Nikolay V. Turbin , Kirill A. Shelkov , Nikolay O. Kononov , Ever J. Barbero
{"title":"利用离散损伤力学量化复合材料中的循环损伤","authors":"Nikolay V. Turbin , Kirill A. Shelkov , Nikolay O. Kononov , Ever J. Barbero","doi":"10.1016/j.compstruct.2024.118271","DOIUrl":null,"url":null,"abstract":"<div><p>A method for fatigue damage quantification in composite materials, based on experimental stiffness degradation data for composite laminates subjected to cyclic load is proposed. Discrete damage mechanics theory is used to calculate crack density vs. number of cycles from elastic moduli-reduction data obtained during fatigue experiments. The calculated crack density simplifies fatigue testing by diminishing the need for counting cracks during testing. Accurate results are achieved and reported. The defect-nucleation rate, which controls the fatigue damage rate, is also obtained from processing the modulus-reduction data. It is observed that the defect-nucleation rate has a small scatter and is independent of applied load magnitude. Furthermore, the onset of delamination observed in the experiments correlates very well with the onset of deviation between the predicted and experimental curves of elastic moduli-reduction versus accumulated crack density. An additional parameter, the defect-nucleation threshold, is here proposed to further characterize the fatigue performance of the composite material under stress-controlled fatigue loading, in contrast to thermal fatigue results from the literature. Furthermore, the difference in damage nucleation rate between strain-controlled and stress-controlled was observed and discussed.</p></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":null,"pages":null},"PeriodicalIF":6.3000,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Cyclic damage quantification in composite materials using discrete damage mechanics\",\"authors\":\"Nikolay V. Turbin , Kirill A. Shelkov , Nikolay O. Kononov , Ever J. Barbero\",\"doi\":\"10.1016/j.compstruct.2024.118271\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>A method for fatigue damage quantification in composite materials, based on experimental stiffness degradation data for composite laminates subjected to cyclic load is proposed. Discrete damage mechanics theory is used to calculate crack density vs. number of cycles from elastic moduli-reduction data obtained during fatigue experiments. The calculated crack density simplifies fatigue testing by diminishing the need for counting cracks during testing. Accurate results are achieved and reported. The defect-nucleation rate, which controls the fatigue damage rate, is also obtained from processing the modulus-reduction data. It is observed that the defect-nucleation rate has a small scatter and is independent of applied load magnitude. Furthermore, the onset of delamination observed in the experiments correlates very well with the onset of deviation between the predicted and experimental curves of elastic moduli-reduction versus accumulated crack density. An additional parameter, the defect-nucleation threshold, is here proposed to further characterize the fatigue performance of the composite material under stress-controlled fatigue loading, in contrast to thermal fatigue results from the literature. Furthermore, the difference in damage nucleation rate between strain-controlled and stress-controlled was observed and discussed.</p></div>\",\"PeriodicalId\":281,\"journal\":{\"name\":\"Composite Structures\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":6.3000,\"publicationDate\":\"2024-06-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Composite Structures\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0263822324003994\",\"RegionNum\":2,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATERIALS SCIENCE, COMPOSITES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Composite Structures","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0263822324003994","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, COMPOSITES","Score":null,"Total":0}
Cyclic damage quantification in composite materials using discrete damage mechanics
A method for fatigue damage quantification in composite materials, based on experimental stiffness degradation data for composite laminates subjected to cyclic load is proposed. Discrete damage mechanics theory is used to calculate crack density vs. number of cycles from elastic moduli-reduction data obtained during fatigue experiments. The calculated crack density simplifies fatigue testing by diminishing the need for counting cracks during testing. Accurate results are achieved and reported. The defect-nucleation rate, which controls the fatigue damage rate, is also obtained from processing the modulus-reduction data. It is observed that the defect-nucleation rate has a small scatter and is independent of applied load magnitude. Furthermore, the onset of delamination observed in the experiments correlates very well with the onset of deviation between the predicted and experimental curves of elastic moduli-reduction versus accumulated crack density. An additional parameter, the defect-nucleation threshold, is here proposed to further characterize the fatigue performance of the composite material under stress-controlled fatigue loading, in contrast to thermal fatigue results from the literature. Furthermore, the difference in damage nucleation rate between strain-controlled and stress-controlled was observed and discussed.
期刊介绍:
The past few decades have seen outstanding advances in the use of composite materials in structural applications. There can be little doubt that, within engineering circles, composites have revolutionised traditional design concepts and made possible an unparalleled range of new and exciting possibilities as viable materials for construction. Composite Structures, an International Journal, disseminates knowledge between users, manufacturers, designers and researchers involved in structures or structural components manufactured using composite materials.
The journal publishes papers which contribute to knowledge in the use of composite materials in engineering structures. Papers deal with design, research and development studies, experimental investigations, theoretical analysis and fabrication techniques relevant to the application of composites in load-bearing components for assemblies, ranging from individual components such as plates and shells to complete composite structures.