DMREF-A Combined Experiment and Simulation Approach to the Design of New Bulk Metallic Glasses

* 技术摘要 * 该项目支持开发一种新的、迭代的大块金属玻璃（BMG）合金设计方法，以推进材料基因组计划（MGI）的目标。这种发展需要一个全面的方法，处理动态的液体，这是必不可少的玻璃化转变，和结晶，必须避免形成玻璃，在平等的基础上，连接的液体和玻璃的结构。实现这一目标需要将实验和模拟与紧密的反馈相结合。这些实验包括新型的高热速率，高通量的闪光DSC来测量整个时间-温度-转变曲线和液体脆性，以及波动电子显微镜（FEM）来测量新的，否则无法获得的有关纳米级结构顺序的信息。模拟包括加速分子动力学，以连接结构到液体动力学和结晶沿着的开发和发布的一个新的反向结构测定软件工具，结合有限元数据和从头算哈密顿使用遗传优化和贝叶斯统计。新的方法将应用于开发新的，笨重的铝基金属玻璃，从铝钐和铝镧系统，稳定的微量合金化。一个更大的目标是揭示组成，结构，原子动力学和结晶之间的基本新联系;这些将用于创建通用，直观的簇设计规则，以开发新的BMG。非技术摘要 * 块体金属玻璃（BMG）是可以从液体冷却而不结晶的合金，从而产生玻璃状的非晶固体。如果温度保持在过冷液体区域中，则足够稳定的BMG可以像塑料一样加工，从而通过吹塑成型和通过硬掩模压印在大面积上快速制造纳米结构来实现复杂形状的净形状、无缝成形。新的应用包括包装，动脉支架，水净化，微型齿轮和弹簧。该项目将开发一种新的方法来发现新的BMG合金，使用最先进的实验和计算工具的迭代策略，推进材料基因组计划（MGI）的目标。该方法需要将实验和模拟与四名研究人员之间的紧密反馈相结合，并提供新的科学见解。新的综合计算和实验的方法，结合结构到纳米尺度和动力学的玻璃形成和结晶，可能是革命性的产生一个独特的组合的工具和方法，可能会导致一个通用的方法来设计新的BMG合金的各种应用。该项目支持学生和博士后在合作环境中进行实验和计算材料研究的教育，以及为年轻学生和公众开发推广材料和演示。该奖项由材料研究部（DMR）和数学科学部（DMS）资助。

****Technical Abstract****This project supports development of a new, iterative alloy design methodology for bulk metallic glass (BMG) alloys that advances the objectives of the Materials Genome Initiative (MGI). This development requires a comprehensive approach, treating dynamics in the liquid, which are essential to the glass transition, and crystallization, which must be avoided to form a glass, on an equal footing, connected by the structure of the liquid and the glass. Achieving this goal requires the integration of experiments and simulations with tight feedback. The experiments include novel high-thermal-rate, high-throughput flash DSC to measure entire time-temperature-transformation curves and liquid fragility, and fluctuation electron microscopy (FEM) to measure new, otherwise inaccessible information about nanoscale structural order. Simulations include accelerated molecular dynamics to connect structure to liquid dynamics and crystallization along with the development and release of a new reverse structure determination software tool incorporating FEM data and ab initio Hamiltonians using genetic optimization and Bayesian statistics. The new methodology will be applied to develop new, bulkier Al-based metallic glasses, starting from the Al-Sm and Al-La systems, stabilized by minor alloying. A larger goal is to uncover fundamental new connections between composition, structure, atom dynamics, and crystallization; these will be used to create general, intuitive, cluster design rules to develop new BMGs.****Non-Technical Abstract****Bulk metallic glasses (BMGs) are alloys that can be cooled from the liquid without crystallization, resulting in a glassy, amorphous solid. Sufficiently stable BMGs can be processed like plastics if the temperature is held in the supercooled liquid region, resulting in net-shape, seamless forming of complicated shapes by blow molding and rapid fabrication of nanostructures across large areas by hard-mask imprinting. New applications include packaging, arterial stents, water purification, and miniature gears and springs. This project will develop a new methodology for discovering new BMG alloys using an iterative strategy of state-of-the-art experimental and computational tools that advances the objectives of the Materials Genome Initiative (MGI). The method requires the integration of experiments and simulations with tight feedback between the four investigators with complimentary expertise to provide new scientific insights. The novel integrated computational and experimental approach, combining structure up to the nanometer scale and the kinetics of both glass formation and crystallization, may be transformative in yielding a unique combination of tools and approaches that may lead to a general method to design new BMGs alloys for a variety of applications. This project supports the education of students and post-docs in combined experimental and computational materials research in a collaborative environment, and development of outreach materials and demonstrations for younger students and the general public.This award is funded by the Division of Materials Research (DMR) and the Division of Mathematical Sciences (DMS).