Collaborative Research: Elucidating High Temperature Deformation Mechanisms in Refractory Multi-Principal-Element Alloys

合作研究：阐明难熔多主元合金的高温变形机制

• 批准号: 2313861
• 负责人: Irene Beyerlein
• 金额: $ 48.2万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2313861&HistoricalAwards=false
• 关键词: Collaborative; Research; Elucidating; Temperature; Deformation

NON-TECHNICAL SUMARYModern transportation, power generation, space access, and national security all rely on the availability of materials that can maintain their shape and strength at elevated temperatures. The development of nickel-based superalloys, which often contain ten or more elements, are used in jet engines, can withstand temperatures of over 1,000oC, and allow for gas temperatures in excess of 1,400oC. The development of multiple generations of these superalloys occurred over many decades but is reaching its limit. Further temperature advancements would result in better fuel efficiencies, greater thrust, and optimal performance, but novel approaches to alloy development are required. The use of refractory elements that have higher melting temperatures and the creation of equiatomic alloys represent two promising paths forward, but current understanding of how these new alloys deform at extreme temperatures is currently lacking. This study combines advanced computational modeling with novel ultrahigh temperature experiments and detailed electron microscopy to identify the deformation mechanisms that govern the high temperature strength of this new class of refractory multi-principal-element alloys. The proposed collaboration is both rapidly accelerating the rate of alloy discovery while providing meaningful educational and career advancement opportunities, thus expanding and enlarging the workforce in automotive, aerospace, and national defense sectors.TECHNICAL SUMMARYRefractory-multi-principal-element alloys (RMPEAs) hold tremendous potential for use as structural materials that can operate at ultrahigh temperatures (UHT) and in the extreme environments required for energy efficient power generation, hypersonic flight, and space access. Targeted use temperatures cannot be met with conventional superalloys, and current understanding of the UHT mechanical behavior of RMPEAs is still in its infancy and represents a critical impediment to the realization of this new class of alloys. The scientific merit of the proposed research is predicated on the overwhelming need to predict, characterize, and understand the deformation mechanisms that govern the mechanical response of RMPEAs at temperatures approaching 1500oC. The integration of advanced mesoscale modeling of dislocation dynamics, novel sub-scale mechanical testing, and detailed microstructural characterization are being used to gather much needed UHT tensile and creep data to develop a fundamental scientific description of the ultrahigh temperature deformation of nearly equiatomic, compositionally complex, multicomponent alloys. Participation in established programs at Johns Hopkins University and the University of California, Santa Barbara are providing research experiences for under-represented high school and undergraduate students, and the proposed undergraduate student exchanges hold real potential for expanding the pipeline of STEM graduate students, and in time, STEM leaders and role models.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.

非技术性总结现代交通、发电、太空访问和国家安全都依赖于能够在高温下保持其形状和强度的材料的可用性。 镍基高温合金的开发通常含有十种或更多元素，用于喷气发动机，可以承受超过 1,000oC 的温度，并允许气体温度超过 1,400oC。 这些高温合金的多代开发经历了数十年，但已达到极限。 温度的进一步进步将带来更好的燃油效率、更大的推力和最佳的性能，但需要新的合金开发方法。 使用具有更高熔化温度的难熔元素和创建等原子合金代表了两条有希望的前进道路，但目前缺乏对这些新合金在极端温度下如何变形的了解。 这项研究将先进的计算模型与新颖的超高温实验和详细的电子显微镜相结合，以确定控制此类新型难熔多主元素合金的高温强度的变形机制。拟议的合作既可以迅速加快合金发现的速度，同时提供有意义的教育和职业发展机会，从而扩大和扩大汽车、航空航天和国防领域的劳动力。 技术摘要难熔多主元素合金 (RMPEA)作为可在超高温 (UHT) 和节能发电、高超音速飞行和太空访问所需的极端环境下运行的结构材料，具有巨大的潜力。传统高温合金无法满足目标使用温度，目前对 RMPEA 的 UHT 机械行为的理解仍处于起步阶段，是实现此类新型合金的关键障碍。 本研究的科学价值基于对预测、表征和理解在接近 1500oC 温度下控制 RMPEA 机械响应的变形机制的迫切需求。先进的位错动力学介观建模、新颖的亚尺度机械测试和详细的微观结构表征的集成被用来收集急需的超高温拉伸和蠕变数据，以开发对近等原子、成分复杂的超高温变形的基本科学描述，多元合金。 参与约翰霍普金斯大学和加州大学圣塔芭芭拉分校的既定项目正在为代表性不足的高中生和本科生提供研究经验，拟议的本科生交流对于扩大 STEM 研究生的渠道具有真正的潜力，并且在STEM 领导者和榜样。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。