Characterization, Design and Modeling of Novel Shape Memory Composites

这笔赠款提供财政资金，用于设计、制造和模拟结构稳定的强形状记忆复合材料的行为，这些复合材料可以在温度和/或磁场下恢复大变形。新型形状记忆复合材料将由(常规的和磁性的)形状记忆合金和形状记忆聚合物组成。通过系统研究预应变、混合比、表面光洁度、体积比、合金尺寸和形状对形状记忆复合材料的强度、塑性、回复应力和应变、界面强度、阻尼和刚度等性能的影响，可以更深入地了解形状记忆复合材料的温度、应力和磁场相关特性以及可逆驱动机制。此外，还将建立基于细观力学的分析模型来解释和预测形状记忆复合材料的行为，并通过已有的实验结果对其进行标定。如果成功，将会制造出具有大的可逆驱动的新型复合材料，其功能特性如刚度和阻尼可随温度和磁场的变化而可调。制备的复合材料可以作为高耐久、轻质、高强度、低成本和功能可调的复合材料，从而在执行器应用中产生更有效的系统和机构。它们可以利用i)自我感知能力来感知环境条件(例如温度、湿度)的变化并相应地调整其行为；ii)具有可用于支架和药物输送系统的可逆驱动能力的高强度；iii)用于隔振的依赖于温度和磁场的减振特性；iv)用于结构自我修复的力产生能力。鉴于拟议研究的跨学科性质，该项目将对新兴智能材料领域的研究生/本科生、K-12学生、高中教师和广大公众的科学教育作出重大贡献。

This grant provides financial funding to design, fabricate and model the behavior of structurally stable and strong shape memory composites that could recover large deformations with temperature and/or magnetic field. Novel shape memory composites will be composed of (conventional and magnetic) shape memory alloys and shape memory polymers. A deeper understanding of temperature, stress and magnetic field-dependent properties and reversible actuation mechanisms of shape memory composites will be attained by systematic investigations of the effects of pre-straining, mixture ratio, surface finish, volume ratio, size and shape of alloys on the strength, ductility, recovery stress and strain, interfacial strength, damping and stiffness properties of shape memory composites. Moreover, a micromechanics-based analytical model will be founded to explain and predict the behavior of shape memory composites and then calibrated through the achieved experimental findings. If successful, novel composites that could demonstrate large reversible actuation with tunable functional properties such as stiffness and damping as functions of temperature and magnetic field will be fabricated. Fabricated composites can be employed as high endurance, lightweight, higher strength, low cost and functionally tunable composites to result in more efficient systems and mechanisms in actuator applications. They can utilize their i) self-sensing ability to sense the changes in environmental conditions (e.g. temperature, humidity) and adapt their behavior accordingly; ii) high strength with reversible actuation capability to be used as stents and drug delivery systems; iii) temperature and magnetic field dependent damping properties for vibration isolation, iv) force generation capability for self-healing in structures. Given the interdisciplinary nature of the proposed research, this project will contribute significantly to the scientific education of graduate/undergraduate university students, K-12 students, high school teachers and the public at large in the emerging field of intelligent materials.