Collaborative Research: Ion Irradiation-Induced Nanocrystallization of Metallic Glasses and Its Effects on Their Mechanical Properties

合作研究：离子辐照诱导金属玻璃纳米晶化及其对其机械性能的影响

• 批准号: 1130606
• 负责人: Don Lucca
• 金额: $ 16.02万
• 依托单位: Oklahoma State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2016-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1130606&HistoricalAwards=false
• 关键词: Collaborative; Research; Ion; Irradiation; Induced

The main objectives of this collaborative research project are to develop an understanding of the mechanisms responsible for nanocrystal phase formation when metallic glasses are subjected to ion irradiation, and to quantify the resulting effects on the materials' mechanical behavior. The project will employ monomer-ion irradiation, ion irradiation at elevated temperatures, and cluster ion irradiation to promote direct crystallization of cascade regions so as to achieve tunable crystal densities, sizes and distributions. This portion of the work will contribute to fundamental understanding of radiation responses of metallic glasses including details of ion irradiation induced structural evolution occurring over different time scales involving damage cascade creation, thermal spike formation, and structural relaxation. The project will utilize nanoindentation and micro pillar compression experiments to quantify resulting hardness, elastic modulus and ductility. This portion of work will identify the roles of nanocrystals on the mechanical response of metallic glasses, and contribute to fundamental understanding of shear band nucleation and propagation, and deflection and attenuation by nanocrystals of different mechanical strengths and interaction cross sections.It is expected that this study will contribute to new fundamental understanding of the mechanisms responsible for the creation of nanocrystals in metallic glasses by ion irradiation, and the role of the altered structures in the modification of the materials' mechanical response. Ion irradiation will be used as a method to precisely introduce excessive free volume into a metallic glass, and will therefore provide a means to understand its intrinsic properties, i.e., the role of free volume in determining amorphous-to-crystalline transitions. With nanocrystals embedded in an amorphous matrix acting as stress release centers, the ion beam modified surface is expected to demonstrate enhanced ductility for a wide range of materials applications in harsh environments. The study represents a strong collaboration which reaches across both institutional bounds (university and government laboratories) as well as interdisciplinary bounds (materials science, nuclear engineering, mechanical engineering and applied physics). In addition, the nature of this cross-disciplinary collaboration and the involvement of researchers from several disciplines support the broad dissemination of research results. The proposed effort also includes the integration of our research findings into existing courses at participant universities, and the development of an e-learning module on relevant topics. The project is planned to promote research involvement of underrepresented groups, both as graduate students and undergraduates.

该协作研究项目的主要目标是在金属玻璃受到离子照射时对负责纳米晶相形成的机制的理解，并量化对材料机械行为的影响的影响。该项目将采用单体离子辐照，在升高温度下的离子照射和簇离子辐照以促进级联区域的直接结晶，从而实现可调的晶体密度，尺寸和分布。这部分工作将有助于对金属眼镜的辐射反应的基本理解，包括离子辐射诱导的细节在不同的时间尺度上发生的结构进化，涉及损害级联的创造，热尖峰形成和结构弛豫。该项目将利用纳米凹痕和微柱压缩实验来量化产生的硬度，弹性模量和延展性。这部分工作将确定纳米晶体在金属玻璃的机械响应中的作用，并有助于对剪切条带成核和传播的基本了解，以及纳米晶体的偏转和衰减，从不同的机械强度和相互作用截面的纳米晶体降低和衰减。离子辐照以及改变结构在材料机械响应的修饰中的作用。离子照射将用作准确地将过量的自由体积引入金属玻璃的方法，因此将提供一种理解其内在特性的方法，即自由体积在确定非定形至晶状体过渡中的作用。将纳米晶体嵌入充当应力释放中心的无定形基质中，预计离子束束修饰的表面将证明在恶劣环境中广泛的材料应用中的延展性增强。这项研究代表了一项强大的合作，在机构范围（大学和政府实验室）以及跨学科范围（材料科学，核工程，机械工程和应用物理学）之间达到了良好的合作。此外，这种跨学科合作的性质以及来自多个学科的研究人员的参与支持了研究结果的广泛传播。拟议的努力还包括将我们的研究结果集成到参与者大学的现有课程中，以及开发有关相关主题的电子学习模块。该项目计划促进作为研究生和本科生的代表性不足的群体的研究参与。