Effect of Alloying and Thermo-Mechanical Processing on the Deformation of Hexagonal Close-Packed Alloys

合金化和热机械加工对六方密排合金变形的影响

• 批准号: 1727237
• 负责人: K. Linga Murty
• 金额: $ 47.43万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-15 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1727237&HistoricalAwards=false
• 关键词: Effect; Alloying; Thermo; Mechanical; Processing

Hexagonal close-packed (HCP) metals such as titanium, magnesium and zirconium alloys are commonly used for structural applications in energy, transportation and biomedical technologies, and a thorough understanding of their mechanical integrity is central for their in-service sustainability. Correlating fine-scale structure of the alloys with their resistance to deformation at service temperatures will allow for new understanding of the mechanisms that control alloy performance, and can provide guidance for design of high-strength, durable components. This award supports fundamental scientific research to understand the role of alloy composition and structure on mechanical properties in zirconium-based alloys. The research brings experimental testing together with computational modeling to predict the behavior of these alloys based on the new knowledge of their composition, structure, and how these relate to properties and performance in service. The work will lead to new scientific understanding that can be applied to a number of important alloy systems, and will provide excellent educational opportunities for students participating in the research. Particular emphasis is placed on broadening participation in scientific research through engagement in K-12 outreach programs which will allow high school students the opportunity to participate in the research, along with undergraduate and graduate students.This research addresses the influence of thermo-mechanical treatment and alloying on creep anisotropy of zirconium alloys with emphasis on niobium addition and heat treatment. The addition of niobium as an alloying element has been shown to lend better performance and durability, and this research aims to understand the phenomena controlling this behavior. Creep anisotropies in these alloys will be investigated in the different regimes such as power-law and viscous creep, as well as at high stresses in the power-law breakdown region. Corresponding deformation microstructures will be characterized for a thorough understanding of the underlying creep mechanisms and the biaxial creep anisotropy. The knowledge derived from this research can be applied to understand the plastic deformation mechanisms of other HCP alloys at high temperatures, and can provide robust tools to predict dimensional changes in service. This research involves both experimental and modeling approaches, and the findings will be integrated into classroom teaching for training the next generation of Engineers.

六角形封闭式（HCP）金属（例如钛，镁和锆合金）通常用于能源，运输和生物医学技术的结构应用，并且对其机械完整性的彻底了解对于他们的服务可持续性至关重要。将合金的细尺度结构与在服务温度下对变形的抗性相关联，将使人们对控制合金性能的机制有了新的了解，并可以为设计高强度，耐用组件的设计提供指导。该奖项支持基本的科学研究，以了解合金组成和结构对锆基合金中机械性能的作用。该研究将实验测试与计算建模一起，以根据其组成，结构的新知识以及这些合金与服务中的属性和性能的关系来预测这些合金的行为。这项工作将导致新的科学理解，可以应用于许多重要的合金系统，并为参与研究的学生提供出色的教育机会。特别强调通过参与K-12外展计划扩大科学研究的参与，这将使高中生有机会与本科和研究生一起参与研究。这项研究探讨了热力学治疗的影响，并将其对蠕虫型氧化二氧化碳杂质的蠕动型和热治疗的影响。已证明将尼伯族的添加作为合金元素可以提高性能和耐用性，这项研究旨在了解控制这种行为的现象。这些合金中的蠕变各向异性将在诸如幂律和粘性蠕变等不同方向上进行研究，以及在幂律崩溃区域的高压力。相应的变形微结构将被表征，以透彻了解潜在的蠕变机制和双轴蠕变各向异性。从这项研究中得出的知识可以应用于高温下其他HCP合金的塑性变形机制，并可以提供强大的工具来预测服务的维度变化。这项研究既涉及实验方法和建模方法，结果将集成到课堂教学中，以培训下一代工程师。