George Kampourakis , Fivos Simopoulos , George Karalis , Emmanouil Porfyrakis , Miron Krassas , Stavros Katsiaounis , Konstantinos Papagelis , Aaron Soul , Dimitrios G. Papageorgiou , Jitong Zhao , Marco Liebscher , Panos Chatzakos , Nikolaos Papadakis , Lazaros Tzounis
{"title":"三维打印增强i型断裂韧性和层间剪切强度的PLA/CF/CNT“微/纳米”多尺度纤维增强聚合物复合材料:热压后处理的影响","authors":"George Kampourakis , Fivos Simopoulos , George Karalis , Emmanouil Porfyrakis , Miron Krassas , Stavros Katsiaounis , Konstantinos Papagelis , Aaron Soul , Dimitrios G. Papageorgiou , Jitong Zhao , Marco Liebscher , Panos Chatzakos , Nikolaos Papadakis , Lazaros Tzounis","doi":"10.1016/j.compstruct.2025.119493","DOIUrl":null,"url":null,"abstract":"<div><div>Fused Filament Fabrication (FFF) three-dimensional (3D) printing empowers advanced and complex fiber-reinforced polymer (FRP) composites, but also possesses unavoidable high void content and limited interlaminar strength. Multi-scale reinforcement can effectively mitigate the out-of-plane performance limitations of 3D printed FRPs, by the incorporation of nano-additives at filament level. 3D printed continuous FRP composites of Polylactic acid (PLA)/ Carbon Fiber (CF)/ multi-walled carbon nanotubes (CNTs) with enhanced interlaminar strength and fracture toughness are reported for the first time. A custom roll-to-roll (R2R) line is developed for the impregnation of CF tows (3 K) with neat PLA and PLA/CNT nanocomposite polymer solutions, further employed as feedstock for single feed FFF 3D printing (3DP). PLA/CF and PLA/CF/CNT unidirectional (UD) 12-ply laminates ([0]<sub>12</sub>) are manufactured and thoroughly investigated through microstructural and physicochemical analyses, as well as mechanical testing, both for “as printed” (AP) and post-processed “thermally pressed” (TP) specimens. Namely, quasi-static flexural, short beam shear (SBS), Mode-I interlaminar fracture tests, Dynamic Mechanical Analysis (DMA) and fractography investigations elucidate the reinforcing mechanisms of CNTs in the 3DP CFRP laminates, i.e. via matrix stiffening, crack deflection, etc., significantly increasing the interlaminar shear strength (ILSS) and fracture toughness (G<sub>IC</sub>). The ultimate flexural strength (<em>σ<sub>UFS</sub></em>) is increased by 8.9 %, the storage modulus (<em>E′</em>) by 6.7 %, the ILSS by 30.1 % and the G<sub>IC</sub> by 32.0 % for the PLA/CF/CNT (TP) multi-scale composites. This work highlights a versatile approach for the effective utilization of nanoinclusions within the thermoplastic matrix of continuous 3DP FRPs showing enhanced mechanical performance.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"371 ","pages":"Article 119493"},"PeriodicalIF":7.1000,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Three-dimensional printing of PLA/CF/CNT “micro/nano” multi-scale fiber reinforced polymer composites with enhanced Mode-I fracture toughness and interlaminar shear strength: Effect of thermal press post treatment\",\"authors\":\"George Kampourakis , Fivos Simopoulos , George Karalis , Emmanouil Porfyrakis , Miron Krassas , Stavros Katsiaounis , Konstantinos Papagelis , Aaron Soul , Dimitrios G. Papageorgiou , Jitong Zhao , Marco Liebscher , Panos Chatzakos , Nikolaos Papadakis , Lazaros Tzounis\",\"doi\":\"10.1016/j.compstruct.2025.119493\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Fused Filament Fabrication (FFF) three-dimensional (3D) printing empowers advanced and complex fiber-reinforced polymer (FRP) composites, but also possesses unavoidable high void content and limited interlaminar strength. Multi-scale reinforcement can effectively mitigate the out-of-plane performance limitations of 3D printed FRPs, by the incorporation of nano-additives at filament level. 