褶皱缺陷对复合材料拉伸性能的影响规律:试验及数值模型
INFLUENCE OF WRINKLE ON THE TENSILE PROPERTIES OF COMPOSITE LAMINATES:EXPERIMENTS AND NUMERICAL MODEL
凌圣博 1姚启 1王乐蓬 1梅杰 1吴振2
作者信息
- 1. 西北工业大学航空学院,西安 710072
- 2. 西北工业大学航空学院,西安 710072;强度和结构完整性全国重点实验室,西安 710065
- 折叠
摘要
复合材料层合板在制造过程中会不可避免地产生各类缺陷,纤维褶皱缺陷是最为常见的缺陷形式之一.为了探究褶皱缺陷对复合材料层合板纤维方向拉伸性能的影响,制备了不含褶皱缺陷的高强玻璃纤维复合材料试验件,以及4种含有纤维褶皱缺陷的试验件.对制备的5组试验件进行了准静态拉伸试验,通过数字图像相关(DIC)技术测量了试验件的位移及应变.通过试验,研究了褶皱高宽比、褶皱角度对静强度及失效模式的影响.试验发现,含褶皱缺陷复合材料的静强度相比无缺陷复合材料降低40％以上,并且褶皱高宽比越大,或褶皱夹角越大,复合材料的静强度越低.与此同时,发现褶皱缺陷会显著改变复合材料的失效模式,使得原本单向纤维增强复合材料在纵向拉伸载荷作用下的炸裂失效变为纤维断裂失效和轻微的炸裂失效.此外,为了建立复合材料静强度与褶皱几何参数(高宽比和褶皱角度)之间的关系,使用多可信度机器学习算法构建了褶皱缺陷对复合材料静强度的影响模型,通过有限的试验数据预测了不同褶皱缺陷对复合材料静强度的影响规律.结果表明,构建的模型仅用极少的试验数据即可准确反应褶皱高宽比和褶皱角度对复合材料拉伸强度的影响,为研究含缺陷复合材料的力学性能提供了新方法.
Abstract
Defects are usually introduced into composite laminates during manufacturing process,and wrinkle of fiber is one of the most common defects in engineering.In order to investigate the influence of wrinkles on the mechanical properties of composite laminates along fiber direction,specimens without defects and specimens with 4 types of wrinkles are manufactured.Moreover,quasi-static tensile tests are carried out for the manufactured 5 groups of specimens,and the displacement and strain are measured by digital image correlation(DIC)technology.The influences of wrinkles on the static strength and failure pattern are studied through experimental tests.The results indicate that the static tensile strength along fiber direction of composite laminates with wrinkles is reduced by more than 40％compared to the static strength of composite laminates without wrinkle.Moreover,greater heigh-to-width ratio and bigger wrinkle angle will lead to smaller static tensile strength.At the same time,it can be found that the failure patterns of the composite laminates have been changed due to wrinkles,and breakage failure and blowout failure of fibers occur at the same time,while only blowout failure is present for the composite laminates without wrinkle defect.In addition,in order to describe the relationship between the static strength and geometry parameters of wrinkles(heigh-to-width ratio and angle),an influence model of wrinkle on static strength of composite laminates is built by employing a multi-fidelity machine learning algorithm,so the influence of different wrinkles on static strength can be predicted by using limited experimental data.The results indicate that the built model can accurately describe the influence of heigh-to-width ratio and angle of wrinkle on the tensile strength of composite laminates with a few of experimental data,therefore,the suggested model can be taken as a novel strategy for mechanical property investigation of composite laminates with defects.
关键词
复合材料层合板/褶皱缺陷/多可信度机器学习/失效模式/静强度Key words
composite laminates/wrinkle/multi-fidelity machine learning/failure pattern/static strength引用本文复制引用
出版年
2024
NETL
NSTL
万方数据