4D打印复合软材料力学性能预测研究进展

赵先锋; 汤朋飞; 史红艳

doi:10.13801/j.cnki.fhclxb.20210106.001

4D打印复合软材料力学性能预测研究进展

doi: 10.13801/j.cnki.fhclxb.20210106.001

贵州大学　机械工程学院，贵阳 550025

基金项目: 国家自然科学基金 (51765009)

详细信息

通讯作者:
史红艳，博士，讲师，研究方向为3D/4D打印、切削机制等　E-mail：historyard@126.com

中图分类号: TB332
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- 被引次数: 0
出版历程
- 收稿日期: 2020-11-05
- 录用日期: 2021-01-04
- 网络出版日期: 2021-01-06
- 刊出日期: 2021-06-23

Research progress on prediction of mechanical properties of 4D printing soft composite

School of Mechanical Engineering, Guizhou University, Guiyang 550025, China

摘要

摘要: 4D打印是一门新兴的制造技术，所打印结构的形状、属性或功能在外部环境的刺激下会随着时间的推移而变化。智能软物质材料由于变形大，激励响应机制多，响应速度快等特点被广泛使用于4D打印中，尤其是形状记忆水凝胶和形状记忆聚合物。目前对复合软材料的刚度和弯曲形状的控制是4D打印在应用上的两个难题，建立4D打印复合结构的等效模量和曲率预测模型对复合软材料的力学性能的设计具有指导意义。本文对现有的4D打印复合结构的等效模量及弯曲曲率模型进行了概述，首先介绍了4D打印结构在静态和动态下的弹性模量预测模型，然后，重点综述了Stoney理论，Timoshenko理论和复合材料力学在复合软材料弯曲曲率建模上的应用。最后探讨了现有4D打印复合软材料力学预测模型存在的问题及主要发展的方向。
- 4D打印 /
- 制造技术 /
- 复合软材料 /
- 等效模量 /
- 曲率 /
- 预测模型
Abstract: 4D printing is an emerging manufacturing technology, the shape, property, or functionality of the printed structure will change with time under the stimulation of external environment. Smart soft matter is widely used in 4D printing due to its large deformation, multiple excitation response mechanisms and fast response speed, especially shape memory hydrogels and shape memory polymers. At present, the control of rigidity and bending shape of soft composite is two difficult problems in the application of 4D printing, and the establishment of equivalent modulus and curvature prediction models has guiding significance for the design of mechanical properties of 4D printed composite structures. This article gave an overview of the equivalent modulus and bending curvature models of the existing 4D printed composite structures, the elastic modulus prediction models of 4D printed structures under static and dynamic conditions were introduced. Then, the application of Stoney theory, Timoshenko theory and composite material mechanics in flexural curvature modeling of soft composite was emphatically reviewed. In the end, the existing problems of the existing 4D printing soft composite mechanics prediction model and the main development direction were discussed.
- 4D printing /
- manufacturing technology /
- soft composite /
- equivalent modulus /
- curvature /
- prediction model

HTML全文

图 1 五种常见软物质3D打印方法^[18,24]

Figure 1. Five common 3D printing methods for soft matter^[18,24]

SLA—Stereolithographyl; FDM—Fused deposition modelling; DIW—Direct ink writing; DLP—Digital light processing

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图 2 坐标定义^[35]

Figure 2. Coordinate definition^[35] ((a) Coordinate transformation relationship; (b) Z coordinate of printing structure)

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图 3 熔融沉积成型(FDM)打印丝实际宽度模型和其受力情况^[39]

Figure 3. Fused deposition modelling (FDM) filament actual width model and its stress^[39]

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图 4 三角形单元和六边形单元填充结构参数^[35]

Figure 4. Filling structure parameters of triangular elements and hexagonal elements^[35] ((a) Loading in the [0] direction; (b) Loading in the [90] direction; (c) Optical image and geometry of the cross section of printed multilayer structure; (d) Hexagonal element of a two-dimensional model of printed structure)

σ_x—Stress in x direction; σ_y—Stress in y direction; δ₁—Deflection of beam AB; δ₂—Axial deformation of beam AB; δ₃—Axial deformation of beam BC; P_B1—Force applied on beam AB; P_B2—Force applied on beam BC

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图 5 3×4多单元细胞壁结构^[45-46]

