Oxide Evolution Dynamics and Stability in Harsh Environments

这笔赠款的研究目的是对单氧化剂和多氧化剂环境中控制早期表面氧化过程的热力学和动力学之间的复杂相互作用有一个详细的基本了解。这项研究将使用先进的高分辨率技术，允许原位询问反应-产物界面，以阐明结构、化学和缺陷的发展。具体地说，将系统地研究在700-1100？C环境中包含O2、H2O、CO2或这些元素的某种组合作为主要氧化剂的镍、镍铬，以及后来的镍铬铝合金。虽然重点是建立以科学为基础的方法来开发和/或改进在实践中发现的许多恶劣环境中使用的先进高温合金和涂层，但所获得的科学理解也将有助于阐明表面反应的集体和耦合行为。如果成功，这种跨学科的合作努力将在重要的气固表面反应领域带来新的范式，如腐蚀、催化、传感器、燃料电池，以及各种电子、磁、医疗和光学设备的合成。这项研究将有助于国家经济竞争力(创造新材料和新技术)，发展有竞争力的STEM劳动力队伍(研究生和博士后培训和指导，跨学科课程)，妇女和代表性不足的少数群体的参与，高中社区外联(宾夕法尼亚州初级科学院)，以及国家安全(可持续能源，能源生产，改进飞机设计)。由于需要向学生介绍以材料为中心的研究和技术的最新发展，各级材料相关课程将在多个部门开发或修改。课程包括气体-金属反应、结晶学、纳米表征、透射电子显微镜和材料科学导论。

The research objective of this grant is to gain a detailed fundamental understanding of the complex interplay between the thermodynamics and kinetics governing early-stage surface-oxidation processes in single- and multi-oxidant environments. The study will use advanced high-resolution techniques to allow in situ interrogation of reaction-product interfaces for elucidating structural, chemical, and defect developments. Specifically, Ni, Ni-Cr, and, later, Ni-Cr-Al alloys in 700-1100¢ªC environments containing O2, H2O, CO2, or some combination of these as primary oxidants will be systematically examined. While the central focus is to establish science-based approaches for developing and/or improving advanced high-temperature alloys and coatings used in the many harsh environments found in practice, the scientific understanding gained will also contribute to elucidating the collective and coupled behaviors of surface reactions in general.If successful, this interdisciplinary collaborative effort will lead to new paradigms in the important field of gas-solid surface reactions, such as corrosion, catalysis, sensors, fuel cells, and synthesis for a variety of electronic, magnetic, medical, and optical devices. The study will contribute to national economic competitiveness (novel materials and technologies created), development of a competitive STEM workforce (training and mentorship of graduate students and post-docs, interdisciplinary courses), the participation of women and underrepresented minorities; high school community outreach (Pennsylvania Junior Academy of Science), and national security (sustainable energy, energy generation, enhanced aircraft design). Materials-related classes at all levels will be developed or modified in multiple departments driven by the need to introduce students to the latest developments in materials-centered research and technology. Examples of classes include Gas-Metal Reactions, Crystallography, Nanocharacterization, Transmission Electron Microscopy, and Introduction to Materials Science.