Research-Single Source Information Extraction: 'Microwave Absorbing Properties of Metallic Glass..'

Bartolucci (2011) is a technical report [ARWSB-TR-11022] obtained from the Defense Technical Information Center (DTIC). Per the abstract, this study was performed to study the "microwave absorption characteristics of metallic glass/polymer composites.. (p.7)". The metallic glass/polymer composite is a "high magnetic permeability cobalt-based metallic glasses dispersed in epoxy matrices (p.7)" and "measured the reflection loss behavior of the composites in the C-band and X-band spectrum. (p.7)".

Bartolucci (2011, pp. 7-9): Background

The author, Bartolucci (2011), begins this section by providing the EM spectrum frequencies (0.3GHz-300Ghz) which span from radio to far-infrared (X-band==8-12 Ghz). Noting the beginning of research in the 1930s, Bartolucci (2011) lossy materials (energy dissipative/transferative;e.g., "carbonyl iron and ferrites (p.7)") have played a role in stealth technology and EM shielding applications. With stated recent research involving nano-particles, polymers, and other metamaterials. Next, the author says that "Radar absorbing materials work by reducing the amount of reflected energy to the radar by means of absorption processes. " and can also consist of dielectric or magnetic materials that impede the EM wave. The author ties this to the complex permittivity and the complex permeability and states that the process involved with lossy materials consists of the transfer of energy from a microwave frequency to the atoms of a material, which causes the molecular dipoles to oscillate.

When describing metallic glasses or amorphous metals, Bartolucci (2011, p.7) compares them to a frozen liquid with an atomic structure containing no long-range atomic order (i.e., amorphous); and equates attractive properties "

such as high strength and modulus and interesting electrical and magnetic properties. (p.7)". The author makes a note of other studies (REF WORD: annealing) before also making a note of recent studies involving nanotubes and nanoparticles. Of importance on page 9, Bartolucci (2011) states, "This type of modeling analysis was intended for this project, however, due to difficulties in measuring the permeability of the composites, the analysis was not performed."

Bartolucci (2011, pp.9- 13): Experimental Procedure and Results (pp.13-25)

The author outlines his procedure on pages 9 to 13 in exacting detail (see for complete parts of each) as:

"Two cobalt based metallic glasses were used in this project. The first composition was made from mechanical alloying of amorphous powders of cobalt, iron and silicon. The “powder to powde ” materials were 85Co-10Si-5Fe (NanoAmor, Houston, TX) by weight. These powders had a density of approximately 6.88 g/cc. The second metallic glass composition was made from milling MetGlas 2714A (MetGlas, Conway, SC) metallic glass ribbon. This ribbon material had a nominal composition of 85Co-9Si-4Fe-1Ni-1B and a density of 7.59 g/cc. After milling/mechanical alloying was completed, the powders were annealed. The powders must be annealed after milling in order to relieve stresses incurred from the milling process and to enhance their magnetic properties. Careful attention must be given to the crystallization temperature so that the amorphous structure does not transform to the more stable crystalline atomic structure. The ribbon derived material was annealed at 400°C for 1 hour in vacuum and remained 99% amorphous. The annealing temperature for the powder derived material was determined to be 300°C. The material was consequently annealed for 1 hour in vacuum at this temperature with a final amorphous content between 70-90%. The final particle size distribution for the powder derived material was 2-25 microns and 2-50 microns for the ribbon derived material. Epoxy was chosen as the polymeric matrix material for the metallic glass composites. Epoxy 2000 (Fibre Glast, Brookeville, OH) epoxy resin and hardener system was used for this study. Metallic glass powders were mixed with the resin and hardener in a Flacktek DAC 150 FVZ-K high shear mixer for 1 minute at 1000 rpm and 2 minutes at 2000 rpm. The mixed epoxy and powders were then degassed in a vacuum oven for 15 minutes and cast into silicone molds and cured overnight in a pressure chamber at 70 psi. Samples of neat epoxy, 5 and 15 vol% (24wt%, 52wt%) 85Co-10Si-5Fe, and 5 and 15 vol% (26wt%, 55wt%) 85Co-9Si-4Fe-1Ni-1B were made. The MetGlas derived samples (85Co-9Si-4Fe-1Ni-1B) were given the nomenclature M5 and M15 and the powder derived material (85Co-10Si-5Fe) were given the nomenclature P5 and P15. The samples had the dimensions l = w = 1.5 inches and a nominal thickness of 0.25 inch. The composites were post-cured at 90°C for 4 hours. The P15 and P15 samples had densities of 1.45 g/cc and 1.98 g/cc, respectively, and the M5 and M15 samples had densities of 1.48 g/cc and 2.09 g/cc, respectively. After the samples were machined for testing, the samples had the dimensions shown in Table 1. Examination of the fracture surface showed no signs of porosity." (Bartolucci, 2011, p. 9)

When discussing the results, Bartolucci (2011) addresses the results for the material and states that the results for the absorptive test are:

