{"title":"Extension of the crack equivalent method applied to mode II fracture of thermoplastic composites bonded joints using the ENF test","authors":"","doi":"10.1016/j.compstruct.2024.118687","DOIUrl":null,"url":null,"abstract":"<div><div>Thermoplastic based composites (TPC) have emerged as a new generation of eco-friendly materials with tougher matrices capable of overcoming the major weaknesses of the thermoset counterparts related with poor resistance to delamination and recycling difficulties. Although TPC materials present low surface energy, adhesive bonding is still effective when the requirements for fusion bonding procedures are not met. Recent advances in adhesive technology have unveiled two-part acrylic adhesive specifically designed for low energy surfaces, characteristic of TPC materials. In this work, unidirectional carbon-reinforced polyamide 6 (CF/PA6) bonded joint was characterized under pure mode II loading using end-notched flexure (ENF) test. The experimental fracture tests revealed unstable crack propagation and a data reduction scheme based on the equivalent crack concept was developed to obtain the strain energy release rate distribution along the crack front for the specimen’s length beyond the actuator central loading point. The proposed procedure was successfully validated using a finite element analysis including a cohesive zone modelling and applied to the experimental results. The obtained <em>Resistance</em>-curves showed that this adhesive is capable to provide a significant bonding resistance in pure mode II loading even in low energy surfaces characteristic of TPC materials.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":null,"pages":null},"PeriodicalIF":6.3000,"publicationDate":"2024-11-02","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/S0263822324008158","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}
引用次数: 0
Abstract
Thermoplastic based composites (TPC) have emerged as a new generation of eco-friendly materials with tougher matrices capable of overcoming the major weaknesses of the thermoset counterparts related with poor resistance to delamination and recycling difficulties. Although TPC materials present low surface energy, adhesive bonding is still effective when the requirements for fusion bonding procedures are not met. Recent advances in adhesive technology have unveiled two-part acrylic adhesive specifically designed for low energy surfaces, characteristic of TPC materials. In this work, unidirectional carbon-reinforced polyamide 6 (CF/PA6) bonded joint was characterized under pure mode II loading using end-notched flexure (ENF) test. The experimental fracture tests revealed unstable crack propagation and a data reduction scheme based on the equivalent crack concept was developed to obtain the strain energy release rate distribution along the crack front for the specimen’s length beyond the actuator central loading point. The proposed procedure was successfully validated using a finite element analysis including a cohesive zone modelling and applied to the experimental results. The obtained Resistance-curves showed that this adhesive is capable to provide a significant bonding resistance in pure mode II loading even in low energy surfaces characteristic of TPC materials.
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.