3D Multiscale Modelling and Characterisation of the Coupled Electromechanical Behaviour of Novel Smart Piezoelectric Nanocomposites

新型智能压电纳米复合材料耦合机电行为的 3D 多尺度建模和表征

基本信息

批准号：
RGPIN-2018-03804
负责人：
Meguid, Shaker
金额：
$ 13.26万
依托单位：
University of Toronto
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2022
资助国家：
加拿大
起止时间：
2022-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=759673
关键词：
3D Multiscale Modelling Characterisation Coupled

项目摘要

BACKGROUND: The aims of my newly proposed research program are to generate new knowledge to accurately model, characterise and develop the next generation of lightweight smart piezoelectric nanocomposites (SPNCs) for use as sensors, actuators and energy harvesters, with greater understanding of the fundamental parameters that govern their electromechanical behaviour. The new SPNCs are fabricated using preferentially aligned array of nanowires (NWs) with finite interspacing and encased by nanoscopic surface electrodes in an epoxy matrix. Due to their outstanding electromechanical properties, Zinc Oxide and Gallium Nitride NWs are selected. The piezoelectric coefficients define the electromechanical behaviour of NWs and SPNCs; beyond the small field condition, these coefficients are temperature dependent. RESEARCH PROGRAM: The long-term aims are to generate new knowledge leading to new SPNCs' designs and analysis tools, requiring the following short term objectives:1. Determine the effective mechanical properties and the direct piezoelectric coefficients of a homogenised sensor fiber for the direct piezoelectric effect by applying mechanical strain at constant electric field using novel hybrid molecular dynamics (MD)-density functional theory (DFT) to a NW surrounded by an epoxy matrix. 2. Compute the effective mechanical properties and the converse piezoelectric coefficients of a homogenised actuator fiber for the converse piezoelectric effect using DFT-MD. 3. Determine the bulk electromechanical properties of SPNCs by scaling up a network of the effective sensor fibers developed in Objective 1 using 3D hierarchical multiscale strategy. 4. Compute the bulk electromechanical properties of SPNC by scaling up a network of the effective actuator fibers developed in Objective 2 using modified micromechanics and homogenization schemes and a new network recognition strategy. 5. Conduct extensive experimental work that involves the measurements of the parameters that govern the behaviour of NWs and SPNCs, which will guide the respective atomistic and continuum models and validate their predictions. The largely unknown role of doping, defects, depolarisation and temperature of these wurtzite nanostructures will be examined in Objectives 1-5.SIGNIFICANCE: SPNCs are envisioned to be the building blocks of next generation civil and military applications, characterised by adaptability, multifunctionality and autonomy for sensing, actuating, and energy harvesting. The research will pioneer a technique to characterise the effect of thermo-electro-mechanical loading on the piezoelectric coefficients, overcome the numerous limitations of monolithic piezoceramics, develop highly versatile smart nanocomposites, address anomalies and deficiencies in existing literature, train 66 HQP, and facilitate technology transfer to Canadian industry and military.

背景：我新提出的研究计划的目的是产生新知识，以准确建模、表征和开发用作传感器、执行器和能量收集器的下一代轻质智能压电纳米复合材料（SPNC），同时更好地了解基本参数控制它们的机电行为。新的SPNC是使用具有有限间距的优先排列的纳米线（NW）阵列制造的，并被环氧树脂基质中的纳米级表面电极包围。由于氧化锌和氮化镓纳米线具有出色的机电性能，因此被选中。压电系数定义了 NW 和 SPNC 的机电行为；除了小磁场条件外，这些系数与温度有关。研究计划：长期目标是产生新知识，从而产生新的 SPNC 设计和分析工具，需要实现以下短期目标：1．通过使用新颖的混合分子动力学 (MD)-密度泛函理论 (DFT) 在恒定电场下对环氧树脂包围的 NW 施加机械应变，确定均匀传感器纤维的有效机械性能和直接压电系数，以实现直接压电效应矩阵。 2. 使用 DFT-MD 计算逆压电效应的均质致动器纤维的有效机械性能和逆压电系数。 3. 通过使用 3D 分层多尺度策略放大目标 1 中开发的有效传感器纤维网络，确定 SPNC 的整体机电特性。 4. 使用改进的微力学和均质化方案以及新的网络识别策略，通过扩大目标 2 中开发的有效致动器纤维网络来计算 SPNC 的整体机电特性。 5. 进行广泛的实验工作，包括测量控制 NW 和 SPNC 行为的参数，这将指导各自的原子模型和连续模型并验证其预测。这些纤锌矿纳米结构的掺杂、缺陷、去极化和温度的作用很大程度上未知，将在目标 1-5 中进行研究。意义：SPNC 被设想成为下一代民用和军事应用的基石，其特点是适应性、多功能性和自主性用于传感、驱动和能量收集。该研究将开创一种技术来表征热机电负载对压电系数的影响，克服单片压电陶瓷的众多限制，开发高度通用的智能纳米复合材料，解决现有文献中的异常和缺陷，训练 66 HQP，并促进向加拿大工业和军事领域转让技术。