Pub Date : 2024-09-17DOI: 10.1177/10996362241282954
PS Liu
The compressive behavior is one of the most fundamental mechanical properties for engineering materials. In this paper, the octahedral structure model of porous materials is used to evolve the mechanical analysis model under compressive loading for the porous composite materials, which are resulted from reticular metal foams with pore struts presenting multilayered structure. Starting from this analysis model, some fundamental mechanical relationships, including those of the safe load-bearing and overall strength, have been deduced for these porous composite materials. The compressive strength has been characterized for the porous composite body, corresponding to the overall failure caused by the prior breakage of the strut core and by the prior breakage of the strut shell, respectively. The nickel foam products manufactured on the production line of enterprise were used to make porous composite materials by coating the pore struts with epoxy resin, and the metal foam composite material was obtained with the composite pore-struts of metal/resin multilayered structure. Using this porous composite material for compression experiments, it is found that the experimental data match well with the mathematical relationship from the present theoretical model. The results verify the feasibility of this analysis model and the practicality of the relevant mathematical relationship.
{"title":"Fundamental mechanical relations of open-cell metal foam composite materials with reticular porous structure","authors":"PS Liu","doi":"10.1177/10996362241282954","DOIUrl":"https://doi.org/10.1177/10996362241282954","url":null,"abstract":"The compressive behavior is one of the most fundamental mechanical properties for engineering materials. In this paper, the octahedral structure model of porous materials is used to evolve the mechanical analysis model under compressive loading for the porous composite materials, which are resulted from reticular metal foams with pore struts presenting multilayered structure. Starting from this analysis model, some fundamental mechanical relationships, including those of the safe load-bearing and overall strength, have been deduced for these porous composite materials. The compressive strength has been characterized for the porous composite body, corresponding to the overall failure caused by the prior breakage of the strut core and by the prior breakage of the strut shell, respectively. The nickel foam products manufactured on the production line of enterprise were used to make porous composite materials by coating the pore struts with epoxy resin, and the metal foam composite material was obtained with the composite pore-struts of metal/resin multilayered structure. Using this porous composite material for compression experiments, it is found that the experimental data match well with the mathematical relationship from the present theoretical model. The results verify the feasibility of this analysis model and the practicality of the relevant mathematical relationship.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"210 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142260996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-17DOI: 10.1177/10996362241285011
Seyed Mahdi Atifeh, Mohammad Sedighi, Ramin Hashemi
Nowadays, composite sheets have been increasingly developed in various applications due to their better corrosion and wear resistance as well as higher strength and formability. Of these, Al/SS bilayer sheets have been used in the food and automotive industries due to their favorable performance and low cost. In this research, the bonding strength of Al1050/AISI304 bilayer sheets fabricated by cold roll bonding has been investigated experimentally. At first, the design of the experiment was carried out using the surface response method, taking into account the thickness of the layers and the rolling reduction ratio, bilayer sheet using the rolling bonding method. In this research, for the first time, the bonding strength of Al/SS bilayer sheets fabricated by cold rolling bonding method and its optimization have been investigated. The bond strength was extracted using T peeling test. Then, using the linear regression method, a mathematical-experimental relationship was presented to obtain the peeling strength in terms of the thickness of the layers and the reduction ratio. The obtained results were analyzed using statistical methods and the table of coefficients, the table of residuals and the analysis of variance table of the data related to bond strength were presented and the adequacy of the presented model was examined. The results showed that by reducing the reduction ratio in the cold rolling process and also reducing the initial thickness of the sheets, the bond strength of the bilayer sheet has decreased. Then, bond strength optimization was done as a function of input parameters. The results indicated that the bonding strength reached its maximum level at the thickness of the aluminum layer = 2 mm, the thickness of the stainless-steel layer = 1.3 mm and reduction = 75%.
