Time Dependent Creep Deformation of Non Polar Mixed Conducting Ferroelastic Perovskites

非极性混合导电铁弹性钙钛矿的随时间蠕变变形

• 批准号: 0968911
• 负责人: Nina Orlovskaya
• 金额: $ 26.84万
• 依托单位: The University of Central Florida Board of Trustees
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2014-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0968911&HistoricalAwards=false
• 关键词: Time; Dependent; Creep; Deformation; Non

The proposed research and educational project focuses on time dependent creep deformation of mixed ionic electronic conducting (MIEC) perovskites at room and elevated temperatures. Because a basic understanding of the origin of the time dependent creep is not currently available for lanthanum cobaltites, manganites, chromites, ferrites, and other MIEC conductors, we propose to study creep as a function of external load, loading rate, time, temperature, domain wall mobility, as well as materials composition, crystal structure and grain size. Both experimental and modeling research is proposed to study the mechanisms of time dependent creep deformations, to define driving forces responsible for the phenomena, and to develop new strategies that will allow minimizing the effect of time dependent deformation in MIEC perovskites. A fundamental understanding of time dependent creep in MIEC perovskites is of major importance for further successful development of highly reliable and precise devices such as sensors and actuators, or different electrochemical devices where linear, time independent mechanical output is desirable.The present research program provides an ideal basis for Mechanical and Materials Engineering students to actively participate in project-based learning. Integrated research and educational activities include outreach to a diverse group of high school students and research opportunities for undergraduate students. Graduate students will be involved in research, presentations at technical meetings, and will mentor undergraduate and high school student researchers. Special efforts will be made to attract underrepresented students to pursue their careers in materials science and engineering through high school outreach and undergraduate research.

拟议的研究和教育项目的重点是混合离子电子导电（MIEC）钙钛矿在室温和高温下的时间依赖性蠕变变形。因为一个基本的了解的起源的时间依赖的蠕变是目前没有镧钴酸盐，锰氧化物，铬铁矿，铁氧体，和其他MIEC导体，我们建议研究蠕变作为一个功能的外部负载，加载速率，时间，温度，畴壁迁移率，以及材料的成分，晶体结构和晶粒尺寸。实验和建模研究提出了时间相关的蠕变变形的机制，定义驱动力的现象负责，并制定新的策略，将允许最大限度地减少MIEC钙钛矿的时间相关的变形的影响。对MIEC钙钛矿中随时间变化的蠕变的基本理解对于进一步成功开发高度可靠和精确的设备（如传感器和致动器）或不同的电化学设备（其中需要线性、与时间无关的机械输出）具有重要意义。本研究计划为机械和材料工程专业的学生积极参与基于项目的学习提供了理想的基础。综合研究和教育活动包括推广到不同群体的高中生和研究机会的本科生。研究生将参与研究，在技术会议上演示，并将指导本科生和高中生研究人员。将作出特别努力，以吸引代表性不足的学生追求他们的职业生涯在材料科学和工程通过高中推广和本科研究。