Figure 5. 3×4 multi-unit cell wall structure^[45-46] ((a) Programming and recovery process; (b) Schematic diagram of parameters)

x—Direction of applied load; ∆L_prog—Tensile strain

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图 6 三点弯曲试验简化图

Figure 6. Simplified diagram of three-point bending test

F—Force applied to the center of the specimen; L—Curved span

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图 7 广义Maxwell-Wiechert模型^[35]

Figure 7. Generalized Maxwell-Wiechert model^[35]

E_∞—Modulus after complete relaxation; E_i—Modulus of the i th relaxation mode; η_i—Viscosity of the i th relaxation mode

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图 8 4D打印结构从永久形状重新编程为多种不同配置的能力演示^[54]

Figure 8. Demonstration of the ability of 4D printed structures to be reprogrammed from permanent shapes to multiple different configurations^[54]

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图 9 多分支模型的一维流变表征^[54]

Figure 9. 1D rheological representation of the multi-branch mode^[54]

E_eq—Elastic modulus of equilibrium branch; E_i—Elastic modulus of each nonequilibrium branch; η_i—Viscosity of each nonequilibrium branch

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图 10 黏弹性模型描述的热响应SMP变形过程^[56]

Figure 10. Thermal SMP deformation process described by viscoelastic model^[56]

E_f, E_e—Elastic modulus of springs f and e; η—Viscosity

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图 11 双层生物杂交薄膜^[59]

Figure 11. Double-layer biological hybrid film^[59]

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图 12 自折叠聚合物折纸的制备^[60]

Figure 12. Fabrication of self-folding polymer origami^[60] ((a)-(b) Origami schematic diagram; (c) Landlet flying bird; (d) Polymer layer of film)

W_m—Top hinge width; W_v—Bottom hinge width; h_P—Polymer film thickness; h_N—Hydrogel thickness

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图 13 光驱动结构的编程过程^[61]

Figure 13. Programming process of the optical drive structure designed^[61] ((a) Schematic for the multicolor SMP structure; (b) Side view of the structure; (c) Programming and bending behavior)

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图 14 编程应变与弯曲角度之间的关系^[61]

Figure 14. Relationship between programming strain and bending angle^[61]

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图 15 不同厚度但相同长度的双层结构弯曲曲率变化^[62]

Figure 15. Bending curvature of double-layer structure with different thickness but same length^[62]

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图 16 不同双层厚度比溶胀造成的弯曲^[63]

Figure 16. Bending caused by swelling with different double-layer thickness ratios^[63]

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图 17 用4D打印设计仿生智能花^[64]

Figure 17. Design bionic smart flowers with 4D printing^[64] ((a) Anisotropic expansion; (b) Shape under different curvatures; (c) Deformation of double-layer complex structure)

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图 18 由纤维收缩而造成的弯曲^[67]

Figure 18. Bending caused by fiber shrinkage^[67]

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图 19 叶片主脉与侧脉之间的角度图解^[70]

Figure 19. Diagram of the angle between the main vein and the lateral vein of the leaf^[70]

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图 20 不对称层合板冷却固化后引发的变形^[73]

Figure 20. Deformation of unsymmetrical laminates after heat bonding and cooling^[73]

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图 21 嵌入连续纤维复合材料可编程变形^[75]

Figure 21. Programmable deformation of embedded continuous fiber composite material^[75] ((a) Printing process; ((b)-(c)) Cross-section of the double-layer fiber; ((d)-(f)) Relationship between the curvature and the fiber bundle)

H_C—Fiber thickness; H_P—Resin thickness; b—Fiber width; B—Width between fiber bundles; k_a, k_b—Curvature vector of single fiber surface; k₁—Principal curvature vector

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图 22 连续纤维复合材料的横截面^[75]

Figure 22. Cross section of continuous fiber composite^[75]

r—Radius of curvature

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图 23 双层结构的高度(h)和宽度(w)^[76]

Figure 23. Height (h) and width (w) of the double-layer structure^[76]

w_T—Length of elastomer; h_T—Thickness of elastomer; w_e—Length of transition material; h_e—Thickness of transition material; n_aT—Neutral axis of elastomer; n_ae—Neutral axis of transition material

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图 24 材料体素化建模^[80]

Figure 24. Modeling of material voxelization^[80]

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