Composites Science and Technology最新文献

{"title":"Intrabead and interbead fracture analysis of large area additive manufactured polymer and polymer composites","authors":"Arief Yudhanto,&nbsp;Neshat Sayah,&nbsp;Douglas E. Smith","doi":"10.1016/j.compscitech.2025.111173","DOIUrl":"10.1016/j.compscitech.2025.111173","url":null,"abstract":"<div><div>Large-Area Additive Manufacturing (LAAM) has seen increased application in manufacturing meter-scale, polymeric composite structural parts, especially for tooling and fixturing. Unfortunately, LAAM introduces manufacturing-induced defects in printed composites, e.g., intrabead microvoids and poor interbead adhesion that are not otherwise seen when traditional manufacturing methods are used, causing degradation of mechanical and fracture properties. In this paper, the fracture behavior of neat acrylonitrile butadiene styrene (ABS) and short carbon fiber-reinforced ABS (CF/ABS) fabricated by LAAM is compared and analyzed by evaluating their energy release rate <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>I</mi><mi>c</mi></mrow></msub></math></span> and fracture mechanisms. A double cantilever beam with doublers (DCB-D) test for single-bead, double-bead, and multiple-bead configurations is developed by incorporating rigid doublers to reduce the compressive failure at the crack tip, allowing for the measurement of crack propagation. A new data reduction method for these configurations is derived to remove the doubler effect from the <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>I</mi><mi>c</mi></mrow></msub></math></span> calculation, producing ‘pure’ intrabead and interbead <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>I</mi><mi>c</mi></mrow></msub></math></span> values. We show that CF/ABS is more damage tolerant than ABS at the intrabead level, but less damage tolerant than ABS at the interbead level. The development of plastic ligaments in ABS helps dissipate additional strain energy, improving the overall energy release rate. The experimental fracture test approach developed here is expected to provide mechanistic insight into their damage tolerance capability, accelerating the qualification process of LAAM-produced polymer and polymer composites.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111173"},"PeriodicalIF":8.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interface-driven structural engineering of polypropylene carbonate-modified MgO composites for enhanced thermal conductivity","authors":"Ye-Ji Lee,&nbsp;Ji Young Park,&nbsp;Hong-Baek Cho,&nbsp;Yong-Ho Choa","doi":"10.1016/j.compscitech.2025.111177","DOIUrl":"10.1016/j.compscitech.2025.111177","url":null,"abstract":"<div><div>As electric vehicle (EV) batteries evolve toward higher energy densities, the demand for advanced thermal interface materials (TIMs) with high thermal conductivity (TC), superior mechanical strength, and anti-hydration properties becomes critical. TIMs must effectively dissipate heat while maintaining structural integrity under harsh thermal and humid conditions to ensure long-term reliability. In this study, we developed a high-performance epoxy composite incorporating thermally and chemically engineered magnesium oxide (MgO) fillers. The MgO was modified via thermal treatment and polypropylene carbonate (PPC) surface functionalization, forming a 365 nm hydrophobic coating layer while increasing the average grain size from 0.9 μm to 22 μm. This novel approach significantly mitigated Mg(OH)₂ formation after 120 h in deionized water at 50 °C.Furthermore, the interface engineering between PPC-modified MgO and epoxy enhanced phonon transport while reducing interfacial resistance, leading to a 65 % increase in tensile stress and a TC enhancement from 1.192 W/mK to 2.036 W/mK. By optimizing the high-density packaging (HDP) process, we achieved an unprecedented TC of 9.22 W/mK at a filler content of 75.1 vol%, surpassing conventional epoxy-based TIMs. This study demonstrates a synergistic strategy combining grain boundary engineering, interfacial optimization, and dense filler packing to develop next-generation TIMs.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111177"},"PeriodicalIF":8.