{"title":"Bond strength empirical-mathematical equation and optimization of Al1050/AISI304 bilayer sheets fabricated by cold roll bonding method","authors":"Seyed Mahdi Atifeh, Mohammad Sedighi, Ramin Hashemi","doi":"10.1177/10996362241285011","DOIUrl":"https://doi.org/10.1177/10996362241285011","url":null,"abstract":"Nowadays, composite sheets have been increasingly developed in various applications due to their better corrosion and wear resistance as well as higher strength and formability. Of these, Al/SS bilayer sheets have been used in the food and automotive industries due to their favorable performance and low cost. In this research, the bonding strength of Al1050/AISI304 bilayer sheets fabricated by cold roll bonding has been investigated experimentally. At first, the design of the experiment was carried out using the surface response method, taking into account the thickness of the layers and the rolling reduction ratio, bilayer sheet using the rolling bonding method. In this research, for the first time, the bonding strength of Al/SS bilayer sheets fabricated by cold rolling bonding method and its optimization have been investigated. The bond strength was extracted using T peeling test. Then, using the linear regression method, a mathematical-experimental relationship was presented to obtain the peeling strength in terms of the thickness of the layers and the reduction ratio. The obtained results were analyzed using statistical methods and the table of coefficients, the table of residuals and the analysis of variance table of the data related to bond strength were presented and the adequacy of the presented model was examined. The results showed that by reducing the reduction ratio in the cold rolling process and also reducing the initial thickness of the sheets, the bond strength of the bilayer sheet has decreased. Then, bond strength optimization was done as a function of input parameters. The results indicated that the bonding strength reached its maximum level at the thickness of the aluminum layer = 2 mm, the thickness of the stainless-steel layer = 1.3 mm and reduction = 75%.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"61 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142261090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1177/10996362241285001
Hassan Ejaz, Sameer Khalid, M. Babar Saeed, Abdullah Nadeem
This study examined the flexural and impact responses of sandwich panels with honeycomb core and hybrid fiber-reinforced composite skins. The influence of laminate composition and thickness on these mechanical properties was investigated. Carbon, glass, and Kevlar fibers were employed in various combinations to fabricate the composite skins. The findings revealed a general trend of increasing flexural strength, modulus, and toughness with rising laminate thickness. However, the laminate configuration exerted a significant influence. Configurations with a higher carbon fiber content exhibited superior strength but reduced strain (ductility). Conversely, configurations incorporating glass or Kevlar fibers demonstrated enhanced ductility at the expense of strength. Overall, configurations utilizing dry carbon fabric skins achieved the highest flexural strength and toughness, while the combination of carbon and glass fibers offered a desirable compromise between strength and ductility. Regarding impact resistance, configurations with solely carbon fibers initially showed the best performance. However, configurations employing a combination of carbon and glass fibers exhibited a noteworthy increase in impact strength with increasing laminate thickness. This observation suggests that the inclusion of glass fibers alongside carbon fibers provides a well-balanced combination of strength and energy absorption capability.
{"title":"Flexural and impact response of sandwich panels with Nomex honeycomb core and hybrid fiber composite skins","authors":"Hassan Ejaz, Sameer Khalid, M. Babar Saeed, Abdullah Nadeem","doi":"10.1177/10996362241285001","DOIUrl":"https://doi.org/10.1177/10996362241285001","url":null,"abstract":"This study examined the flexural and impact responses of sandwich panels with honeycomb core and hybrid fiber-reinforced composite skins. The influence of laminate composition and thickness on these mechanical properties was investigated. Carbon, glass, and Kevlar fibers were employed in various combinations to fabricate the composite skins. The findings revealed a general trend of increasing flexural strength, modulus, and toughness with rising laminate thickness. However, the laminate configuration exerted a significant influence. Configurations with a higher carbon fiber content exhibited superior strength but reduced strain (ductility). Conversely, configurations incorporating glass or Kevlar fibers demonstrated enhanced ductility at the expense of strength. Overall, configurations utilizing dry carbon fabric skins achieved the highest flexural strength and toughness, while the combination of carbon and glass fibers offered a desirable compromise between strength and ductility. Regarding impact resistance, configurations with solely carbon fibers initially showed the best performance. However, configurations employing a combination of carbon and glass fibers exhibited a noteworthy increase in impact strength with increasing laminate thickness. This observation suggests that the inclusion of glass fibers alongside carbon fibers provides a well-balanced combination of strength and energy absorption capability.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"29 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142261091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-09DOI: 10.1177/10996362241282854
Serhat Osmanoglu, Christian Mittelstedt
This paper deals with the analytical and numerical global buckling analysis of rectangular sandwich plates utilized AlSi10 Mg in both facesheets and lattice cores. In this study, six different strut-based lattice core models are designed. Additionally, the buckling resistance of lattice panels is compared with a typical honeycomb panel. Analytical studies were carried out using Kirchoff plate theory (CLPT), first-order shear deformation theory (FSDT) coded on MATLAB and finite element (FE) analyses in Abaqus. In the theoretical approaches, the Navier solution is derived for sandwich plates with simply supported boundary conditions at all edges. In the FE analyses, validated homogenized lattice structures models were used to avoid excessive numbers of elements and to save computational time. The parametric effects of side-to-thickness ratio, and different designed core cells on global buckling responses are investigated. As a result of comparing the analytical results with the FE model, a good agreement is obtained, and it is found that analytical buckling analyses FSDT can be used within certain size limits for the global buckling analysis of lattice core sandwich structures.
