Understanding the Fundamental Mechanisms Governing Tensile Strength of High-Performance Small-Scale Carbon/Glass Fibers

了解控制高性能小型碳/玻璃纤维拉伸强度的基本机制

• 批准号: 1915948
• 负责人: Subramani Sockalingam
• 金额: $ 51.16万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1915948&HistoricalAwards=false
• 关键词: Understanding; Fundamental; Mechanisms; Governing; Tensile

This project is jointly funded by the Mechanics of Materials and Structures program and the Established Program to Stimulate Competitive Research (EPSCoR). High performance carbon and glass fibers are widely used as reinforcements in composite material systems for automotive, aerospace and defense applications. The tensile strength of commercial fibers is significantly less than its theoretical limits. The composite systems are often overdesigned, thus any increase in the fiber tensile strength can yield significant cost and weight savings. Modifications of fiber surface treatment (sizing) during manufacturing is a potential route to enhance the fiber strength. Single fiber tensile testing at millimeter-scale is typically used to characterize the effect of sizing on the fiber strength. However, the longitudinal tensile failure of a composite is governed by the fiber strength distribution and defects at microscale lengths. This award supports the fundamental research that overcomes current challenges in characterizing the tensile strength of the fibers at the microscale using experimental and data-driven computational methods. Besides the scientific understanding, this project will also provide a guiding template for the fiber manufacturing process through controlled surface treatment. A direct consequence of improving the tensile strength would be lightweight structures for applications in aerospace, automotive, and sports equipment sectors. As part of this project, a specific effort will also be aimed at recruiting graduate and undergraduate students from under-represented groups through the Society for Women Engineers at the University of South Carolina. Furthermore, the experimental setup developed in this research will be incorporated into a lab course for undergraduate students.A comprehensive understanding of the discrepancy between experimental tensile strength of commercial fibers and its theoretical limits has been elusive, and whether intrinsic fiber strength follows a Weibull statistical distribution remains an open question. This research aims to elucidate the fundamental mechanisms that govern the tensile strength of fibers at microscale gage lengths. Experimental and data-driven techniques will be employed to study the strength distribution of the fibers at microscales. Microscale gage lengths will be accessed by developing a novel in situ transverse loading experiment on single fibers under scanning electron microscope combined with micro-digital image correlation. Data-driven machine learning techniques will be applied to establish the scaling laws of strength. This research will provide new insights into the functional form of the survival probability and strength-controlling mechanisms in fibers influenced by fiber sizing. This new fundamental knowledge of processing (sizing)-structure (defect distribution)-property (tensile strength distribution) relationship at microscale lengths will enable the establishment of scaling laws for strength and will serve as a guide for fiber manufacturing process to enhance the fiber tensile strength.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.

该项目由材料和结构计划的机制以及刺激竞争研究的既定计划（EPSCOR）共同资助。高性能碳和玻璃纤维被广泛用作用于汽车，航空航天和防御应用的复合材料系统中的增援。商业纤维的拉伸强度大大低于其理论极限。复合系统通常过度设计，因此纤维抗拉强度的任何增加都可以节省大量成本和体重。制造过程中纤维表面处理（尺寸）的修饰是增强纤维强度的潜在途径。毫米级时的单纤维拉伸测试通常用于表征尺寸对纤维强度的影响。但是，复合材料的纵向拉伸失败受纤维强度分布和显微镜长度下的缺陷的控制。该奖项支持基本研究，该研究克服了使用实验和数据驱动的计算方法来表征微观纤维的拉伸强度的当前挑战。除了科学的理解外，该项目还将通过受控的表面处理为纤维制造过程提供指导模板。提高拉伸强度的直接后果将是用于航空，汽车和运动器材部门应用的轻量级结构。作为该项目的一部分，还将通过南卡罗来纳大学的女工程师协会招募来自代表性不足的团体的研究生和本科生。此外，这项研究中开发的实验设置将被纳入实验室课程中，以供本科生。对商业纤维的实验拉伸强度及其理论限制之间的差异，并且固有的纤维强度是否遵循Weibull统计分布仍然是一个悬而未决的问题。这项研究旨在阐明在微观量表长度上控制纤维的拉伸强度的基本机制。将采用实验和数据驱动的技术来研究显微镜纤维的强度分布。通过在扫描电子显微镜下与微数图像相关性结合的单个纤维上的单个横向载荷实验，将访问微观量表长度。数据驱动的机器学习技术将应用于建立强度缩放定律。这项研究将为受纤维尺寸影响的纤维中生存概率和强度控制机制的功能形式提供新的见解。这种新的关于处理（尺寸）结构（缺陷分布）的新基本知识 - 范围（拉伸强度分布）在显微镜长度上的关系将使能够建立缩放定律以实现力量，并将作为纤维制造过程的指南，以增强光纤牵引力。这些奖项通过评估NSF的授权及其授权的依据，并具有依据的授权，并具有良好的影响力。 标准。

项目成果

Sub-microscale speckle pattern creation on single carbon fibers for in-situ DIC experiments

用于原位 DIC 实验的单碳纤维上的亚微米级散斑图案创建

• DOI: 10.12783/asc36/35902
• 发表时间: 2021
• 期刊: Proceedings of the American Society for Composites Technical Conference
• 作者: Shah K, Yang G

Sub-microscale speckle pattern creation on single carbon fibers for scanning electron microscope-digital image correlation (SEM-DIC) experiments

• DOI: 10.1016/j.compositesa.2022.107331
• 发表时间: 2022-11
• 期刊: Composites Part A: Applied Science and Manufacturing
• 作者: Karan Shah;S. Sockalingam;H. O'Brien;G. Yang;Mohammad El Loubani;Dongkyu Lee;M. Sutton