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enabling multifunctional bio-based waterborne polyurethane through polyphenol-mediated assembly of zirconium phosphate nanoplatelets for patternable coating","authors":"Jiabo Shi ,&nbsp;Xiaoyi Wu ,&nbsp;Li Sheng ,&nbsp;Meng Chen ,&nbsp;Lei Shi ,&nbsp;Yi Zhang ,&nbsp;Jingyi Yang ,&nbsp;Shumin Mao ,&nbsp;Qiang Liu ,&nbsp;Zhijun Zhou","doi":"10.1016/j.compscitech.2025.111178","DOIUrl":"10.1016/j.compscitech.2025.111178","url":null,"abstract":"<div><div>Sustainable bio-based waterborne polyurethane (WPU) has been widely used in a wide range of industrial applications owing to its favorable environmental safety and excellent properties. However, achieving superior mechanical properties and favorable multifunctionalities in bio-based WPU remains a considerable challenge. In this work, we proposed a facile and effective interfacial engineering strategy which was synergistically enabled via phosphoric acid-assisted exfoliation and polyphenol-mediated assembly of zirconium phosphate nanoplatelets (ZrP NPs) to prepare multifunctional castor oil-based supramolecular WPU composites for patternable leather coating. Tunable ZrP based supramolecular assemblies with the weight ratio of TA to pZrP NPs of 2.0 wt.% and pH &gt; 5.0 were fabricated to manipulate the assembly of the WPU molecules. Active TA molecules bound on the interfaces of ZrP NPs can function as organic junctions through the formation of hydrogen-bonding interactions between the phenolic groups of TA molecules and the functional groups of WPU molecules. Benefiting from this hydrogen-bonding-driven co-assembly, the resultant supramolecular WPU composite films not only exhibited excellent transparency and reinforced mechanical strengths, thermal stability, and flame-retardant properties, but also possessed photoluminescent properties suitable for patternable leather coating. For example, the peak heat release rate (PHRR) was decreased from 389.45 kW/m² to 199.75 kW/m², and the total heat release (THR) was from 15.49 MJ/m² to 13.58 MJ/m². We envision that this study contributes to the development of sustainable multifunctional bio-based WPU coatings with significant potential for advanced applications in information encryption and displays, etc.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111178"},"PeriodicalIF":8.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Path planning for curved layer fused deposition modeling of continuous fiber reinforced structures with iso-void depth","authors":"Yuanzheng Zuo ,&nbsp;Hongtao Wang ,&nbsp;Ning Dai ,&nbsp;Kanghui Zhou ,&nbsp;Hongyu Chen ,&nbsp;Jun Liu","doi":"10.1016/j.compscitech.2025.111179","DOIUrl":"10.1016/j.compscitech.2025.111179","url":null,"abstract":"<div><div>At present, additive manufacturing of continuous fiber-reinforced composites (CFRCs) mainly adopts planar fiber layout. The development of multi-axis additive manufacturing systems provides unprecedented opportunities for the fabrication of composite structures with non-planar fiber layouts. This paper explores a multi-axis curved layer fused deposition modeling (CLFDM) process for CFRCs. Based on the drum-shaped deposition cross-section, a curved layer theoretical deposition model with equal void depth that satisfies uniform overlap is constructed. A path planning method for continuous fiber curved layer is proposed based on the theoretical deposition model. The accurate equal error step size calculation is performed under the change of the surface normal curvature and the curve curvature, achieving interference-free and equal error printing path discretization. Using 6-axis robot integrated with a dual-nozzle printing system, continuous fiber CLFDM is realized through its multiple degrees of freedom. Verified by computer simulation and physical printing experiments, the algorithm in this paper has considerable feasibility for various surface shapes, effectively enabling the manufacturing of continuous fiber curved layers with high fiber volume fraction. Comparative results of mechanical experiments show that the failure loads of the uniformly overlapped continuous fiber curved layers increased by 39.8 % and 89.2 %, and the stiffness increased by 47.8 % and 73.2 %, respectively. This provides new insights for the exploration of composite materials with complex curved fiber layouts.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111179"},"PeriodicalIF":8.