HMX crystals, and scanning electron microscopy of focused ion beam milled/polished small HMX crystals of varying solid phases.