Mechanical Behavior of Novel Metal-Oxide Composites with Hierachical Microstructures: Effect of Scale and Interfacial Structure

具有分级微观结构的新型金属氧化物复合材料的力学行为：尺度和界面结构的影响

• 批准号: 1507955
• 负责人: Helen Chan
• 金额: $ 46.06万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1507955&HistoricalAwards=false
• 关键词: Mechanical; Behavior; Novel; Metal; Oxide

NON-TECHNICAL DESCRIPTION: Often, a material with nanometer-sized internal features has remarkable properties such as high strength (when compared to the same material with larger features). However, it can be difficult to create such materials with these nanometer-scale features at an affordable cost and in large quantities. This research project is focused on a new route for creating materials with nanometer-scale layers of ceramics and metals that have the potential to possess unusual and advantageous mechanical properties and to be processed at a reasonable cost. Electron microscopy techniques and specialized small-scale mechanical tests are revealing the role of the ceramics-metal interfaces, the orientation of the individual phases, and the size of the phases on mechanical properties. The results are providing a fundamental scientific understanding of these phenomena that can be applied to fields such as joining of ceramics and metals, creation of strong materials for load-bearing applications, and prevention of failure in microelectronic devices. In addition, the broad scientific concepts developed during this work are being incorporated into outreach activities that target K-12 children, thereby encouraging their participation in science and engineering fields.TECHNICAL DETAILS: This research project is focused on understanding the microstructure development and mechanical behavior of ceramic-metal composites derived from the partial reduction of mixed oxide ceramics that have a delafossite starting structure. Reducing this class of materials to partially remove oxygen yields a hierarchical structure with unique ceramic-metal composite morphologies that hitherto have not been studied and that promise to exhibit attractive mechanical properties. The microstructural scale of the ceramic/metal features range from tens of nanometers to tens of microns, and both layered and globular morphologies can be achieved. The discovery of a unique microstructure that can be created by reducing delafossite materials, combined with the relatively recent advent of aberration-corrected scanning transmission electron microscopes and in situ micro-mechanical testing instruments, make it possible for the first time to reveal the effects of ceramic-metal nanocomposite microstructure scale and lamellar orientation on stiffness, hardness, and toughness. The findings of the study are relevant to technological processes such as joining, and to understanding scaling effects in ceramic-metal systems. Additionally, university-level students are developing expertise in the emerging areas of aberration-corrected scanning transmission electron microscopy and in situ micro-mechanical testing.

非技术描述：通常，具有纳米级内部特征的材料具有显著的特性，例如高强度（与具有更大特征的相同材料相比）。然而，以可承受的成本和大量生产具有这些纳米级特征的材料是很困难的。该研究项目的重点是创造纳米级陶瓷和金属层材料的新途径，这些材料具有不寻常和有利的机械性能，并且可以以合理的成本进行加工。电子显微镜技术和专门的小规模力学测试揭示了陶瓷-金属界面的作用，单个相的取向，以及相的尺寸对力学性能的影响。这些结果为这些现象提供了基本的科学理解，可以应用于陶瓷和金属的连接，为承载应用创造坚固材料，以及防止微电子设备故障等领域。此外，在这项工作中形成的广泛的科学概念正在纳入以K-12儿童为对象的外联活动，从而鼓励他们参与科学和工程领域。技术细节：本研究项目的重点是了解陶瓷-金属复合材料的微观结构发展和力学行为，这些复合材料是由具有延迟岩起始结构的混合氧化物陶瓷部分还原而来的。减少这类材料以部分去除氧会产生具有独特陶瓷-金属复合形态的分层结构，这种结构迄今尚未被研究过，并且有望表现出吸引人的机械性能。陶瓷/金属特征的微观结构尺度从几十纳米到几十微米不等，可以实现层状和球状形态。通过减少delafosite材料而产生的独特微观结构的发现，结合相对较新出现的像差校正扫描透射电子显微镜和原位微机械测试仪器，使得首次揭示陶瓷-金属纳米复合材料微观结构的规模和片层取向对刚度、硬度和韧性的影响成为可能。该研究结果与连接等工艺过程有关，并有助于理解陶瓷-金属体系中的结垢效应。此外，大学水平的学生正在发展像差校正扫描透射电子显微镜和原位微机械测试等新兴领域的专业知识。

项目成果

A novel ceramic derived processing route for Multi-Principal Element Alloys

• DOI: 10.1016/j.msea.2020.139892
• 发表时间: 2020-07
• 期刊: Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
• 影响因子: 6.4
• 作者: M. Gianelle;A. Kundu;K. P. Anderson;A. Roy;G. Balasubramanian;H. M. Chan