Stress and Interface Engineering of Functional Materials

功能材料的应力与界面工程

• 批准号: RGPIN-2015-04185
• 负责人: Zednik, Ricardo
• 金额: $ 1.82万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=669599
• 关键词: Stress; Interface; Engineering; Functional; Materials

Arguably the most important class of functional materials is piezoelectrics. Piezoelectricity, the coupling of mechanical deformation and electrical charge, is the enabling material property for many advanced devices. Current applications, including gyroscopes, accelerometers, and microphones, are essential for the consumer electronics, automotive, and aerospace industries - all important branches of the Canadian economy. In addition, innovative microelectromechanical systems (MEMS), biosensors, and actuators will be needed to develop tomorrow's economy with the "internet of things".***The newest and most innovative devices often require functional materials in highly restricted geometries, such as thin-films and nanofibers. This miniaturization causes materials to behave very differently from the "bulk" materials that have been so well characterized. In addition to interfaces, one of the primary mechanisms by which geometry can affect properties is by locally altering the stress state experienced by the material. This is not only an engineering challenge, but also a design opportunity: how can stress and interface engineering be employed to control the properties of functional materials in these devices?***Efforts to optimize a unique property like piezoelectricity typically involve varying the chemical composition or microstructure. Residual stresses and interfaces are often seen as liabilities rather than powerful tools that can be harnessed to control the underlying physical mechanisms. However, realizing the full potential of functional materials, including piezoelectrics, requires employing all possible methods of manipulation by developing an adequate understanding of governing mechanisms at the restricted geometries applicable to modern devices.***This research program develops a novel method for analyzing these complex stresses and interfaces, and uses it to explore their effect on the fundamental mechanisms in piezoelectric materials. Further, this research program investigates stress and interface engineering as a tool that can go beyond chemical composition and microstructure to realize greatly enhanced material properties that have so far been elusive. In particular, the objectives include enabling high-temperature stable piezoelectric ceramic sensors, as well as powerful piezoelectric polymer nanofibers that can act as flexible biosensors. A thermally stable sensor would be invaluable in the energy and aerospace industries, while a useful piezoelectric polymer would be a boon to the consumer electronics and biomedical fields.**

可以说，最重要的一类功能材料是压电材料。压电是机械变形和电荷的耦合，是许多先进设备的有利材料特性。当前的应用，包括陀螺仪、加速度计和麦克风，对于消费电子、汽车和航空航天工业至关重要，这些都是加拿大经济的重要分支。此外，通过“物联网”发展未来的经济将需要创新的微机电系统 (MEMS)、生物传感器和执行器。***最新和最具创新性的设备通常需要几何形状高度受限的功能材料，例如薄型材料。 -薄膜和纳米纤维。这种小型化导致材料的行为与已被充分表征的“块状”材料非常不同。除了界面之外，几何形状影响性能的主要机制之一是局部改变材料所经历的应力状态。这不仅是一个工程挑战，也是一个设计机会：如何利用应力和界面工程来控制这些设备中功能材料的特性？***优化压电性等独特特性的努力通常涉及改变化学成分或微观结构。残余应力和界面通常被视为负债，而不是可以用来控制底层物理机制的强大工具。然而，要充分发挥包括压电材料在内的功能材料的潜力，需要对适用于现代设备的受限几何形状的控制机制有充分的了解，从而采用所有可能的操纵方法。***该研究项目开发了一种分析这些材料的新方法。复杂的应力和界面，并用它来探索它们对压电材料基本机制的影响。此外，该研究项目还将应力和界面工程作为一种工具进行研究，这种工具可以超越化学成分和微观结构，从而实现迄今为止难以实现的材料性能的大幅增强。具体来说，目标包括实现高温稳定的压电陶瓷传感器，以及可用作柔性生物传感器的强大压电聚合物纳米纤维。热稳定传感器在能源和航空航天工业中将具有无价的价值，而有用的压电聚合物将为消费电子和生物医学领域带来福音。**