MRI: Acquisition of a Plasma Focused Ion Beam System for Dynamic In-situ Micro-Mechanical Testing Over Cryogenic and Elevated Temperatures

MRI：获取等离子体聚焦离子束系统，用于低温和高温动态原位微机械测试

• 批准号: 2215267
• 负责人: Helen Chan
• 金额: $ 129.83万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2215267&HistoricalAwards=false
• 关键词: MRI; Acquisition; Plasma; Focused; Ion

Direct observation of deformation behavior at the micro/nano scales can lead to significant advances in our understanding of the deformation mechanisms in materials by correlating microstructural changes with load-displacement characteristics. For example, the propagation of a crack-tip that would lead to a catastrophic failure of a component, or deformation/temperature-induced phase transformations and crystallinity changes are important processing phenomena that can lead to failure in materials. The plasma focused ion beam (FIB) in this project allows researchers to efficiently extract samples from specific sites of interest in materials for micromechanical testing, which can be performed using a state-of-the-art micromechanical testing device integrated within the same FIB instrument. It is possible to observe both microstructural and crystallographic changes that occur during deformation using this system, and these changes can be directly correlated with localized stress-strain data. The equipment will benefit a wide variety of funded research activities at Lehigh across sectors of materials science ranging from ceramics, metals/alloys, 3D-printed materials, polymers and biomaterials. In addition, the rapid material removal rate achievable in the plasma FIB accelerates the fabrication of a wide range of nanostructures such as tooling for micro/nano injection molding, as well as enable large-scale internal characterization of various samples including highly sensitive biomaterials and soft polymers at cryogenic temperatures. The instrument also supports research projects from other universities, government labs and industry through liaison programs already established at Lehigh. The techniques and knowledge developed using this system are shared with Lehigh students as well as numerous industry/government attendees of the Lehigh Microscopy Schools. The system as specified consists of (1) a plasma focused ion beam (FIB) instrument, integrated with (2) a state-of-the-art in-situ micromechanical testing device with testing capability over a wide temperature range and (3) a high speed electron backscattered diffraction (EBSD) camera. The system will be able to simultaneously acquire many types of data, including highly sensitive transmission Kikuchi diffraction patterns, during mechanical testing. The rapid milling rate of the Xe-ion based plasma FIB, which is ~10–100 times greater than conventional Ga-ion systems, markedly increases the fabrication throughput of micromechanical test samples, and hence addresses what is currently a severe limitation, namely the ability to test a statistically significant number of samples. In-situ mechanical testing within the FIB at temperatures from minus 130 to 1000 degrees C will enable the correlation of deformation processes (such as slip and microcrack/void nucleation) with microstructural features at the nm scale. Furthermore, the load-displacement signals can be sampled at 1.2 MHz, which is much faster than the typical frame rates encountered in SEM imaging. This information will be complemented by digital image correlation, which will be used to quantify localized deformation. These capabilities are highly advantageous, but what makes the requested instrumentation truly unique is the ability to simultaneously extract real time EBSD data during mechanical testing, which is made possible by a novel test platform geometry. Moreover, the efficiency of serial cross-sectioning for the characterization of multi-component materials, as well as specific features such as interfaces and boundaries in materials and devices, is improved tremendously. The sample sectioning capability at cryogenic temperatures is especially useful for cross-sectional observation of soft materials such as polymers and biological samples, and for thin-specimen preparation to allow more detailed observation in a transmission electron microscope.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

直接观察微/纳米尺度上的变形行为可以通过将微结构变化与负载置换特性相关联，从而导致我们对材料中变形机制的理解的显着进步。例如，裂纹尖端的传播将导致组件的灾难性失败，或变形/温度引起的相变和结晶度变化是重要的处理现象，可能导致材料失败。该项目中的血浆浓缩离子束（FIB）允许研究人员从相同的FIB仪器中集成的最先进的微机械测试装置进行微电测试的材料中有效提取样品。可以观察使用该系统变形过程中发生的微观结构和晶体学变化，并且这些变化可以与局部应力 - 应变数据直接相关。设备将使Lehigh的各种资助研究活动受益于材料科学领域，包括陶瓷，金属/合金，3D打印材料，聚合物和生物材料。此外，在血浆FIB中可实现的快速材料去除率可以加速各种纳米结构的结构，例如用于微/纳米注塑成型的工具，以及在酸sryogenic温度下的各种样品的大规模内部表征，包括高度敏感的生物材料和软聚合物。该工具还通过在Lehigh建立的联络计划来支持其他大学，政府实验室和行业的研究项目。使用该系统开发的技术和知识与Lehigh的学生以及Lehigh显微镜学校的众多行业/政府参与者共享。指定的系统由（1）浓缩的离子束（FIB）仪器组成，该仪器与（2）具有（2）具有测试能力的最先进的现场微机械测试设备在广泛的温度范围内以及（3）高速电子反向散射衍射（EBSD）摄像头。在机械测试期间，该系统将能够轻松地获取许多类型的数据，包括高度敏感的kikuchi衍射模式。基于Xe-Ion的等离子FIB的快速铣削速率比常规GA-ION系统高约10-100倍，显着增加了微机械测试样品的制造吞吐量，因此解决了当前严重限制的问题，即具有统计上大量样品的能力。在从负130至1000度的温度下，FIB内的原位机械测试将使变形过程（例如滑移和微裂纹/无效成核）与NM等级的微结构特征相关。此外，可以在1.2 MHz下采样负载置换信号，该信号比SEM成像中遇到的典型帧速率要快得多。该信息将通过数字图像相关性完成，该相关将用于量化局部变形。这些功能具有很高的优势，但是使请求的仪器真正独特的是能够在机械测试期间简单地提取实时EBSD数据的能力，这是通过新颖的测试平台几何形状实现的。此外，串行横截面对多组分材料表征的表征以及材料和设备中界面和边界等特定特征的效率得到了极大的提高。低温温度下的样品切片能力对于诸如聚合物和生物学样品等柔软材料的横截面观察特别有用，对于薄特性准备，可以在传输电子显微镜中进行更详细的观察。该奖项反映了NSF的法定任务，并通过使用基础的智力效果和广泛的评估来评估，这是NSF的法定任务，并被认为是宝贵的。