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of hyperbranched polymer for advanced dental composites: Low shrinkage, high strength, and enhanced biocompatibility","authors":"Qiyue Zhang,&nbsp;Ibrahim Abdalla,&nbsp;Athar Hassan,&nbsp;Kangni Wang,&nbsp;Danyue Wang,&nbsp;Jia Zheng,&nbsp;Ruili Wang,&nbsp;Bin Sun,&nbsp;Xiaoze Jiang,&nbsp;Meifang Zhu","doi":"10.1016/j.compscitech.2025.111180","DOIUrl":"10.1016/j.compscitech.2025.111180","url":null,"abstract":"<div><div>Dental restorative composites (DRCs) commonly result in secondary caries due to high polymerization shrinkage (PS) after curing and low strength property after long-term performance. To address this, a hyperbranched polymer (HBP) molecule named HTH, possessing rigid phenyl, cross-linkable methacrylate, and inter/intra molecular interactable urethane was synthesized via a one-step Michael addition and esterification process using 1,1,1-trimethylolpropane with N, <em>N</em>-di (2-hydroxyethyl)-3-aminopropyl meth-acrylate and then modified the hydroxyl terminals with 2-{[(3-isocyanato-4-methylphenyl) carbamoyl]oxy}ethyl 2-methylprop-2-enoate (TDI-HEMA). The obtained HTH molecule was characterized, and effect of the incorporation of HBP molecules utilized as one co-monomer was explored on the properties of DRCs prepared by fixed 25 wt% organic matrix constitute of bisphenol A-glycidyl methacrylate (Bis-GMA)/tri(ethylene glycol) dimethacrylate (TEGDMA) (weight ratio 50:50, referred to as 5B5T) and 75 wt% micro- and nano-hybrid silica (SiO₂) fillers in details by Nuclear Magnetic Resonance spectroscopy (NMR), Fourier Transform Infrared Spectrometer (FT-IR), universal testing machine and density balance, etc. The measured results show: the HBP molecules, HTH, was synthesized successfully. The incorporation of HBP molecules reduces clearly the PS of DRCs, and the lowest PS of resultant DRCs could reach to 1.97 % by 20 wt% incorporation of HTH into 5B5T organic matrix and SiO₂ particle systems meanwhile their mechanical properties remained robust (compressive strength at 355.7 MPa) and achieved excellent biocompatibility. This construction of new type of HBP molecules bearing functional moieties similar Bis-GMA characteristics as co-monomer offers a promising light to develop novel commercialized DRCs with high strength property and low PS, seamlessly blending durability and functionality.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111180"},"PeriodicalIF":8.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving Modulus Matching and Enhanced Fatigue Resistance in Chloroprene Rubber/Trans-1, 4-poly(isoprene-co-butadiene) Nanocomposites: A Study on the Balance Between Crosslinking and Crystallinity in Dispersed Domains","authors":"Mingmei Jin,&nbsp;Xin Zong,&nbsp;Huarong Nie,&nbsp;Aihua He","doi":"10.1016/j.compscitech.2025.111175","DOIUrl":"10.1016/j.compscitech.2025.111175","url":null,"abstract":"<div><div>Improving the fatigue resistance and service life of chloroprene rubber (CR) nanocomposites through cost-effective rubber blending technology is a highly desirable goal for both academic research and industrial applications. However, critical challenges remain, particularly in optimizing the structure of the secondary component within CR matrix, which significantly affects mechanical durability. In this study, the incorporation of <em>trans</em>-1,4-poly(isoprene-<em>co</em>-butadiene) (TBIR) as a secondary component with CR was explored to produce CR/TBIR (90/10) vulcanizates with different TBIR domain structures, achieved by varying sulfur content. The results demonstrated that increasing sulfur content significantly enhanced crosslinking density in TBIR domains with a high proportion of disulfidic and polysulfidic bonds, and reduced TBIR crystallinity. Additionally, filler dispersion was significantly improved. At an optimal sulfur content (1.0 phr), the CR/TBIR-1.0 vulcanizate achieved an optimized TBIR domain structure with balanced crosslinking and crystallinity, leading to improved modulus matching between CR and TBIR domains. This resulted in superior mechanical properties, including enhanced tensile strength, elongation at break, abrasion resistance, and greatly improved tensile fatigue life, with damping properties remaining almost unchanged compared to CR vulcanizate. The optimized TBIR domains exhibited synergistic effects from adequate crosslinking density, moderate crystallinity, and improved filler dispersion through the whole matrix, facilitating modulus matching for superior stress transfer, inhibited crack initiation and enhanced fatigue resistance. Compared with conventional CR-based rubber blends, this study provides a novel structural optimization strategy, demonstrating that precisely tuning crosslinking density and crystallinity of TBIR domains offers a promising route to develop durable, high-performance elastomeric damping nanocomposites.