Design methodology for porous composites with tunable thermal expansion produced by multi-material topology optimization and additive manufacturing

Designing Mechanical Metamaterials with Kirigami‐Inspired, Hierarchical Constructions for Giant Positive and Negative Thermal Expansion

“…Ashby plot of the thermal expansion coefficients versus the filling ratio for the representative mechanical metamaterials reported previously [ 3–7,9–12,54,56,60,61,63,66,70 ] and kirigami‐inspired 2D hierarchical designs proposed in the current work. i) Reproduced with permission.…”

“…Most natural materials expand isotropically upon heating because the kinetic energy of molecules increases their range of motion in non‐parabolic atomic potentials, thereby offering positive thermal expansion coefficients (CTEs), most of which are in the range from ≈1 to 300 ppm K −1 . Recent studies demonstrate that mechanical metamaterials with optimized microstructure architectures can yield unconventional thermal expansion behaviors, such as near‐zero thermal expansion, [ 1–5 ] negative thermal expansion, [ 6–11 ] and thermally induced shear. [ 12 ] These mechanical metamaterials are of increasing interest, because of their potential for use in applications such as high‐precision space optical systems, [ 13,14 ] adaptive connecting components in satellites, [ 15,16 ] flexible MEMS that require excellent thermal stability, [ 17–24 ] battery electrodes with unique thermal expansion, [ 25–29 ] dental fillings, [ 30 ] thermally controlled shape‐changing structures, [ 12,31–48 ] etc.…”

“…Ashby plot of the thermal expansion coefficients of natural materials, [ 11,64 ] NTE materials, [ 50,52,72–77 ] representative mechanical metamaterials reported previously (i.e., planar lattice structures, [ 3–5,11,54,56,60,61,63,66 ] topology optimized structures, [ 9,10 ] and chiral metamaterials [ 6,7,12 ] ), and kirigami‐inspired 2D hierarchical designs proposed in the previous [ 70 ] and current work. i) Reproduced with permission.…”

“…vi) Reproduced with permission. [ 9 ] Copyright 2017, Elsevier Ltd. vii) Reproduced under the terms of the CC‐BY Creative Commons Attribution 3.0 Unported license (https://creativecommons.org/licenses/by/3.0). [ 10 ] Copyright 2015, The Authors, published by American Institute of Physics.…”

Current and future trends in topology optimization for additive manufacturing

“…Clausen et al realized control of Poisson's ratio even in large deformation region considering geometrical nonlinearity [117]. Utilizing multi-material photopolymer AM, Takezawa et al realized negative thermal expansion [118] and large positive thermal expansion [119]. The study on basic physical properties of thermal conductivity, stiffness, and strength are still active even recently [120][121][122][123][124].…”