Collaborative Research: Mechanisms of hierarchical microstructure formation under rapid solidification of functional Heusler alloys

合作研究：功能霍斯勒合金快速凝固下分级显微结构形成机制

• 批准号: 1808145
• 负责人: Carolin Fink
• 金额: $ 21.54万
• 依托单位: Ohio 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: 2018-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1808145&HistoricalAwards=false
• 关键词: Collaborative; Research; Mechanisms; hierarchical; microstructure

Non-Technical Description: Functional magnetic materials can have outstanding properties. Magnetic shape memory alloys change from one shape to another with the application of a magnetic field, and can potentially replace mechanical actuators that currently need several moving parts that are difficult to assemble and might break easily. Magnetocaloric materials have a characteristic that allows them to cool or heat when exposed to a magnetic field, and might be used as cooling devices without the need of liquids and compressors currently required in refrigerators. Presently, it is difficult to fabricate complex parts of functional magnetic materials. Advanced, laser or electron beam manufacturing techniques offer the ability to print very complex shapes, but create challenging microstructures that result in non-functional parts. This award supports research that will establish a fundamental understanding between advanced manufacturing parameters, composition, microstructure and properties, and enable advanced manufacturing of magnetic materials with a targeted set of functions, or behaviors. The approach employs an innovative combination of rapid cooling and solidification processing and small-scale experiments, with extensive computational modeling, and validation experiments and characterization. The gained knowledge is expected to reduce barriers for further adoption of functional magnetic materials beyond prototypes in a large variety of fields and currently out-of-reach applications, e.g. printable actuators, pumps and solid cooling devices. The combination of functional materials, computer modelling, and advanced manufacturing will be used to create experience-based STEM outreach activities for K-12 students, their teachers and parents. These demonstrations and hands-on experiments will take place at local schools, summer schools and outreach events which serve especially economically challenged and underrepresented students populations. The training of undergraduate and graduate students in this multidisciplinary research environment will enhance the students' preparedness for fast-changing, multifaceted and collaborative work place. The results of this research will be presented in research journals and conferences, but also through blog-posts, social media and openly accessible videos.Technical Description:Functional Heusler alloys such as magnetic shape-memory alloys or magnetocaloric materials induce up to 10% strain under an applied magnetic field and actuate nearly as fast as piezoceramics, or enable solid-state cooling with up to 30% better efficiency than traditional technologies. Presently, the fabrication of complex shaped parts with good functional properties is very limited, compromising a broad application of these materials. Advanced, laser and electron beam manufacturing techniques enable complex build design, but create challenging microstructures due to rapid heating, melting and solidification, and result in non-functional or low functionality parts. This award supports an integrated experimental and computational research that aims to improve our fundamental understanding between composition, microstructure and functional properties in Ni-Mn-Ga based Heusler alloys subjected to rapid solidification and cyclic heating in layer-based advanced manufacturing and post-processing. Research efforts pursue the following goals: (A) Identify fundamental relations between alloy composition, microstructure and properties under far-from-equilibrium rapid solidification and cyclic heating conditions, (B) develop CALPHAD-based predictive models for nonequilibrium phase formations, micro-segregation behavior and magnetic properties, and (C) establish composition and grain size control in layered deposits of functional Heusler alloys through targeted rapid solidification processing and post-heat treatment. The outcome of this research will enable laser-based deposition of Heusler alloys and permit functional, complex shaped, self-limiting actuator components (magnetic shape-memory alloys) and highly efficient solid-state cooling devices (magnetocaloric materials).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.

非技术说明：功能磁性材料可以具有出色的性能。磁性形状记忆合金通过施加磁场从一种形状转变为另一种形状，并且有可能取代目前需要多个难以组装且可能容易损坏的移动部件的机械致动器。磁热材料具有一种特性，可以在暴露于磁场时冷却或加热，并且可以用作冷却装置，而不需要冰箱目前所需的液体和压缩机。目前，功能磁性材料的复杂零件的制造比较困难。先进的激光或电子束制造技术能够打印非常复杂的形状，但会产生具有挑战性的微观结构，从而导致无法正常工作的部件。 该奖项支持的研究将在先进制造参数、成分、微观结构和性能之间建立基本了解，并实现具有一组目标功能或行为的磁性材料的先进制造。该方法采用快速冷却和凝固处理与小规模实验的创新组合，以及广泛的计算建模、验证实验和表征。所获得的知识预计将减少在各种领域和目前遥不可及的应用中进一步采用功能性磁性材料（超越原型）的障碍。可打印的执行器、泵和固体冷却装置。功能材料、计算机建模和先进制造的结合将用于为 K-12 学生、教师和家长打造基于体验的 STEM 外展活动。这些演示和实践实验将在当地学校、暑期学校和外展活动中进行，这些活动专门为经济困难和代表性不足的学生群体提供服务。在这个多学科研究环境中对本科生和研究生的培训将增强学生对快速变化、多方面和协作工作场所的准备。这项研究的结果将在研究期刊和会议上公布，同时也会通过博客文章、社交媒体和公开视频的形式公布。技术描述：功能性霍斯勒合金（例如磁性形状记忆合金或磁热材料）在外加磁场下可产生高达 10% 的应变，并且驱动速度几乎与压电陶瓷一样快，或实现固态冷却，效率比传统技术高出 30%。目前，具有良好功能特性的复杂形状零件的制造非常有限，影响了这些材料的广泛应用。先进的激光和电子束制造技术可实现复杂的构建设计，但由于快速加热、熔化和凝固而产生具有挑战性的微观结构，并导致无功能或低功能部件。该奖项支持综合实验和计算研究，旨在提高我们对 Ni-Mn-Ga 基 Heusler 合金成分、微观结构和功能特性的基本了解，这些合金在层状先进制造和后处理中经受快速凝固和循环加热。研究工作追求以下目标：（A）确定远非平衡快速凝固和循环加热条件下合金成分、微观结构和性能之间的基本关系，（B）开发基于 CALPHAD 的非平衡相形成、微观偏析行为和磁性的预测模型，以及（C）通过有针对性的快速凝固处理和 后热处理。这项研究的成果将实现赫斯勒合金的激光沉积，并允许功能性、复杂形状、自限性执行器组件（磁性形状记忆合金）和高效固态冷却装置（磁热材料）。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。

项目成果

Effect of rapid solidification and post-processing on microstructure, magnetic and structural transition temperatures and magnetic properties in Ni50Mn29Ga21 magnetic shape-memory alloy

快速凝固和后处理对Ni50Mn29Ga21磁性形状记忆合金显微组织、磁性和结构转变温度以及磁性能的影响

• DOI: 10.1016/j.actamat.2023.119325
• 发表时间: 2023
• 期刊: Acta Materialia
• 影响因子: 9.4
• 作者: Flitcraft, Emily;De Vecchis, Pierangeli Rodriguez;Kuprienko, Alexey;Chmielus, Markus;Fink, Carolin
• 通讯作者: Fink, Carolin