{"title":"Global buckling response of sandwich panels with additively manufactured lattice cores","authors":"Serhat Osmanoglu, Christian Mittelstedt","doi":"10.1177/10996362241282854","DOIUrl":"https://doi.org/10.1177/10996362241282854","url":null,"abstract":"This paper deals with the analytical and numerical global buckling analysis of rectangular sandwich plates utilized AlSi10 Mg in both facesheets and lattice cores. In this study, six different strut-based lattice core models are designed. Additionally, the buckling resistance of lattice panels is compared with a typical honeycomb panel. Analytical studies were carried out using Kirchoff plate theory (CLPT), first-order shear deformation theory (FSDT) coded on MATLAB and finite element (FE) analyses in Abaqus. In the theoretical approaches, the Navier solution is derived for sandwich plates with simply supported boundary conditions at all edges. In the FE analyses, validated homogenized lattice structures models were used to avoid excessive numbers of elements and to save computational time. The parametric effects of side-to-thickness ratio, and different designed core cells on global buckling responses are investigated. As a result of comparing the analytical results with the FE model, a good agreement is obtained, and it is found that analytical buckling analyses FSDT can be used within certain size limits for the global buckling analysis of lattice core sandwich structures.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"2 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is a need to develop innovative protective shield structures to withstand extreme loads, such as impact and blast loading. Sandwich structures that absorb significant kinetic energy as strain energy through plastic deformation offer superior protection. This study conducts a numerical analysis of structured sandwich protective structures subjected to airblast loads using finite element modeling. First, an experimental result from the literature was used to validate and verify finite element models of an architected sandwich structure modeled in Abaqus/Explicit software. Second, parametric studies were conducted on sandwich structures with additional layers of insert plates and newly proposed core topologies for viable shield protection against airblast loading. The finite element analysis results indicated that, under the same impulsive load, the control sandwich panel exhibited higher kinetic energy, demanding a proportionally larger internal energy. Conversely, sandwich structures with additional inner core insert plates dissipated the imposed kinetic energy more efficiently, due to the inelastic plastic deformation of the proposed core configurations. Moreover, the energy absorption capacity and back sheet displacement time-history were significantly improved by dense-hierarchical inner core configurations. Additionally, the parametric study analysis showed that increasing the number of insert plates and designing the core topology of cellular walls to be redundant, dense-hierarchical, and braced against buckling significantly reduced core collapse mechanisms such as folding, buckling, and crushing. However, despite these benefits, a reversed effect on the areal specific energy absorption index was observed.
{"title":"Numerical study on structured sandwich panels exposed to spherical air explosions","authors":"Solomon Abebe Derseh, Tesfaye Alemu Mohammed, Girum Urgessa","doi":"10.1177/10996362241282863","DOIUrl":"https://doi.org/10.1177/10996362241282863","url":null,"abstract":"There is a need to develop innovative protective shield structures to withstand extreme loads, such as impact and blast loading. Sandwich structures that absorb significant kinetic energy as strain energy through plastic deformation offer superior protection. This study conducts a numerical analysis of structured sandwich protective structures subjected to airblast loads using finite element modeling. First, an experimental result from the literature was used to validate and verify finite element models of an architected sandwich structure modeled in Abaqus/Explicit software. Second, parametric studies were conducted on sandwich structures with additional layers of insert plates and newly proposed core topologies for viable shield protection against airblast loading. The finite element analysis results indicated that, under the same impulsive load, the control sandwich panel exhibited higher kinetic energy, demanding a proportionally larger internal energy. Conversely, sandwich structures with additional inner core insert plates dissipated the imposed kinetic energy more efficiently, due to the inelastic plastic deformation of the proposed core configurations. Moreover, the energy absorption capacity and back sheet displacement time-history were significantly improved by dense-hierarchical inner core configurations. Additionally, the parametric study analysis showed that increasing the number of insert plates and designing the core topology of cellular walls to be redundant, dense-hierarchical, and braced against buckling significantly reduced core collapse mechanisms such as folding, buckling, and crushing. However, despite these benefits, a reversed effect on the areal specific energy absorption index was observed.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"35 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-07DOI: 10.1177/10996362241282864
Nathaphon Buddhacosa, Matthew Ibrahim, Chananya Charnsethikul, Parichamon Santivongskul, Akbar Khatibi, Raj Das, Everson Kandare
Integrating scrap rubber particles as fillers into polymer matrix composites offers a cost effective and environmentally sustainable pathway to manage tyre waste through the creation of value-added products. This research explores the low-velocity impact (LVI) response and compression after impact (CAI) properties of rubberised foam-core glass fibre-reinforced epoxy (GFRE) sandwich composites. Syntactic foam cores integrated with rubber particles were manufactured using vacuum-assisted resin transfer moulding (VARTM). The compression properties of rubberised foam core, vital for resisting impact damage during LVI, were examined. Results show more than 40% reduction in compression strength and modulus of the syntactic foam upon the inclusion of 33 wt.% rubber particles. The LVI response and residual compression properties of rubberised foam-core composites were also evaluated. Rubberised foam cores caused a marginal reduction in the peak impact force and led to approximately 60% reduction in the delamination area. The pre-impact compression strength was unaffected by rubber particles within the core as the GFRE face sheets carried most of the compression load. Post-impact compression strength was slightly higher in rubberised foam-core composites due to reduced delamination. Digital Image Correlation (DIC) analysis tracking of the strain evolution during CAI experiments revealed the stress-raising effect of the impact damaged region. This study showcases sustainable scrap tyre management through the inclusion of rubber particles into foam-core composites without substantially reducing in-plane compression properties before or after low-velocity impact.
