Understanding Mixed-Mode Fracture Mechanics in Additively Manufacturable Functionally Graded Microcellular Solids

了解可增材制造的功能梯度微孔固体中的混合模式断裂力学

基本信息

批准号：
2317406
负责人：
mirmilad mirsayar
金额：
$ 20.06万
依托单位：
Florida Institute of Technology
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：
2023-07-01 至 2026-06-30
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2317406&HistoricalAwards=false
关键词：
Understanding Mixed Mode Fracture Mechanics

项目摘要

The use of materials having cellular structures is rapidly growing in various engineering applications ranging from biomedical to aerospace, civil, and automotive industries. If designed accurately, cellular structures can be both high strength and light weight. In contrast to a traditional uniform pattern of cells across a structure, optimal designs usually require a non-uniform grading of cells, called a functionally graded structure. Recent advances in additive manufacturing and computational techniques have enabled researchers to precisely build functionally graded cellular structures with complex patterns. However, most available designs for optimized cell pattern configurations ignore the notches or cracks that can be formed in the printed components either during the fabrication process or due to excessive loads. The main goal of this research is to understand fracture mechanics near such critical areas in additively manufactured functionally graded cellular structures exposed to complex loading conditions. This fundamental understanding can then be integrated into next-generation design of engineered cellular structures with enhanced fracture resistance. The mathematical models and mechanics developed in this research will advance the fields of fracture mechanics, theoretical and computational mechanics, composite structures, and additive manufacturing. Additionally, through this project, graduate, undergraduate, and K-12 students will engage in several professional, educational, and outreach activities.This project aims to provide a greater understanding of fracture behavior in additively manufacturable functionally graded microcellular structures. The scientific objectives of this work are to i) demonstrate that different microcellular structures with different pattern functions can be successfully produced by additive manufacturing, ii) experimentally and computationally characterize their constitutive response, iii) develop a novel computationally efficient multiscale approach for prediction of their mixed mode fracture behavior, and iv) provide detailed information regarding how patterns and distributions of cells (i.e., topology and morphology) should be configured near the stress concentrations. To achieve these goals, different spatially pattered microcellular structures will be built by additive manufacturing to experimentally investigate their constitutive response, mixed-mode fracture toughness, and the crack propagation mechanism. A synergistic experimental/computational framework will be developed to predict and optimize fracture behavior by considering the material anisotropy induced from both the microcellular patterns and the printing orientation.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.

在生物医学到航空，民用和汽车行业的各种工程应用中，具有细胞结构的材料的使用正在迅速生长。如果精确设计，蜂窝结构可以是高强度和轻巧的重量。与跨结构的传统统一细胞模式相反，最佳设计通常需要分级的细胞分级，称为功能分级结构。添加剂制造和计算技术的最新进展使研究人员能够精确地构建具有复杂模式的功能分级的细胞结构。但是，用于优化单元格配置的大多数可用设计忽略了在制造过程中或由于过多的负载而在印刷组件中形成的凹口或裂纹。这项研究的主要目的是在此类关键区域附近理解裂缝机制，在功能分级的细胞结构中，暴露于复杂的负载条件下。然后可以将这种基本理解纳入具有增强裂缝抗性的工程细胞结构的下一代设计。这项研究中开发的数学模型和力学将推动断裂力学，理论和计算力学，复合结构和增材制造的领域。此外，通过这个项目，毕业生，本科生和K-12学生将从事几项专业，教育和外展活动。此项目旨在在可添加性制造的功能分级的微细胞结构中对破裂行为有更深入的了解。这项工作的科学目标是i）证明，具有不同模式功能的不同微细胞结构可以通过增材制造成功产生，ii）在实验和计算上表征其本构的响应，iii）开发出一种新颖的计算高效多尺度方法，以预测其混合模式骨折行为和详细信息的图案和iv的方式（IV），并提供了详细的信息（IV）（IV）（I. I. I. I. I. I. I. I. I. I. I. I. I. I. I.应力浓度。为了实现这些目标，将通过添加剂制造来建立不同的空间构图的微细胞结构，以实验研究其组成型响应，混合模式断裂韧性和裂纹传播机制。将开发一种协同的实验/计算框架，以通过考虑从微细胞模式和印刷方向引起的材料各向异性来预测和优化断裂行为。该奖项反映了NSF的法定任务，并通过使用该基金会的智力功能和广泛的影响来评估CRITERIA CRITERIA CRITERIA。