CAREER: Pressure-Induced Amorphization and Materials Synthesis Under High Pressure Techniques

职业：高压技术下的压力诱导非晶化和材料合成

• 批准号: 9733956
• 负责人: Michael Kruger
• 金额: $ 30万
• 依托单位: University of Missouri-Kansas City
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-15 至 2003-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9733956&HistoricalAwards=false
• 关键词: CAREER; Pressure; Induced; Amorphization; Materials

9733956 Kruger This is a CAREER Award project involving high pressure techniques in two separate areas of research. An objective of the work is to synthesize and study, novel and potentially technologically relevant materials. The research employs pressure-induced amorphization, the pressure-induced destruction of long range crystalline order to produce an amorphous materials. X-ray diffraction study of pressure-amorphized samples will yield the pair correlation function, G(r). The pressure variation of this function will be correlate structures of the pressure-amorphized glasses with the starting crystals, as well as with conventionally synthesized, melt quenched glasses. Raman scattering will be used to study the boson peak of these glasses which will result in a deeper understanding of the glasses as well as the boson peak itself. Numerous theoretical studies have predicted the stability of various phases of carbon nitride, some theoretical studies indicating that certain phases should have bulk moduli rivaling that of diamond. There is significant interest, both theoretical, and practical, in realizing such materials. The PI will apply high pressures and high temperatures to carbon-nitrogen mixtures in order to synthesize some of the theoretically predicted superhard phases of carbon nitride. Study of the equation of state of the materials will help determine which phases are most likely to be superhard, and hence should be made in larger quantities for more detailed study. The education component of this project involves extensive undergraduate research activity, lectures at local high-schools, and mentoring activity associated with the local student Chapter of the American Physical Society. %%% This is a CAREER Award project involves high pressure (up to 100 million atmospheres) techniques to synthesize and study, novel and potentially technologically relevant materials. One relatively recently observed technique employs compression alone to turn a cry stal into a glass. In this way a variety of glasses will be prepared. X-ray and optical scattering techniques will be used to characterize the structural transition from the crystalline to the glassy state. Relationships are sought between the new glasses, the starting crystals, and traditional model glasses. A second project involves the use of high pressures to try to synthesis new, superhard materials. By analogy with the graphite to diamond conversion, high pressures and temperatures will be applied to graphite-nitrogen mixtures in an attempt to synthesize some of the theoretically predicted superhard phases of carbon nitride. The education component of this project involves extensive undergraduate research activity, lectures at local high-schools, and mentoring activity associated with the local student Chapter of the American Physical Society. ***

9733956克鲁格这是一个职业奖项目，涉及两个不同研究领域的高压技术。这项工作的一个目标是合成和研究新颖的、可能与技术相关的材料。本研究采用压力诱导非晶化，在压力诱导下破坏长程晶态有序，产生一种非晶态材料。对加压非晶化样品的X射线衍射研究将得到对关联函数G(R)。这个函数的压力变化将是压力非晶化玻璃的结构与起始晶体以及传统合成的熔融淬火玻璃的相关结构。拉曼散射将被用来研究这些玻璃的玻色子峰，这将导致对玻璃以及玻色子峰本身的更深层次的了解。大量的理论研究预测了氮化碳各相的稳定性，一些理论研究表明，某些相的体积弹性系数应该与金刚石相当。无论是在理论上还是在实践中，实现这种材料都有很大的兴趣。PI将对碳-氮混合物施加高压和高温，以合成一些理论上预测的超硬碳氮化物相。研究材料的状态方程将有助于确定哪些相最有可能是超硬的，因此应该大量生产，以便进行更详细的研究。该项目的教育部分包括广泛的本科生研究活动，在当地高中的讲座，以及与美国物理学会当地学生分会相关的指导活动。%这是一个职业奖项目，涉及高压(高达1亿个大气压)技术，以合成和研究新颖的和潜在的技术相关材料。最近观察到的一种技术是，仅靠压缩就能把哭号变成玻璃杯。通过这种方式，将制备出各种玻璃。X射线和光学散射技术将被用来表征从晶态到玻璃态的结构转变。人们寻求新眼镜、起始水晶和传统模型眼镜之间的联系。第二个项目涉及使用高压来尝试合成新的超硬材料。类似于石墨到金刚石的转化，将在石墨-氮气混合物中施加高压和温度，试图合成一些理论上预测的超硬氮化碳相。该项目的教育部分包括广泛的本科生研究活动，在当地高中的讲座，以及与美国物理学会当地学生分会相关的指导活动。***