3D printed continuous FRP composites of Polylactic acid (PLA)/ Carbon Fiber (CF)/ multi-walled carbon nanotubes (CNTs) with enhanced interlaminar strength and fracture toughness are reported for the first time. A custom roll-to-roll (R2R) line is developed for the impregnation of CF tows (3 K) with neat PLA and PLA/CNT nanocomposite polymer solutions, further employed as feedstock for single feed FFF 3D printing (3DP). PLA/CF and PLA/CF/CNT unidirectional (UD) 12-ply laminates ([0]<sub>12</sub>) are manufactured and thoroughly investigated through microstructural and physicochemical analyses, as well as mechanical testing, both for “as printed” (AP) and post-processed “thermally pressed” (TP) specimens. Namely, quasi-static flexural, short beam shear (SBS), Mode-I interlaminar fracture tests, Dynamic Mechanical Analysis (DMA) and fractography investigations elucidate the reinforcing mechanisms of CNTs in the 3DP CFRP laminates, i.e. via matrix stiffening, crack deflection, etc., significantly increasing the interlaminar shear strength (ILSS) and fracture toughness (G<sub>IC</sub>). The ultimate flexural strength (<em>σ<sub>UFS</sub></em>) is increased by 8.9 %, the storage modulus (<em>E′</em>) by 6.7 %, the ILSS by 30.1 % and the G<sub>IC</sub> by 32.0 % for the PLA/CF/CNT (TP) multi-scale composites. This work highlights a versatile approach for the effective utilization of nanoinclusions within the thermoplastic matrix of continuous 3DP FRPs showing enhanced mechanical performance.</div></div>\",\"PeriodicalId\":281,\"journal\":{\"name\":\"Composite Structures\",\"volume\":\"371 \",\"pages\":\"Article 119493\"},\"PeriodicalIF\":7.1000,\"publicationDate\":\"2025-07-17\",\"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/S0263822325006580\",\"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/S0263822325006580","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}
Three-dimensional printing of PLA/CF/CNT “micro/nano” multi-scale fiber reinforced polymer composites with enhanced Mode-I fracture toughness and interlaminar shear strength: Effect of thermal press post treatment
Fused Filament Fabrication (FFF) three-dimensional (3D) printing empowers advanced and complex fiber-reinforced polymer (FRP) composites, but also possesses unavoidable high void content and limited interlaminar strength. Multi-scale reinforcement can effectively mitigate the out-of-plane performance limitations of 3D printed FRPs, by the incorporation of nano-additives at filament level. 3D printed continuous FRP composites of Polylactic acid (PLA)/ Carbon Fiber (CF)/ multi-walled carbon nanotubes (CNTs) with enhanced interlaminar strength and fracture toughness are reported for the first time. A custom roll-to-roll (R2R) line is developed for the impregnation of CF tows (3 K) with neat PLA and PLA/CNT nanocomposite polymer solutions, further employed as feedstock for single feed FFF 3D printing (3DP). PLA/CF and PLA/CF/CNT unidirectional (UD) 12-ply laminates ([0]12) are manufactured and thoroughly investigated through microstructural and physicochemical analyses, as well as mechanical testing, both for “as printed” (AP) and post-processed “thermally pressed” (TP) specimens. Namely, quasi-static flexural, short beam shear (SBS), Mode-I interlaminar fracture tests, Dynamic Mechanical Analysis (DMA) and fractography investigations elucidate the reinforcing mechanisms of CNTs in the 3DP CFRP laminates, i.e. via matrix stiffening, crack deflection, etc., significantly increasing the interlaminar shear strength (ILSS) and fracture toughness (GIC). The ultimate flexural strength (σUFS) is increased by 8.9 %, the storage modulus (E′) by 6.7 %, the ILSS by 30.1 % and the GIC by 32.0 % for the PLA/CF/CNT (TP) multi-scale composites. This work highlights a versatile approach for the effective utilization of nanoinclusions within the thermoplastic matrix of continuous 3DP FRPs showing enhanced mechanical performance.
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.