"Figures 16-20 show the scattering parameters for both C- and X-band samples for each material. Evidence of the inhomogeneity of the samples can be seen in the figures. If the sample was homogeneous the |S11| and |S22| values would be equal. The difference implies that the plane wave is interacting with two different material faces, one being more reflective than the other. The higher the magnitude of |S11| or |S22| signifies a higher reflectivity of that face (recalling that the inclusion rich side is facing Port 1). The homogeneous pure epoxy sample did not display this behavior " (Bartolucci, 2011, p. 21)

and

"Figure 21 through Figure 25 show the measurements for the metal backed experiment. The plots on the left side show the results when the inclusion rich side was placed next to the metal backing and the right side plots display the results when the inclusion deficit side of the material was placed next to the reflection standard. Generally, the inclusion rich side against the reflection standard had higher absorption. This shows that the inclusion rich side is reflecting more of the signal before the wave enters the material. This is due to the higher impedance change from air to the inclusion rich side, " (Bartolucci, 2011, p.23)

After this, the author transitions into the discussion (noting some areas/questions for future research) [pp. 25-26] and also provides a summary (pp. 26-27) with the results being summarized as "the electromagnetic scattering and absorption properties in the upper C-band and X-band spectrum were dependent upon the metallic glass content at the surface. S11 scattering/absorption results showed increased scattering from the inclusion-rich side due to high impedance changes." and "..the electromagnetic scattering and absorption properties in the upper C-band and X-band spectrum were dependent upon the metallic glass content at the surface. S11 scattering/absorption results showed increased scattering from the inclusion-rich side due to high impedance changes." (Bartolucci, 2011)

Resource/Reference Number for Related Personal Research (Non-Commercial) Project- Stealth Technology in the US Military: Past, Present, and Futur". Reference Numbers are not currently alphabetized; they will be added to Zotero for the final work, and subsequently, the current numbering will not reflect the end number assigned to a utilized reference. [REF(0002/0057)].

Project Keywords (Potential): Stealth Technology, IRST, United States Air Force (USAF), B-2 Spirit, Department of Defense (DOD) Next Generation Air Dominance (NGAD), Collaborative Combat Aircraft (CCA), Metamaterials, Nanotechnology, Sensor Technology, EM, SR-71, Strikestar 2025

Reference

Bartolucci, S. (2011). Microwave Absorbing Properties of Metallic Glass/Polymer Composites-ADA586098. https://apps.dtic.mil/sti/pdfs/ADA586098.pdf

Potential Resource Additions as of 08/12/23 (Pending Assessment)

1. Ehrenstein, D. (2023). Physics—Self-Organized Zigzags from Fluid Flo". https://physics.aps.org/articles/v16/138
   

2. Hanks, M. (2023" . DARPA Aims to Develop New Synthetic Quantum Materials That Could Radically Improve Quantum Computing—The Debrie". https://thedebrief.org/darpa-aims-to-develop-new-synthetic-quantum-materials-that-could-radically-improve-quantum-computing/
   

3. Plain, C. (2023, August 8". Impossible Science: MIT Scientists Successfully Demonstrate First-Ever Control over Quantum Randomnes". The Debrief" https://thedebrief.org/impossible-science-mit-scientists-successfully-demonstrate-first-ever-control-over-quantum-randomness/
   

4. Tokyo, U. of. (2023)."Model with an extraordinary glass-forming ability expected to approach the ideal glass state, if it exists." https://phys.org/news/2023-08-extraordinary-glass-forming-ability-approach-ideal.html
   

5. University of California-Santa Barbara."(2023).Hofstadter'sElectron Energy Enigma: Auger-Meitner Effect Unveiled.'https://scitechdaily.com/electron-energy-enigma-auger-meitner-effect-unveiled/
   

6. University of Manchester.'(2023).'Ancient Graphite Reveals a Quantum Surprise: Scientists Discover Butterfly. https://scitechdaily.com/ancient-graphite-reveals-a-quantum-surprise-scientists-discover-hofstadters-butterfly/
   

Notes for PRA and Questions

1. Some information and concepts for Fluid Dynamics. Per the last para. LOC for potential health monitoring applications.

2. Details on initiative and program from DARPA, follow up with project page needed. Areas of note are sensing and RF amplification. LTQ: Utility of RF amplific. in EW, quantum jamming ?....applications for range?...general processing power? Triangulated sensor...relay....likely require prob comp inc, supcon, and advan. in Thermal Field Theory (See: Many-body interactions feel the heat: Introducing thermal field theory (phys.org)), and supplemental q.....do mechanical bodies within a defined space induce changes @ quantum level?

3. Option for probolist. comp. Quantum fluc in vac. Long-term, if progression Q If the ability to control quantum fluctuations within a vacuum becomes more readily available and useable, would a layered structure (if areas of vacuum [integrated into layers-[nano, micro, macro?] and the ability to control quantum fluctuations can impact total energy emitted/observable?) reduce overall visibility or enhance existing?

4. Informative for prjct? , additive to the project? Q: Relation/Comparable to 'Quasicrystals' ?

5. Long-Term Q: Assuming progression, controlled AM process....adap/reac camo? Effic. supportive?

6. Option for probolist. comp. Quantum fluc in vac. Long-term, if progression Qs: If the ability to control quantum fluctuations within a vacuum becomes more readily available and useable, would a layered structure (if areas of vacuum [integrated into layers-[nano, micro, macro?] and the ability to control quantum fluctuations can impact total energy emitted/observable?) reduce overall visibility or enhance existing?