CAREER: Leveraging Plastic Deformation Mechanisms Interactions in Metallic Materials to Access Extraordinary Fatigue Strength.

职业：利用金属材料中的塑性变形机制相互作用来获得非凡的疲劳强度。

• 批准号: 2338346
• 负责人: jean-charles stinville
• 金额: $ 63.23万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-03-01 至 2029-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2338346&HistoricalAwards=false
• 关键词: CAREER; Leveraging; Plastic; Deformation; Mechanisms

NON-TECHNICAL SUMMARY:Metallic materials used in structural engineering are vital to a wide range of industries. However, many metals and alloys exhibit limited resistance to repeated loading (Fatigue), limiting their sustainability. Metallic materials under repeated loading localize deformation at the nanometer scale that ultimately leads to crack initiation and fracture. Pre-deformation under extreme temperatures is used in the present project to generate initial deformation states that hinder the localization of the deformation under repeated loading. First, the deformation behavior of metallic materials at the nanometer scale under extreme temperatures is determined. Then, through this fundamental understanding, deformation states from extreme temperature deformations that hinder the localization of the deformation when the material is subject to repeated loading are identified. This endeavor aims to equip current metals and alloys with the competitive edge and sustainability required to meet the ever-evolving needs of our society and advancing technology.TECHNICAL SUMMARY:The research initiative seeks to explore and identify the interactions of plastic deformation mechanisms in metallic materials. By focusing on beneficial interactions, remarkable fatigue strength in face-centered cubic materials can be achieved. This project will explore how plasticity localizes when various deformation mechanisms compete. State-of-the art in-situ characterization tools, adept at statistically and qualitatively determining plastic localization, is used to study the array of possible deformation mechanism interactions within metallic materials. Building on this knowledge, pre-deformation pathways at extreme temperatures are introduced to create initial plastic localization states that hinder cyclic irreversibility, a factor that governs material fracture under fatigue. By manipulating plastic localization at the nanoscale through deformation at extreme temperatures, the fatigue strength of structural metals is enhanced dramatically.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.

非技术摘要：结构工程中使用的金属材料对于广泛的行业至关重要。但是，许多金属和合金对重复负荷（疲劳）表现出有限的抵抗力，从而限制了它们的可持续性。重复负载下的金属材料在纳米尺度上局部变形，最终导致裂纹开始和断裂。在本项目中使用了在极端温度下的预染色，以生成初始变形，以阻碍重复负载下的变形定位。首先，确定了在极端温度下纳米尺度上金属材料的变形行为。然后，通过这种基本的理解，鉴定出材料受到重复载荷时，变形的变形呈现出极端温度变形的状态，这些变形阻碍了变形的定位。这项工作旨在为当前的金属和合金配备满足我们社会不断发展的需求并推进技术所需的竞争优势和可持续性。技术摘要：研究计划旨在探索和确定金属材料中塑性变形机制的相互作用。通过关注有益的相互作用，可以实现以面部为中心的立方材料的显着疲劳强度。该项目将探讨当各种变形机制竞争时，可塑性如何本地化。最先进的原位表征工具擅长于统计和定性地确定塑料定位，用于研究金属材料中可能的变形机制相互作用的数组。在这些知识的基础上，引入了极端温度下的预宣传途径，以创建最初的塑料定位，以阻碍环状不可逆性，这是控制疲劳下材料断裂的因素。通过在极端温度下通过变形来操纵塑料定位，结构金属的疲劳强度得到了显着增强。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛的影响审查标准通过评估来进行评估的。