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111175"},"PeriodicalIF":8.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cross-scale optimization of interfacial adhesion and thermal-mechanical performance in carbon fiber-reinforced polyimide composites through sizing agent evolution","authors":"Qiong Li ,&nbsp;Xiaohui Yang ,&nbsp;Xiong Li ,&nbsp;Nan Wang ,&nbsp;Xue Shen ,&nbsp;Na Song ,&nbsp;Tongle Xu ,&nbsp;Peng Ding","doi":"10.1016/j.compscitech.2025.111174","DOIUrl":"10.1016/j.compscitech.2025.111174","url":null,"abstract":"<div><div>The modification of carbon fibers with sizing agents, as an alternative to incorporating nanoparticles, has emerged as a practical strategy to enhance the interfacial adhesion and improve the thermal and mechanical properties of carbon fiber-reinforced thermoplastic polyimide (CF/TPI) composites. However, the lack of comprehensive understanding of the behavior and transformation of sizing agents during composite processing limits the performance enhancement of the composites. In this study, the interfacial mechanisms of sizing agents are systematically analyzed, distinguishing between chemical bonding and physical interaction pathways, while addressing the stages of wetting, molecular diffusion, and interfacial crosslinking. By optimizing the balance between chemical and physical interfacial mechanisms, significant improvements in stress distribution and filler-matrix compatibility are achieved. A quantitative relationship between sizing agent concentration and interfacial evolution was established, enabling precise control of the interface formation stages, including diffusion and crosslinking. The thermal conductivity of the optimized CF/TPI composites is 490% of that of PI. When used as a heat sink, it reduces the LED center temperature by 26 °C, while maintaining a tensile strength of 73 MPa and a retention rate of 69% at 200 °C. These results indicate that the precise control of the sizing process improved stress transfer across the interface, reduced microstructural defects, and contributed to enhanced thermal management and structural durability. This work provides a novel perspective on the dynamic role of sizing agents in composite development and lays the groundwork for advanced design strategies to maximize the performance of polymer composites.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111174"},"PeriodicalIF":8.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study on the thermo-mechanical dynamic response characteristics of unidirectional CF/PEEK composite laminates under high strain rates","authors":"Zhenbo Wu ,&nbsp;Tian Zhao ,&nbsp;Ziheng Qiu ,&nbsp;Boang Su ,&nbsp;Jingze Yi ,&nbsp;Ying Li","doi":"10.1016/j.compscitech.2025.111162","DOIUrl":"10.1016/j.compscitech.2025.111162","url":null,"abstract":"<div><div>This study systematically investigates the high-velocity impact behavior of CF/PEEK composite laminates along both the longitudinal and thickness directions using a combined theoretical, numerical, and experimental approach. Within the framework of the second law of thermodynamics, the inevitability of temperature rise and the irreversibility of stiffness degradation during impact processes were rigorously established, laying a fundamental foundation for investigating the thermo-mechanical response of semi-crystalline thermoplastic composites. The mechanisms and underlying causes of heat generation during impact were derived and validated, offering valuable insights into energy dissipation, damage evolution, and the interaction between thermal and mechanical phenomena. The finite element analysis (FEA), based on the proposed progressive damage-based heat generation theory, accurately captured both the temperature rise and stress distribution within the unidirectional CF/PEEK composite laminate specimens, demonstrating a strong correlation with the experimental data. The analysis revealed that impacts along the longitudinal direction primarily induce