CAREER: Modeling and Characterization of Microstructure-Induced Toughening in Ceramic Composites with Multiple Micro and Nano Size Scales

9984298这项研究是关于先进陶瓷微观结构增韧效应的计算和实验表征。以具有良好性能的新型TiB_2/Al_2O_3陶瓷复合材料为研究对象，它将(1)提供一种新的细观力学方法用于多种尺度下的显式断裂模拟，(2)表征微观结构形态、相长度尺度、组分性能和界面结合对断裂抗力的影响，(3)阐明多尺度陶瓷复合材料的失效模式和建立失效模型，以及(4)通过微观结构修正确定性能改善的机制。实验将被用来允许外加载荷、时间分辨响应和微观损伤之间的直接关联。该计划的教育部分包括佐治亚理工学院的本科课程开发，向当地高中生和教师宣传招生和工程意识，向少数族裔学生进行招生，以及与当地少数族裔机构进行外联。课程改革认识到了工程力学教育中课堂教学缺乏动手实验的弊端。这一努力的重点是加强佐治亚理工学院的机械工程本科课程，将课堂学习与实验室实验适当地结合起来。这项工作的一个新特点是使用在拟议研究中开发的实验技术，以促进综合工程分析能力的发展。课程创新和推广将使用也用于研究的设施，提供研究生研究、本科生参与、课程开发和推广的自然协同。

9984298This research concerns on the computational and experimental characterization of microstructural toughening effects in advanced ceramics. Focusing on a new TiB2/Al2O3 ceramic composite system with very promising properties, it will (1) yield a novel micromechanical approach for explicit fracture modeling over multiple size scales, (2) characterize the effects of microstructural morphologies, phase length scales, constituent properties, and interphase bonding on fracture resistance, (3) elucidate the failure modes and develop failure models for ceramic composites with microstructures of multiple size scales, and (4) identify mechanisms for property enhancement through microstructural revisions.Combined modeling and experiments will focus on the full, time-dependent process of damage initiation, damage progression and failure using time-resolved diagnostics. Experiments will be used to allow direct correlation of applied loading, time-resolved response, and microscopic damage. The education component of this program consists of undergraduate curriculum development at Georgia Tech, outreach to local high school students and teachers for recruitment and engineering awareness, outreach to minority students for recruitment, and outreach to a local minority institution. The curriculum innovation recognizes the drawback of classroom instruction without hands-on experimentation in engineering mechanics education. This effort focuses on strengthening Georgia Tech's undergraduate curriculum in mechanical engineering through proper integration of classroom learning with laboratory experimentation. A novel feature of this effort is the use of an experimental technique developed in the proposed research to facilitate the development of an aptitude for comprehensive engineering analysis. The curriculum innovation and outreach will use the facilities also used for research, offering a natural synergy of graduate research, undergraduate participation, curriculum development, and outreach.