Unraveling the ultrahigh modulus of resilience of Core-Shell SU-8 nanocomposite nanopillars fabricated by vapor-phase infiltration
Unraveling the ultrahigh modulus of resilience of Core-Shell SU-8 nanocomposite nanopillars fabricated by vapor-phase infiltration
复制标题
揭示气相渗透制备的核壳SU-8纳米复合材料纳米柱的超高回弹性模量
DOI：
10.1016/j.matdes.2023.111770
复制
发表时间：
2023
影响因子：
8.4
通讯作者：
Lee, Seok-Woo
中科院分区：
文献类型：
--
作者：
Li, Zhongyuan;He, Jinlong;Subramanian, Ashwanth;Tiwale, Nikhil;Dusoe, Keith J.;Nam, Chang-Yong;Li, Ying;Lee, Seok-Woo
弹性模量，可以存储在弹性变形固体中的最大应变能密度，是用于开发机器人、软电子面板和微/纳米机电致动器中的人工肌肉的重要机械特性。在这项研究中，核-壳SU-8纳米复合材料通过气相渗透纳米级非晶氧化铝到SU-8纳米柱，并进行透射电子显微镜，纳米力学测试，分析建模和原子模拟，以获得一个基本的洞察弹性模量远高于大多数高强度材料。这项研究表明，弹性模量的结果从：低纵横比的无定形氧化铝纳米颗粒;颗粒尺寸厚于自由体积尺寸;和薄的氧化铝纳米颗粒内的互连链接。这些独特的微观结构特征产生了低的比杨氏模量（E）（4 MPa/（kg/m3））和高的比屈服强度（σ y）（0.2MPa/（kg/m3））的不寻常组合，导致比回弹模量（5.21± 0.39kJ/kg（σ y2/（2 E）比具有类似屈服强度的材料高约10倍。这项研究表明，气相渗透是一个很好的制造方法，以生产聚合物纳米复合材料，可以吸收和释放大量的弹性应变能。
Modulus of resilience, the maximum strain energy density that can be stored in an elastically deformed solid, is an important mechanical property for developing artificial muscles in robotics, soft electronics panels, and micro-/nano-electromechanical actuators. In this study, core–shell SU-8 nanocomposites were fabricated via vapor-phase infiltration of nanoscale amorphous aluminum oxides into SU-8 nanopillars and performed transmission electron microscopy, nanomechanical testing, analytical modeling, and atomistic simulations to gain a fundamental insight into the ultrahigh modulus of resilience much higher than that of most high-strength materials. This study shows that the ultrahigh modulus of resilience results from: the low aspect ratio of amorphous aluminum oxide nano-particulates; the particulate size thicker than the free volume size; and the thin aluminum oxide interconnecting links within nano-particulates. These unique microstructural features produce the unusual combination of low specific Young’s modulus (E), 4 MPa/(kg/m 3), and high specific yield strength (σ y), 0.2 MPa/(kg/m 3), leading to the specific modulus of resilience, 5.21±0.39 kJ/kg (σ y 2/(2 E)) about ten times higher than materials with the similar yield strength. This study demonstrates that vapor-phase infiltration is an excellent fabrication method to produce a polymer nanocomposite that can absorb and release a large amount of elastic strain energy.