interfacial failure, fiber breakage, and shear cracking, whereas impacts along the transverse and thickness directions lead to inter-fiber failure (IFF), with cracks propagating at a 55° angle. This behavior is attributed to the anisotropic nature of unidirectional composites, which influences the shear stress distribution and governs the crack propagation direction. In both impact scenarios, extensive plastic deformation and brittle fracture were observed, further confirming the conversion of mechanical energy into thermal energy. These findings provide valuable insights for the structural design and optimization of composite materials subjected to extreme mechanical and thermal loading conditions.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111162"},"PeriodicalIF":8.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Curcumin encapsulated zeolitic imidazolate frameworks modified polyetheretherketone promotes osteogenic capacity through immunomodulation","authors":"Sihan Ma ,&nbsp;Heyi Gong ,&nbsp;Duo Sun ,&nbsp;Xin Fang ,&nbsp;Xiao Han ,&nbsp;Yue Liu ,&nbsp;Yadi Su ,&nbsp;Junqi Wang ,&nbsp;Yu Wang ,&nbsp;Jinghui Zhao","doi":"10.1016/j.compscitech.2025.111164","DOIUrl":"10.1016/j.compscitech.2025.111164","url":null,"abstract":"<div><div>Controlling the immune response and enhancing osteogenesis are essential for the long-term success of biomaterial implantation. Although polyetheretherketone (PEEK) is widely used in orthopedic implants, its inherent bioinertness and poor osteogenic capacity limit its use in clinical applications. In this study, curcumin (CCM) and zeolitic imidazolate frameworks-8 nanoparticles (ZIF-8 NPs) were introduced onto PEEK substrate to obtain the SPEEK-CCM@ZIF-8 (SPZC) system, which enhances osseointegration through early immunomodulation. SPEEK-CCM@ZIF-8 induces macrophage polarization towards M2 phenotype to reduce inflammation, promotes osteogenic differentiation capacity of bone marrow mesenchymal stem cells (BMSCs), and enhances the osseointegration and osteogenic capacity of PEEK implants. In vivo evaluation further confirmed the enhanced osteointegration effect of SPZC. Our results suggest that the CCM@ZIF-8 coating confers good osteogenic capacity to PEEK and that SPZC will have great potential as an implant.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111164"},"PeriodicalIF":8.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143735175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the effect of microstructural defects on the performance and fracture mechanism of adhesive single lap joints","authors":"Kai Pang ,&nbsp;Zewen Gu ,&nbsp;Jianqiao Ye ,&nbsp;Xiaonan Hou","doi":"10.1016/j.compscitech.2025.111166","DOIUrl":"10.1016/j.compscitech.2025.111166","url":null,"abstract":"<div><div>Adhesive joints offer advantages over traditional joining methods due to their lightweight nature, reduced stress concentration, and ease of manufacturing. Their mechanical performance is influenced by various factors, including defects, which can significantly affect the performance of the joints. However, research focusing on fracture mechanisms of adhesive joints influenced by defects at microscale is still limited. This study conducts both experimental and numerical investigations into the effect of microstructural defects on the performance and fracture mechanism of multi-type adhesive single lap joints (SLJ). The adherend materials are aluminium alloy (Al) and polyphthalamide (PPA), bonded with an epoxy adhesive. Mechanical properties of the adhesive, adherends and SLJs, obtained through experimental studies, are employed to calibrate the microparameters in Discrete Element Method (DEM) models for numerical analysis. The developed DEM models can predict the performance and capture the microstructural fracture mechanisms of multi-type SLJs, through realistically incorporating different types of microstructural defects, including the interfacial and adhesive defects. Finally, the influencing mechanisms of microstructural defects on the performance and fracture mechanisms of multi-type SLJs with different interfacial adhesion are investigated, including joint strength, microscale crack initiation, coalescence, and propagation.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"266 ","pages":"Article 111166"},"PeriodicalIF":8.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}