Inverse design and additive manufacturing of shape-morphing structures based on functionally graded composites
Inverse design and additive manufacturing of shape-morphing structures based on functionally graded composites
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DOI：
10.1016/j.jmps.2023.105382
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发表时间：
2023-07
影响因子：
5.3
通讯作者：
H. Kansara;Mingchao Liu;Yinfeng He;Wei Tan
中科院分区：
文献类型：
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作者：
H. Kansara;Mingchao Liu;Yinfeng He;Wei Tan
形状变形结构具有将形状从一种状态改变到另一种状态的能力，因此具有广泛的应用潜力。变形的典型范例是从初始的二维(2D)平面构型转变为三维(3D)目标结构。这些结构的一种流行的制造方法涉及在薄板材料(即Kirigami)的特定位置编程切割，在施加外部机械载荷时形成所需的3D形状。通过采用非线性波束方程，提出了一种确定实现轴对称三维目标形状所需的二维切割图案的逆向设计策略。具体地说，定制弯曲刚度的局部变化是关键要求。本文提出了一种通过在功能梯度复合材料(FGCS)中引入分布模量来修正弯曲刚度的新的逆向设计策略。为了制作基于FGC的形状变形结构，我们使用了一台多材料3D打印机来打印具有体素状构建块的梯度复合材料。根据细观力学模型，可以通过混合物规则控制每个横截面的纵向弹性模数，从而匹配所需的弹性条上的模数分布。根据所提出的框架，在数值模拟和实验中都得到了不同高斯曲率的各种结构。变形结构的测量形状与目标的形状之间达到了很好的一致性。此外，还对不同高宽比的FGC基半椭球变形结构的压缩刚度和压缩比能量吸收进行了数值分析和实验验证。通过系统的数值模拟，我们还论证了模数梯度形状变形复合材料的多功能性。例如，它们能够融合两种不同材料的显著优势，即一种具有高导热(但低电性)导电性，另一种则相反，以在由FGCS制造的单一结构中实现综合有效的性能。这种新的逆向设计框架提供了一个机会，通过利用模数分级复合材料来创建形状变形结构，这种复合材料可以应用于涉及多种物理环境的各种应用中。此外，这一框架强调了该方法的多功能性，使之能够在地方一级精确控制材料属性。
Shape-morphing structures possess the ability to change their shapes from one state to another, and therefore, offer great potential for a broad range of applications. A typical paradigm of morphing is transforming from an initial two-dimensional (2D) flat configuration into a three-dimensional (3D) target structure. One popular fabrication method for these structures involves programming cuts in specific locations of a thin sheet material (i.e. kirigami), forming a desired 3D shape upon application of external mechanical load. By adopting the non-linear beam equation, an inverse design strategy has been proposed to determine the 2D cutting patterns required to achieve an axisymmetric 3D target shape. Specifically, tailoring the localised variation of bending stiffness is the key requirement. In this paper, a novel inverse design strategy is proposed by modifying the bending stiffness via introducing distributed modulus in functionally graded composites (FGCs). To fabricate the FGC-based shape-morphing structures, we use a multi-material 3D printer to print graded composites with voxel-like building blocks. The longitudinal modulus of each cross-sectional slice can be controlled through the rule of mixtures according to the micro-mechanics model, hence matching the required modulus distribution along the elastic strip. Following the proposed framework, a diverse range of structures is obtained with different Gaussian curvatures in both numerical simulations and experiments. A very good agreement is achieved between the measured shapes of morphed structures and the targets. In addition, the compressive rigidity and specific energy absorption during compression of FGC-based hemi-ellipsoidal morphing structures with various aspect ratios were also examined numerically and validated against experiments. By conducting systematical numerical simulations, we also demonstrate the multifunctionality of the modulus-graded shape-morphing composites. For example, they are capable of blending the distinct advantages of two different materials, i.e. one with high thermal (but low electrical) conductivity, and the other is the other way around, to achieve combined effective properties in a single structure made by FGCs. This new inverse design framework provides an opportunity to create shape-morphing structures by utilising modulus-graded composite materials, which can be employed in a variety of applications involving multi-physical environments. Furthermore, this framework underscores the versatility of the approach, enabling precise control over material properties at a local level.