The Mechanics of Debonding of Foam Core Sandwich Structure Under Cyclic Loading

循环加载下泡沫芯夹层结构脱粘机理

• 批准号: 0824827
• 负责人: Michael Santare
• 金额: $ 30万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0824827&HistoricalAwards=false
• 关键词: Mechanics; Debonding; Foam; Core; Sandwich

The mechanics of debonding of foam core sandwich structure under cyclic loadingAnette M. Karlsson, University of Delaware, Newark, DELeif A. Carlsson, Florida Atlantic University, Boca Raton, FLThis work aims to increase the understanding of fatigue in foam core sandwich structures. Foam core sandwich structures are composite structures consisting of two face sheets (typically aluminum or fiber reinforced polymer) and a cellular foamed polymer. Since sandwich structures are composed of widely dissimilar materials, they display peculiar and sometimes unexpected failure modes. Traditionally, the rate in which the cracks grow during cyclic (fatigue) loading is established by extensive (and therefore expensive) material testing. Theories describing damage (e.g., plastically dissipated energy) at the crack tip and the ensuing crack growth rate are developed in this research. These theories are quantified in numerical computer simulations. Only limited experimental investigations for determining important materials parameters will be needed as input to the computer code. The fatigue life predicted from the numerical simulations will be verified by full scale fatigue testing. Composite sandwich structures are light-weight structures with high strength, high impact resistance, and high resistance to corrosion along with low radar and acoustics signals. Current applications range from aircraft structures, to wind turbine blades, to ship hulls. Successful outcome of the research will result in a life prediction methodology relying on limited experimental input. This in turn will lead to reliable light-weight, and therefore more energy efficient, engineering structures. The research includes a significant educational component, including involving undergraduate students ? in particular from underrepresented groups ? in the research. The results will also be disseminated to K-12 students and science teachers through the University of Delaware, College of Engineering Outreach Programs.

泡沫夹层结构在循环载荷作用下的脱粘机理. Karlsson，特拉华州大学，纽瓦克，卡尔森，佛罗里达大西洋大学，博卡拉顿，佛罗里达州这项工作的目的是增加泡沫芯夹层结构疲劳的理解。 泡沫芯夹层结构是由两个面板（通常为铝或纤维增强聚合物）和多孔泡沫聚合物组成的复合结构。由于夹层结构是由非常不同的材料组成的，它们显示出独特的，有时是意想不到的失效模式。传统上，裂纹在循环（疲劳）加载期间的增长速率是通过广泛的（因此昂贵的）材料测试来确定的。描述损害的理论（例如，塑性耗散能）和随后的裂纹扩展速率。 这些理论在数值计算机模拟中被量化。只有有限的实验研究，以确定重要的材料参数将需要作为输入到计算机代码。 将通过全尺寸疲劳试验验证从数值模拟预测的疲劳寿命。 复合材料夹层结构是具有高强度、高抗冲击性和高耐腐蚀性的轻质结构，沿着低雷达和声学信号。 目前的应用范围从飞机结构，风力涡轮机叶片，船体。研究的成功结果将导致寿命预测方法依赖于有限的实验输入。 这反过来将导致可靠的轻质，因此更节能的工程结构。 这项研究包括一个重要的教育组成部分，包括涉及本科生？特别是代表性不足的群体？在研究中。 研究结果还将通过特拉华州大学工程学院推广计划传播给K-12学生和科学教师。