Production of Al Alloys with Kelvin Cells Using the Lost-PLA Technique and Their Mechanical Characterization via Compression Tests

Materials, Journal Year: 2025, Volume and Issue: 18(2), P. 296 - 296

Published: Jan. 10, 2025

The mechanical behavior of AA6082 Kelvin cell foams under compressive tests has been investigated in this work. lost-PLA replication technique, a simple and cheap adopted as the production method. Six Al alloy samples have made successively subjected to order examine response repeatability too. manufactured show good morphology surface finishing, replicating PLA 3D-printed with adequate accuracy. experimental density foam found agreement theoretical one. When static compression, exhibit load-strain diagram characterized by initial linear stage followed two plateaus at increasing load levels. Final densification occurs when there is no more space available for further plastic deformation sharply increases. specific absorbed energy calculated from curves: average measured value was be 2.3 J/cm3, standard deviation six compression 0.3 J/cm3.

Language: Английский

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Bi-material multistable auxetic honeycombs with reusable and enhanced energy-absorbing phases under in-plane crushing

Thin-Walled Structures, Journal Year: 2024, Volume and Issue: 201, P. 111988 - 111988

Published: May 8, 2024

Language: Английский

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Fabrication and Compression Properties of Two-Layered Porous Structure of Different Materials by Direct Printing of Resin Porous Structure on Aluminum Foam Using a 3D Printer

Materials, Journal Year: 2025, Volume and Issue: 18(2), P. 433 - 433

Published: Jan. 17, 2025

The porous structure, in which many pores are intentionally placed inside the material, has excellent impact energy absorption properties. Recent studies have attempted to fabricate multi-layered structures with different mechanical properties within a single structure sample, and of these being elucidated. However, mainly vary densities, pore structures, alloy compositions such as aluminum, for entire sample. Since multi-materials now promoted utilize most suitable material type right place, made materials, combination aluminum resin, expected be required future. In this study, we two-layered samples materials by printing resin using 3D printer on an foam fabricated precursor foaming process. Static compression tests were performed resulting investigate their printed both designed expose surface specimen so that deformation behavior can easily observed. density was varied systematically varying filling rate printed, effect investigated. effectively bonded between two layers anchor effect, is bonding caused penetrating into pores. exhibited robust no evidence separation. It possible those structure. found plateau stress layer controlled about 0.5 MPa 40 MPa, layer. That is, it indicated various densities consisting types allow optimal design used structural materials.

Language: Английский

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A Design Method for Graded Density Components by Polylactic Acid Foaming via Material Extrusion

Lecture notes in mechanical engineering, Journal Year: 2025, Volume and Issue: unknown, P. 75 - 83

Published: Jan. 1, 2025

Language: Английский

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A Co-extrusion Additive Manufacturing Process with Mixer Nozzle to Dynamically Control Blowing Agent Content and Print Functionally Graded Foams

ACS Applied Engineering Materials, Journal Year: 2025, Volume and Issue: 3(3), P. 625 - 635

Published: March 14, 2025

A unique approach to 3D-print functionally graded foams (FGFs) via dynamic control of the blowing agent content is demonstrated. The utilizes a co-extrusion additive manufacturing process equipped with static mixer nozzle (SMN) and thermally expandable microspheres (TEMs) as foaming agent. consists two flow paths, one longer than other, facilitate feeding different filaments. It also layer multiplying elements (LME) for mixing incoming melt streams. first filament was polylactide acid loaded 8.0 wt % TEM (ePLA) be mixed second made neat PLA. filaments at various ratios successfully achieved, resulting in uniform cellular morphologies densities. choice path had significant effect on foam density. When ePLA fed through path, greater degree obtained due residence time. FGF flexural samples, printed this method, demonstrated superior mechanical performance compared their single density solid unfoamed counterparts. results reveal that provides capable method manufacture complex structures programmable profiles specific gravities varying between 0.43 1.21 g cm-3 demand.

Language: Английский

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Orientation-Graded Morphologies in Microcellular Foams through Additive Manufacturing

Industrial & Engineering Chemistry Research, Journal Year: 2024, Volume and Issue: 63(42), P. 17949 - 17960

Published: Oct. 12, 2024

We present experimental findings and modeling insights into the expansion of bubbles within a Newtonian fluid, observed during an advanced process integrating additive manufacturing physical foaming techniques to fabricate complex microcellular foams with orientation-graded morphologies. A sustainable blowing agent (CO2) is solubilized biopolymer (PLA) that 3D-printed through cylindrical nozzle, and, at nozzle outlet, inside polymeric strand due pressure drop or/and temperature rise. The results show that, by engineering gradient high printing velocities, corresponding values Graetz number (i.e., ratio heat diffusion time residence printer hot-end) larger than one, foamed strands have microstructure characterized anisotropic oriented along two different directions. microbubbles center are stretched in extrusion direction, whereas those periphery radially. foam morphology having orientations, smoothly changing cross section, has never been reported before. investigate formation mechanism such simplified numerical simulations. Simulation support rationalize effects on gas suggesting orientations combined effect radial strand.

Language: Английский

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Foam additive manufacturing of thermoplastic polymers: The influence of the process parameters

Journal of Manufacturing Processes, Journal Year: 2024, Volume and Issue: 125, P. 64 - 74

Published: July 17, 2024

The widespread adoption of foam additive manufacturing (FAM) in industries ranging from biomedical to aerospace hinges on the precise control morphology, a capability not fully realized with current technologies. This study explores potential FAM process, employing polylactic acid (PLA) and carbon dioxide (CO2) as blowing agent, finely tune microstructural characteristics foamed materials through controlled manipulation process parameters. By systematically varying pressure time absorption desorption, extrusion temperature, speed, nozzle diameter, we provide detailed analysis their individual collective impact morphology at both macroscopic microscopic levels. Our findings reveal how specific parameter adjustments can significantly influence density, bubble size distribution within strands. These insights only bridge critical knowledge gap optimization but also empower designers engineers across various sectors engineer foams tailored properties for enhanced performance lightweighting, insulation, shock applications. research serves foundational guide advancing practical utility scientific understanding technologies producing next-generation materials.

Language: Английский

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In situ foam 3D printed microcellular multifunctional nanocomposites of thermoplastic polyurethane and carbon nanotube

Carbon, Journal Year: 2024, Volume and Issue: 230, P. 119619 - 119619

Published: Sept. 10, 2024

Language: Английский

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Environmental Impact Assessment of an Integrally 3d Printed, Bio-Based and Biodegradable Sandwich Structure with Functionally Graded Core Based on Pla Foam

Published: Jan. 1, 2024

Language: Английский

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