Acquisition of an Automated Digital Transmission Electron Microscope

9626279史密斯，即透射式电子显微镜，四十年来一直是材料研究的中流砥柱，至今仍是世界上最重要的科学仪器之一。在过去的20年里，利哈伊一直在分析性的瞬变电磁研究和对瞬变电磁用户的教育方面保持领先地位。该合同提供了部分资金，用于购买用于材料化学和结构成像的自动数字透射式电子显微镜(ADTEM)，重点是现场研究。ADTEM将结合更好的0.23 nm分辨率和30%的倾斜度，可在各种侧入样品支架上使用。该显微镜将配备一个电子能量过滤器，可以产生高清晰度的能量过滤图像和衍射图案。其中包括加强和升级标本制备设备和图像分析设施的支持。数字采集的图像将可以从校园内外的任何联网终端访问。收购拟议中的ADTEM将在四个主要领域影响这些正在进行或计划中的研究计划：1)薄膜，2)非晶态和纳米结构，3)陶瓷和陶瓷复合材料，以及4)环境敏感断裂。20多名教职员工的研究计划将受到拟议的ADTEM的影响。薄膜领域的研究项目包括用于磁信息存储的CoPT的研究以及Nb/Al、Ni/Al和Ti/Al多层膜反应中晶界扩散和晶界结构的作用。在非晶态和纳米尺度结构的推动下，无机和有机材料的各种研究正在进行中：非晶态硅的晶化，具有优化的颗粒结构的铜互连的发展，EXELFS测定无机玻璃中轻原子周围的结构，用于增韧工程塑料的核/壳颗粒的新设计概念，以及束敏感催化材料的能量过滤衍射。在陶瓷和陶瓷复合材料的推力领域，正在研究开发超蠕变氧化物的晶界化学，纳米复合材料的加工和性能，以及为获得最佳力学性能的功能梯度氧化铝/铝复合材料的反应形成。环境敏感断裂的最后一个推力领域的研究计划涉及高温合金蠕变裂纹扩展的环境和随机方面以及铝合金的腐蚀和疲劳。ADTEM的教育作用将是在各种本科生和研究生课程的实验室部分演示高分辨率结构成像、高级衍射和能量过滤显微镜。来自这台显微镜的数字图像将由学生在我们现有的IBM RS6000集群和拟议的Macintosh 8100集群中离线分析。***

9626279 Smith The transmission electron microscope (TEM) has been a mainstay of materials research for about forty years and remains one of the world's most important scientific instruments. Over the last 20 years Lehigh has maintained a leadership position in analytical TEM research and in the education of TEM users. This award provides funds in partial support of the purchase of an automated digital transmission electron microscope (ADTEM) for chemical and structural imaging of materials with an emphasis on in-situ studies. The ADTEM will combine better than 0.23 nm resolution with 30 of tilt in a variety of side entry specimen holders. The microscope will feature an electron energy filter which can produce high clarity energy-filtered images and diffraction patterns. Included is support for enhancing and up-grading the specimen preparation equipment and image analysis facilities. The digitally acquired images will be accessible from any networked terminal on or off campus. %%% The acquisition of the proposed ADTEM will impact these ongoing or planned research programs in the four thrust areas of: 1) thin films, 2) amorphous and nanoscale structures, 3) ceramics and ceramic composites, and 4) environment-sensitive fracture. The research programs of more than 20 faculty will be impacted by the proposed ADTEM. The research programs in the area of thin films include a study of CoPt for magnetic information storage and the role of grain structure and grain boundary diffusion in the reaction of Nb/Al, Ni/Al and Ti/Al multilayers. Under the thrust area of amorphous and nanoscale structures a variety of studies in inorganic and organic materials are being pursed: crystallization of amorphous silicon, development of copper interconnects with optimized grain structures, determination of structure around light atoms in inorganic glasses by EXELFS, novel design concepts in core/shell particles for toughening engineering plastics, and energy filtered diffracti on of beam sensitive catalyst materials. In the thrust area of ceramics and ceramic composites, tailoring of grain boundary chemistry for the development of super creep-resistant oxides, processing and properties of nanocomposites, and reaction forming of functionally gradient aluminum oxide/aluminum composites for optimal mechanical properties are under investigation. The research programs in the last thrust area of environment- sensitive fracture address environmental and stochastic aspects of creep crack growth in super-alloys and corrosion and fatigue of aluminum alloys. The educational role of the ADTEM will be to demonstrate high resolution structure imaging, advanced diffraction, and energy filtered microscopy in the laboratory section of a variety of undergraduate and graduate courses. Digital images from this microscope will be analyzed by students off-line in our existing cluster of IBM RS6000s and proposed cluster of Macintosh 8100s. ***