Deformation Mechanisms Governing Torsional Fatigue Failure of Additively Manufactured Metals at High Temperatures

高温下增材制造金属扭转疲劳失效的变形机制

基本信息

批准号：
2055027
负责人：
Sanna Siddiqui
金额：
$ 14.89万
依托单位：
Florida Polytechnic University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2055027&HistoricalAwards=false
关键词：
Deformation Mechanisms Governing Torsional Fatigue

项目摘要

Recent advances in the 3D metal printing/additive manufacturing technology have allowed for the realization and rapid production of nickel-based metal superalloy components, extending their geometric design space and mechanical performance envelope. Nevertheless, there is a need to ensure that these additively manufactured components can withstand in-service operational conditions while meeting necessary functional requirements and durability. Torsional fatigue, characterized by cyclic twisting loads, is often an underlying cause for failure of nickel-based metal superalloys used in the extreme environments of rocket and jet engines, high performance automobiles, and pressure vessels. These extreme temperature environments are characterized by a complex loading state, in which the deformation mechanisms contributing to torsional fatigue failure remain unclear. This award supports fundamental research to delineate the principal deformation mechanisms at the microstructural level, which govern torsional fatigue failure of additively manufactured nickel-based metal superalloys subject to varying service conditions. This research will advance the current state of knowledge and maximize durability and viability of these alloys for in-service use, thereby maturing the current technology. Additionally, this study will broaden participation, outreach, and professional training of under-represented minority undergraduate and graduate students in STEM research spanning across the disciplines of mechanics, manufacturing, and materials science and engineering. Research outcomes will be used to establish enhanced educational curriculum/tools, including incorporation of a research project-based teaching and learning structure.The fundamental problem that this research addresses is capturing the micron scale to structural scale deformation response spectrum experienced by additively manufactured nickel superalloys under torsional fatigue loading conditions at ambient and high temperatures representing in-service component conditions. The role of temperature, varying cyclic torsional loadings, and additive manufacturing processing conditions and build orientation will be explored. A variety of material characterization techniques, such as energy dispersive spectroscopy, X-ray diffraction, and electron microscopy, will be used in conjunction with extensive fatigue testing to capture the driving microstructural mechanisms leading to torsional fatigue crack initiation and growth. It is anticipated that outcomes resulting from this study will reveal how torsional response of these alloys is impacted in terms of microstructural evolution under ambient and in-service operational conditions, potentially providing insights that will contribute to an understanding of their multiaxial fatigue response.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.

3D金属打印/添加剂制造技术的最新进展允许实现和快速生产基于镍的金属超合金组件，从而扩展了其几何设计空间和机械性能信封。然而，有必要确保这些加性制造的组件可以在满足必要的功能要求和耐用性的同时承受在服务的运营条件。扭转疲劳的特征是循环扭曲负荷，通常是在火箭和喷气发动机，高性能汽车和压力容器的极端环境中使用的基于镍的金属超合金的故障原因。这些极端温度环境的特征是复杂的载荷状态，其中导致扭转疲劳衰竭的变形机制尚不清楚。该奖项支持基本研究，以描述微观结构层的主要变形机制，该机制控制着添加性生产的基于镍的金属超合金团的扭转疲劳失败，但受到不同服务条件的影响。这项研究将提高当前知识状态，并最大程度地提高这些合金用于在职使用的耐用性和生存能力，从而使当前的技术融合。此外，这项研究将扩大跨越机械，制造业，材料科学与工程学科的STEM研究中代表性不足的本科生和研究生的参与，外展和专业培训。研究成果将用于建立增强的教育课程/工具，包括纳入基于项目的教学结构。本研究解决的基本问题正在捕获微米尺度到结构尺度变形响应响应谱，该响应谱是通过在环境和高温和高温下的扭转疲劳条件下添加性生产的镍超级合金来体验的镍超级合金。将探索温度，循环扭转载荷的作用以及添加剂制造处理条件和构建方向的作用。各种材料表征技术，例如能量分散光谱，X射线衍射和电子显微镜，将与广泛的疲劳测试结合使用，以捕获导致扭曲疲劳裂纹开始和生长的驱动显微结构机制。可以预料的是，这项研究产生的结果将揭示这些合金的扭转反应如何受到微观结构的进化影响，在环境和服务中的运营条件下，有可能提供洞察力，从而有助于理解其多用途疲劳响应的理解。这种奖项反映了NSF的法定任务和综述的依据，这是通过评估的范围来弥补的。