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Ryan S.M.,Johns Hopkins University | Szyniszewski S.,University of Surrey | Ha S.,Korea Maritime and Ocean University | Xiao R.,Johns Hopkins University | And 5 more authors.
Scripta Materialia | Year: 2015

Cu and NiCr metallic lattice materials of two different micro-architectures were manufactured with a 3D weaving process. Dynamic mechanical analysis experiments demonstrated that the damping properties of these materials are much greater than their bulk counterparts and were found to have damping loss coefficients comparable to polymers, but with much higher maximum use temperatures. The magnitude of the damping phenomenon is characterized experimentally, and the importance of Coulomb (frictional) damping and inertial damping are investigated using a finite element model. © 2015 Acta Materialia Inc.

Misencik S.A.,SAERTEX United States LLC
SPE Automotive and Composites Divisions - 12th Annual Automotive Composites Conference and Exhibition 2012, ACCE 2012: Unleashing the Power of Design | Year: 2012

Esthetically pleasing: No geometry constraints as imposed by metal forming techniques Scratch & dent resistent: Higher ultimate tensile elongation than metals Traditional repair techniques (marine, automotive) Rust & rot resistant: Non-corrosive, no metal Impervious to chemicals Lighter weight than metal: Self-supporting bus body without chassis Designed to meet all transport rigors: Some models currently travelling over 1,100,000 miles Can be packaged with all many types of drive systems: Diesel, bio-diesel, CNG, LNG, hybrid electric drive, fuel cell...

Zhao L.,Johns Hopkins University | Ryan S.M.,Johns Hopkins University | Ortega J.K.,Johns Hopkins University | Ha S.,Johns Hopkins University | And 5 more authors.
International Journal of Heat and Mass Transfer | Year: 2016

Stochastic metallic foams and periodic porous media have been used extensively in heat transfer applications. A relatively new cellular material, 3D woven Cu lattices, show potential for increased thermal performance, due to their high specific surface areas, high thermal conductivity and regular micro-pore distributions. This work investigates the performance of these lattices in both a "standard" and a topology "optimized" architecture using three flow patterns (axial, focused bifurcated and full bifurcated) and two working coolants (water and air). We characterize and compare three performance metrics: pressure drop, average surface temperature and temperature uniformity for the various lattices, flow patterns, and coolants. The optimized weave shows lower pressure drops but higher average surface temperatures and higher temperature variations compared to the standard weave for all flow patterns and both coolants. The bifurcated flow patterns demonstrate lower pressure drops and lower temperature variations but higher average surface temperatures compared to the axial flow pattern for the two weaves and coolants. We also compare the fluidic and thermal performance of the weaves to other common heat dissipation media using the axial flow pattern and both coolants by plotting friction factors, Nusselt numbers and thermal efficiencies as a function of Reynolds numbers that range from 3 to 125. The standard and optimized weaves exhibit relatively high values in flow resistance and heat transfer, and similar values in thermal efficiency compared to other heat exchangers when using water or air. In addition, the weaves provide excellent temperature uniformity in the bifurcated flow patterns, suggesting they are great candidates for applications requiring both high heat removal and uniform temperature distributions such as the cooling of high power laser diodes. © 2016 Elsevier Ltd. All Rights Reserver.

Erdeniz D.,Northwestern University | Sharp K.W.,SAERTEX United States LLC | Dunand D.C.,Northwestern University
Scripta Materialia | Year: 2015

Architectured Ni-based superalloy scaffolds were fabricated by three-dimensional weaving of ductile Ni-20Cr (wt.%) wires followed by gas-phase alloying with aluminum and titanium via pack cementation. Bonding of neighboring wires occurs at necks that are formed by solid-state diffusion or by formation of a transient-liquid phase. Three-point bending tests of the superalloy weaves, after homogenization and aging to achieve a γ/γ′ structure, show that, as bonding between wires increases, the materials withstand higher stresses and strains before onset of damage. © 2015 Acta Materialia Inc.

Bakker S.,SAERTEX GmbH and Co. KG | Sharp K.,SAERTEX United States LLC
CAMX 2014 - Composites and Advanced Materials Expo: Combined Strength. Unsurpassed Innovation. | Year: 2014

A cost-efficient infusion solution for carbon fiber spar caps for wind turbine blades has been developed. It is based on a carbon fabric with a more than 5 times improved permeability, allowing the infusion of a 90-layer stack of 620 gsm carbon fiber UD with a normal viscosity resin in 90-150 min. A complete set of mechanical data has been tested, lab scale trials performed and a full scale spar cap of a 75 m. wind turbine blade has been successfully produced. Another approach for reducing labor and layup costs in thick composite laminate schedules is to use thick 3D fabrics. Reinforcement fibers, such as E-glass, S-glass, carbon or a hybrid of these, alternating in the 0 and 90 degree directions are bound by fibers traversing the through thickness direction (Z) in a manner that leaves the in-plane fibers with no crimp. The lack of crimp provides increased strength compared to multiple layers of traditionally woven fabrics, while the Z yarns suppress delamination. 3D fabric thicknesses of greater than 50 mm are possible. Open flow paths in the Z direction and the highly regular arrangement of in-plane yarns lead to high infusion speeds, even of these thick fabrics.

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