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This work presents a systematic study of the relationship between structural stochasticity and the crush energy absorption capability of lattice structures, with controlled stiffness and weight. We develop a Voronoi tessellation-based approach to generate multiple series of lattice structures with either equal weight or equal stiffness, smoothly transitioning from periodic to stochastic configurations for crush energy absorption analysis. The generated lattice series fall into two categories, originating from periodic honeycomb and diamond lattice structures. A new stochasticity metric is proposed for quantifying the structural stochasticity and is compared with the state-of-the-art stochasticity metrics to ensure a consistent measurement. The crush energy absorption properties are obtained using explicit finite element analysis and we observe similar stochasticity-property trends in simulations using both elastic-plastic and hyperelastic materials. We report a new observation that an intermediate level of stochasticity between periodic and high randomness leads to the best crush energy absorption performance. Our analysis reveals that this optimal performance arises from enhanced activation of deformation hinges, promoting efficient energy absorption. 

This work presents a systematic study of the relationship between structural stochasticity and the crush energy absorption capability of lattice structures, with controlled stiffness and weight. We develop a Voronoi tessellation-based approach to generate multiple series of lattice structures with either equal weight or equal stiffness, smoothly transitioning from periodic to stochastic configurations for crush energy absorption analysis. The generated lattice series fall into two categories, originating from periodic honeycomb and diamond lattice structures. A new stochasticity metric is proposed for quantifying the structural stochasticity and is compared with the state-of-the-art stochasticity metrics to ensure a consistent measurement. The crush energy absorption properties are obtained using explicit finite element analysis and we observe similar stochasticity-property trends in simulations using both elastic-plastic and hyperelastic materials. We report a new observation that an intermediate level of stochasticity between periodic and high randomness leads to the best crush energy absorption performance. Our analysis reveals that this optimal performance arises from enhanced activation of deformation hinges, promoting efficient energy absorption. 

Elastocaloric polymers, whose performance typically relies on phase transformation between amorphous chains and crystalline domains, offer a promising alternative to traditional refrigeration technologies. While engineering polymer‐network architecture has shown the potential to boost elastocaloric performance, the role of topological defects remains unexplored despite their prevalence in real polymers. This study reports a defect‐engineering approach in end‐linked star polymers (ELSPs) that enables an adiabatic temperature change of up to 8.14 ± 1.76 °C at an ambient temperature above 65 °C, showing an enhancement of 39% compared to ELSPs with negligible defects. This defect‐regulated solid‐state cooling is attributed to two competing effects of dangling‐chain defects on strain‐induced crystallization (SIC) and temperature‐induced crystallization (TIC), synergistically regulating the adiabatic temperature change. Specifically, increasing dangling‐chain defects monotonically lowers ELSPs’ mechanical performance at high temperatures due to suppressed SIC, but nonmonotonically impacts the mechanical performance at low temperatures due to the competition between suppressed SIC and enhanced TIC.