Catalyst Project: Microstructural Evolution and Constitutive Modeling of Creep and Elevated Temperature Quasi-Static Tensile Deformation in Additively Manufactured Grade 91 Alloy

催化剂项目：增材制造 91 级合金蠕变和高温准静态拉伸变形的微观结构演化和本构建模

• 批准号: 2200613
• 负责人: Abiodun Fasoro
• 金额: $ 15万
• 依托单位: Tennessee State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2200613&HistoricalAwards=false
• 关键词: Catalyst; Project; Microstructural; Evolution; Constitutive

Catalyst Projects provide support for Historically Black Colleges and Universities (HBCU) to work towards establishing research capacity of faculty to strengthen science, technology, engineering, and mathematics (STEM) undergraduate education and research. It is expected that the award will further the faculty member's research capability, improve research and teaching at the institution, and involve undergraduate students in research experiences. This award to Tennessee State University supports faculty and undergraduate research experiences in the development of phenomenological constitutive creep deformation models for Additively manufactured (AM) Grade 91 alloy. The proposed models will provide insights into the nature of the metallurgical processes taking place during hot deformation processes in AM Grade 91 alloy, which will ultimately determine the mechanical behavior of the material.Creep, the time-dependent deformation under statically applied load at high homologous temperature is detrimental, resulting in catastrophic failures and/or substantially reduced life of critical structural components in nuclear, aerospace, and microelectronic industries. Given that additive manufacturing (AM) is proliferating as a manufacturing technique across many industries, it is imperative to characterize creep mechanisms in AM ferritic steel alloys, a topic that has not been addressed in either the AM literature or the materials science literature. The goal of this research is to study the creep behavior of AM ferritic grade 91 steel alloys which are potential materials for high-temperature structural applications in the aerospace and nuclear energy industries. For this study, the test loads will range from 100 MPa to 300 MPa, while the test temperatures will range from 300⁰C – 700⁰C. The minimum creep rates obtained from the plots of creep strain against time provides a measure of the creep resistance. Creep testing will be complimented with microstructural study using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Rietveld refinement to gain insight into the fundamental mechanisms that control creep in AM ferritic grade 91 steels. The results of this study will aid the development of new generation of creep resistant superalloys, impacting the scholarly communities of AM and materials science, aerospace, and nuclear engineering industries.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.

催化剂项目为历史悠久的黑人学院和大学 (HBCU) 提供支持，致力于建立教师的研究能力，以加强科学、技术、工程和数学 (STEM) 本科教育和研究。预计该奖项将进一步促进教师的发展。田纳西州立大学的这一奖项支持教师和本科生在增材制造唯象本构蠕变变形模型开发方面的研究经验。 (AM) 91 级合金。所提出的模型将深入了解 AM 91 级合金热变形过程中发生的冶金过程的性质，这将最终决定材料的机械行为。蠕变，随时间变化的变形。鉴于增材制造 (AM) 行业中的关键结构部件在高同源温度下承受静态负载，会导致灾难性故障和/或关键结构部件的寿命大幅缩短。作为一种在许多行业中普及的制造技术，有必要表征增材制造铁素体钢合金的蠕变机制，这是增材制造文献或材料科学文献中尚未讨论的主题。本研究的目标是研究蠕变。 AM 铁素体 91 级钢合金的行为，该合金是航空航天和核能工业中高温结构应用的潜在材料。在本研究中，测试载荷范围为 100 MPa 至 300 MPa，而测试温度范围为 300⁰C – 700⁰C。从蠕变应变随时间变化的曲线图获得的最小蠕变速率可提供抗蠕变性的测量，并可使用光学显微镜 (OM)、扫描电子显微镜 (SEM) 进行微观结构研究。 )、能量色散光谱 (EDS) 和 Rietveld 精修，以深入了解控制 AM 铁素体 91 级蠕变的基本机制这项研究的结果将有助于新一代抗蠕变高温合金的开发，对增材制造和材料科学、航空航天和核工程行业的学术界产生影响。该奖项反映了 NSF 的法定使命，并被认为值得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。