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Multiscale Computational and Experimental Analysis of Deformation Mechanisms in Amorphous-Crystalline Metallic Materials with Microstructure Complexity

微结构复杂非晶金属材料变形机制的多尺度计算与实验分析

基本信息

批准号：
1807545
负责人：
Liming Xiong
金额：
$ 46.5万
依托单位：
Iowa State University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-09-01 至 2022-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807545&HistoricalAwards=false
关键词：
Multiscale Computational Experimental Analysis Deformation

项目摘要

NON-TECHNICAL SUMMARYEnhancing the strength of a material is always at the expense of its ability to be purposely deformed or shaped, referred as ductility. Recently, inspired by biological materials, like nacre and dental enamel, a novel metallic composite which combines amorphous alloys (called metallic glass) with crystalline metals, such as copper or aluminum, is shown to have an appreciable strength improvement without sacrificing its ductility. However, up to date, the development of such materials is still at a 'trial and error' stage because: (i) the integration of metallic glass with crystalline metals leads to a complex material microstructure spanning a wide range of length scales from nanometers at the atomic scale to microns; (ii) many existing techniques, which either resolve the material as a collection of atoms or approximate it as a deformable body without considering its internal structure, are incapable to provide a full-scale interpretation on how such material responds to a mechanical forces like tension, compression, or shear. This project supports research addressing these problems through a combined computational and experimental analysis of the deformation in metallic composites over a range of length scales. This research will link the atomistic deformation physics with its overall mechanical performance. Two fundamental questions to be answered are: (a) how does the interface between the amorphous and crystalline phases contribute to their co-deformation? (b) how to architect the metallic composite microstructure such that its failure can be delayed? This research will advance the field by providing researchers with a platform that can be used in a rational design of high-performance materials for a variety of engineering applications such as biomedical implants, aircraft structures, and energy infrastructures. It will expose the next-generation workforce to a broad range of knowledge and skills related to mathematics, physics, mechanics, supercomputing, materials synthesis, processing, and characterization. Moreover, several kits of metallic composites will be developed for illustrating how little changes of the volume amounts of each phase in composites can significantly change its properties. These kits will be presented to science teachers at Gilbert middle and high schools in Iowa for promoting science and engineering to K-12 students.TECHNICAL SUMMARYIn the search of strong and ductile metallic materials, one strategy is introducing interfaces, such as grain boundaries and twin boundaries, to resist dislocation motions. This strategy is usually accompanied by a decrease in ductility although it does lead to an enhancement in strength. By contrast, instead of blocking dislocations, the amorphous-crystalline metallic composites utilize the amorphous phases to absorb dislocations, and may fundamentally change 'the strength-ductility dilemma'. Nevertheless, a methodical engineering approach for developing such composites is not achieved so far due to a knowledge gap in correlating its multi-level microstructure with the overall mechanical performance. This project supports research to fill this gap. The mechanical behavior of amorphous-crystalline metallic composites with microstructure complexities will be analyzed from the atomistic to the microscale. Concurrent atomistic-continuum models that resemble the microstructure of the amorphous-crystalline metallic composite fabricated at the Department of Energy-Ames Laboratory will be developed. Multiscale simulations of plastic flow in such material will be conducted to gain the insight into the interplay between dislocations and shear transformation zones. The intrinsic difference in mechanisms for the deformation in magnetron sputtered orthotropic nano-laminates and ball-milled polycrystalline aggregates will be identified. This research opens up the possibility of architecting the metallic composites microstructure for a desired property. Many aspects of this research will not be limited to metals but are readily extendable to other classes of materials, such as biomimetic ceramics, metallic glass-based composites for electromechanical devices, corrosion-, and radiation-resistant materials for nuclear power plants.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.

非技术概述增强材料的强度总是以牺牲其有目的地变形或成形的能力为代价，称为延展性。最近，受珍珠层和牙釉质等生物材料的启发，将非晶合金（称为金属玻璃）与结晶金属（例如铜或铝）结合的新型金属复合材料显示出具有明显的强度改善而不牺牲其延展性。然而，到目前为止，这种材料的开发仍然处于“试错”阶段，因为：（i）金属玻璃与晶体金属的集成导致复杂的材料微观结构，其跨越从原子尺度的纳米到微米的宽范围的长度尺度;（ii）许多现有技术，其将材料分解为原子的集合或将其近似为可变形体而不考虑其内部结构，不能提供关于这种材料如何响应于机械力（如拉伸、压缩或剪切）的全面解释。该项目通过对金属复合材料在一系列长度尺度上的变形进行计算和实验分析，支持解决这些问题的研究。这项研究将把原子变形物理与其整体力学性能联系起来。要回答的两个基本问题是：（a）非晶相和晶相之间的界面如何有助于它们的共同变形？(b)如何设计金属复合材料的微观结构，使其失效可以延迟？这项研究将通过为研究人员提供一个平台来推动该领域的发展，该平台可用于各种工程应用的高性能材料的合理设计，如生物医学植入物，飞机结构和能源基础设施。它将使下一代劳动力接触到与数学，物理，力学，超级计算，材料合成，加工和表征相关的广泛知识和技能。此外，将开发几套金属复合材料，以说明复合材料中每相体积量的微小变化如何显著改变其性能。这些工具包将提交给爱荷华州的吉尔伯特初中和高中的科学教师，用于向K-12学生推广科学和工程学。技术概述在寻找强韧性金属材料时，一种策略是引入界面，如晶界和孪晶界，以抵抗位错运动。这种策略通常伴随着延展性的降低，尽管它确实导致强度的增强。相比之下，非晶-晶态金属复合材料利用非晶相吸收位错，而不是阻挡位错，并可能从根本上改变“强度-塑性困境”。然而，一个有条不紊的工程方法来开发这样的复合材料是没有实现到目前为止，由于知识差距，在关联其多层次的微观结构与整体的机械性能。该项目支持填补这一空白的研究。将从原子尺度到微观尺度分析具有复杂微观结构的非晶-结晶金属复合材料的力学行为。并行原子连续模型，类似于在能源部埃姆斯实验室制造的非晶-结晶金属复合材料的微观结构将被开发。在这种材料的塑性流动的多尺度模拟将进行深入了解位错和剪切转变区之间的相互作用。磁控溅射正交各向异性纳米层压板和球磨多晶聚集体的变形机制的内在差异将被确定。这项研究开辟了为所需性能构建金属复合材料微观结构的可能性。这项研究的许多方面将不仅限于金属，而且可以很容易地扩展到其他类别的材料，如仿生陶瓷，机电设备的金属玻璃基复合材料，核电站的耐腐蚀和辐射材料。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。