EAGER: IMPRESS-U: Gradient surface nanostructuring with short laser pulses

EAGER：IMPRESS-U：使用短激光脉冲进行梯度表面纳米结构

• 批准号: 2406599
• 负责人: Leonid Zhigilei
• 金额: $ 29.79万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-03-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2406599&HistoricalAwards=false
• 关键词: EAGER; IMPRESS; Gradient; surface; nanostructuring

The rapidly growing industrial demand for high-performance materials exhibiting a combination of high strength and hardness, substantial ductility, and fatigue resistance has been driving the development of so called “nanostructured materials,” where a high density of crystal defects (grain boundaries, twins, stacking faults and dislocations) can lead to a striking enhancement of the mechanical properties. The utilization of nanostructured materials, however, is limited by their poor thermal stability against grain coarsening and defect annihilation, as well as difficulties of the scale-up of existing synthesis techniques and their integration into modern manufacturing processes. This EArly-concept Grant for Exploratory Research (EAGER) International Multilateral Partnerships for Resilient Education and Science System in Ukraine (IMPRESS-U) award supports the exploration of a novel non-contact approach to surface nanostructuring based on a simultaneous generation of a high density of crystal defects by short pulse laser processing and stabilization of these defects through the laser-assisted nanoalloying. The goal of this project is to provide a proof of concept for the feasibility of a nimble laser-assisted defect engineering and stabilization, pushing forward the frontiers of the laser processing technologies. The project benefits from the complementary expertise and existing research links between the members of the international research team from the United States, Lithuania, and Ukraine. One of the major goals of the project is to establish a long-term sustainable collaboration fully integrating Ukrainian researchers into the global research community. Mutual visits, exchange of research expertise, and educational activities create a fertile ground for the emergence of a new area of research strength at the Lviv Polytechnic National University. In particular, the best practices of a well-established Center of Laser Technologies in Vilnius, Lithuania are adopted by the research center emerging at Lviv Polytechnic. Leveraging computational expertise at the University of Virginia grounds investigations at the Ukrainian research center on solid fundamental understanding of processes underlying material modifications from short pulse laser processing.The challenge of revealing and untangling the intertwined processes responsible for the generation of various crystal defects in laser nanostructuring is addressed in this project by combining large-scale atomistic modeling of laser-induced structural and phase transformations, advanced large-area non-ablative laser processing using a novel setup for nanoalloying, and nanoscale characterization of the laser-modified surfaces. The stabilization of laser-generated highly nonequilibrium defect structures through nanoalloying is achieved by adding alloying elements that preferentially segregate to grain boundaries and other defects, thus reducing the free energy of nanocrystalline structures and acting as obstacles for defect migration. The fundamental mechanisms responsible for the generation of crystal defects at a rapidly advancing crystallization front and their stabilization through nanoalloying is systematically investigated in atomistic simulations. The conditions of the simulations are mapped to those realized in laser processing, and the computational predictions are verified in a detailed experimental characterization of surface regions modified by short pulse laser irradiation. The direct mapping of the computational predictions to the results of nanoscale characterization of laser modified surfaces guides the exploration of the multidimensional space of laser processing parameters and enables the verification and refinement of the model assumptions. Several strategies for expanding the range of irradiation conditions leading to nanocrystallization are explored, including suppression of subsurface cavitation and spallation by performing laser processing in a liquid environment and under confinement by a transparent solid overlayer. The effect of alloying/compositional gradients on the solidification kinetics and final nanostructure are systematically investigated for different target configurations in simulations and experiments.This EAGER: IMPRESS-U project is jointly funded by NSF, Research Council of Lithuania, US National Academies of Sciences, and Office of Naval Research Global (DoD). US portion of this collaborative partnership project is supported by NSF Office of International Science and Engineering (Office of the Director), CMMI’s Advanced Manufacturing Program (Engineering Directorate), and DMR’s Metals and Metallic Nanostructures Program (Directorate for Mathematical and Physical Sciences).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.

对高性能材料的迅速增长的工业需求，进行了高强度和硬度，实质性延展性和抗疲劳性的结合一直在推动所谓的“纳米结构材料”的发展，其中高密度的晶体缺陷（晶粒边界，双胞胎，双胞胎，堆叠缺陷和错位）可能会导致该机能的增强物质。然而，纳米结构材料的利用受到其对谷物粗糙和缺陷灭绝的较差的热稳定性的限制，以及现有合成技术扩大规模的难度以及它们整合到现代制造过程中。这项早期概念概念授予探索性研究（急切）国际国际多边伙伴关系在乌克兰的弹性教育和科学系统（Impress-U）奖（Impress-U）奖支持探索一种新型的非接触纳米结构方法，这些方法是基于短脉冲激光器加工和稳定效果的高密度晶体缺陷的简单产生的，这些方法是通过这些稳定的稳定来探索。该项目的目的是为敏捷的激光辅助缺陷工程和稳定提供可行性提供概念证明，从而推动了激光处理技术的前沿。该项目受益于美国，立陶宛和乌克兰国际研究团队成员之间的完整专业知识和现有研究联系。该项目的主要目标之一是建立长期可持续合作，将乌克兰研究人员完全融合到全球研究界。相互访问，研究专业知识的交流和教育活动为在LVIV理工国立大学出现新的研究实力领域创造了肥沃的基础。特别是，LITHUANIA维尔纽斯的激光技术中心的最佳实践被LVIV理工学院的研究中心采用。弗吉尼亚大学理由的计算专业知识在乌克兰研究中心研究中心对简短脉冲激光器处理的材料修改的稳定基本了解的研究中心进行调查。通过结合激光诱导的结构和相变的大规模原子建模，使用新型的nanoeralyaloying和nanoscearization surfization nanoscearization，揭示和解开揭示和解开负责在激光纳米结构中产生各种晶体缺陷的过程的挑战，可以解决激光诱导的结构和相变的大规模原子建模。通过添加优先脱离晶粒边界和其他缺陷的合金元素来实现激光生成的高度非平衡缺陷结构的稳定，从而降低了纳米晶结构的自由能，从而降低了缺陷迁移的障碍。在原子模拟中系统地研究了导致快速前进的结晶前晶体缺陷及其通过纳米合金稳定的基本机制。模拟的条件映射到激光处理中实现的条件，并在通过短脉冲激光辐照修饰的表面区域的详细实验表征中验证了计算预测。将计算预测直接映射到激光修饰表面的纳米级表征结果的指导指导激光处理参数的多维空间的探索，并启用模型假设的验证和完善。探讨了扩大导致纳米结晶的辐射条件范围的几种策略，包括通过在液体环境中进行激光加工并被透明的固体覆盖剂限制，抑制地下气蚀和散布。合金/组成梯度对固化动力学和最终纳米结构的影响是在模拟和实验中的不同目标配置的系统研究。这急切：Impress-U项目由NSF共同资助，由立陶宛研究委员会联合资助，美国国家研究委员会，美国国家科学研究院和Naval Research Global（DOD）。 US portion of this collaborative partnership project is supported by NSF Office of International Science and Engineering (Of​​fice of the Director), CMMI’s Advanced Manufacturing Program (Engineering Directorate), and DMR’s Metals and Metallic Nanostructures Program (Directorate for Mathematical and Physical Sciences).This award reflects NSF's statutory mission and has been deemed precious of support through evaluation using the Foundation's intellectual merit and broader impacts review 标准。