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Tunable energy absorption achieved through grading of lattice structures shows high potential to be used in lightweight cellular cores for energy absorbing structures. This study investigates structurally graded and multi-material lattices consisting of plate-based octet unit cells, under quasi-static compression, to assess their energy absorption ability. Variations in the structure and material compositions of the plate-lattice structures are achieved through changing the plate thickness and through changing the filament material along the lattice in the direction of applied compressive force. The compressive stress–strain behavior reveals a near 10% increase of specific energy absorption (SEA) in the plate thickness graded designs at higher strain compared to the baseline octet lattices. The multi-material arrangements significantly modified onset location of the structure collapse. Finite element models of the structures were developed, and good agreements with experimental results were observed. Effects of varying each of the unit cell geometric parameters were analyzed, and the high sensitivity to the plate inclination angle, which resulted in greater changes to the maximum stress values and control of the overall SEA, was identified. The results demonstrate the capacity to adapt the octet lattice structure design through additive manufacturing to better suit the expected load and application.

Nanocomposite film heaters are promising for out-of-oven (OoO) and energy-efficient curing of fiber-reinforced polymer composites. However, the current techniques for manufacturing nanocomposite film heaters are intensive in terms of time and energy and require expensive resources. In this work, we present a facile and rapid approach for preparation of nanocomposite film heaters with excellent heat generation properties based on a frontally polymerizable resin system. This approach enables rapid fabrication of nanocomposite films within a few minutes and without the need for using expensive equipment, making it suitable for mass production of nanocomposite film heaters. Various characterization techniques are used to determine the morphology, composition, and mechanical properties of nanocomposite films. The electrothermal performance of nanocomposite film heaters are then evaluated under various conditions. Nanostructured heaters exhibit excellent Joule heating properties, where temperatures as high as ∼132°C can be reached within only 2 min using a low input power density of ∼2 W cm−2. Finally, a nanocomposite film heater is used for OoO curing of a small composite panel with minimal energy consumption. Using this approach, 0.1 MJ of energy is consumed during the 4-h cure cycle of a commercial prepreg system, which would otherwise require at least 40.5 MJ of energy to cure using a convection oven.