![]() ![]() Additional to the manufacturing challenges of the 3D lattice structure includes their fabrication speed, topology design, large data feed, and shape conformity, which are some non-trivial issues. Fabrication imperfections, namely topological (variations in nodal connectivity and missing strut) 5, 6, and dimensional (variations in cellular dimensions) 7, 8, 9, are widespread challenges even in mesoscale (couple mm) unit cell size lattice, which makes the lattice structures often unattainable. Superior and predictable performance in lattice structure requires design and manufacturing perfections (i.e., unit cell parameters, connected nodes, porosity, etc.). Higher nodal connectivity (> 6) in 3D lattice is needed for structural rigidity 3 (i.e., stiff and strong structures), while compliant and consistent deformation may result from bending-dominated structures 4. Assembling these unit cells forms a complex structural network 1 and follows Maxwell’s criterion 2 which helps to determine the strut-based topologies to equilibrate external force and moment. The open cell structures consist of a number of repetitive connected members or tessellated unit cells which are constructed with elements/struts 1 and connected through point contact, often defined as a node. Lattice structures are compelling candidates for the development of a wide range of engineering structures, i.e., boat hull, propellers, airplane wings, fuselage, biomedical implants and prosthetics, automobile chassis, heat exchangers, shelters, and bridge structures, etc. ![]() ![]() The strength and elastic modulus of all the fabricated samples decreases with the increase in cell size, which is consistent with the traditional wisdom. The lattice structure shows comparable strength even with smaller relative density (< 10%). 3D metal lattice structures are constructed, and their mechanical properties are investigated. We found 40% solid loading with the liquid carrier system provides sufficient solid particles transfer at dipping and join the lattice node using transient liquid phase bonding (TLP). Liquid Carrier Systems (LCS) are designed considering their rheological behavior. Both liquid state (epoxy) and solid-state (inorganic particles) joining agents are considered for polymer–metal and metal–metal bonding, respectively. This paper is investigating the joining of nodes in a loose lattice structure by delivering materials through the dipping process. However, joining their nodes are challenging and an important problem to solve. A multi-layer, periodic, and aperiodic lattice structure can be manufactured with a continuous thin rod by bending it with a repetitive pattern. This leads to a decrease in reflectivity, which depends on the metal's characteristics.In this paper, a new possibility of fabricating a metal lattice structure with a continuous rod is demonstrated. ![]() However, in higher frequencies, deviations of Drude`s approach start to appear, because bound electrons of the metal start to respond to the incidence of light, instead of just valence band electrons response. It was observed that, at higher wavelengths (lower frequencies), the optical constants of metals are similar to the values of Drude`s function, where the complex refractive index is much smaller then the damping constant, or extinction coefficient. This conclusion was derived by Drude and confirmed experimentally by Hagens-Ruben. ![]()
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