{"title":"Impact response and compression-after-impact properties of foam-core sandwich composites incorporating scrap tyre rubber particles","authors":"Nathaphon Buddhacosa, Matthew Ibrahim, Chananya Charnsethikul, Parichamon Santivongskul, Akbar Khatibi, Raj Das, Everson Kandare","doi":"10.1177/10996362241282864","DOIUrl":"https://doi.org/10.1177/10996362241282864","url":null,"abstract":"Integrating scrap rubber particles as fillers into polymer matrix composites offers a cost effective and environmentally sustainable pathway to manage tyre waste through the creation of value-added products. This research explores the low-velocity impact (LVI) response and compression after impact (CAI) properties of rubberised foam-core glass fibre-reinforced epoxy (GFRE) sandwich composites. Syntactic foam cores integrated with rubber particles were manufactured using vacuum-assisted resin transfer moulding (VARTM). The compression properties of rubberised foam core, vital for resisting impact damage during LVI, were examined. Results show more than 40% reduction in compression strength and modulus of the syntactic foam upon the inclusion of 33 wt.% rubber particles. The LVI response and residual compression properties of rubberised foam-core composites were also evaluated. Rubberised foam cores caused a marginal reduction in the peak impact force and led to approximately 60% reduction in the delamination area. The pre-impact compression strength was unaffected by rubber particles within the core as the GFRE face sheets carried most of the compression load. Post-impact compression strength was slightly higher in rubberised foam-core composites due to reduced delamination. Digital Image Correlation (DIC) analysis tracking of the strain evolution during CAI experiments revealed the stress-raising effect of the impact damaged region. This study showcases sustainable scrap tyre management through the inclusion of rubber particles into foam-core composites without substantially reducing in-plane compression properties before or after low-velocity impact.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"8 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-07DOI: 10.1177/10996362241282826
Majid Mokhtari
Composite sandwich structures, which are widely employed in engineering structures, require a multitude of inserts. In certain instances, the necessity for a specialized insert arises from the unique characteristics of a particular application. In applications such as weather radar radomes, double-curved sandwich panels should be designed with electromagnetic (EM) transparency as a primary objective. The use of metal inserts should be restricted to the absolute minimum. Given the limitations of using metal materials to protect against EM radiation and the need to enhance the load-bearing capacity of the joint against pull-out loads, a composite insert has developed as an innovative solution. In this study, a composite insert of a double-curved sandwich dome has been developed using silica nanoparticles, and its mechanical strength against pull-out load has been evaluated through both experimental and numerical analysis. The strength results obtained have been compared with analytical estimates. Additionally, the buckling of the double-curved sandwich dome against a wind speed of 220 km/h has been investigated numerically. The critical buckling load for wind loading for the full-scale sandwich radome was estimated to be 16,303 N. According to the numerical results obtained with the Abaqus finite element (FE) software, the maximum pull-out force applied to the connection area is approximately 10.7 kN. A parametric study of geometric variables and experimental results showed that it is possible to achieve a stronger composite insert (by 1 wt % nano silica particles) by 20.7% lighter and 102.65% more bearing capacity.
{"title":"Development of an electromagnetic compatible composite-insert embedded in a double-curved sandwich panel","authors":"Majid Mokhtari","doi":"10.1177/10996362241282826","DOIUrl":"https://doi.org/10.1177/10996362241282826","url":null,"abstract":"Composite sandwich structures, which are widely employed in engineering structures, require a multitude of inserts. In certain instances, the necessity for a specialized insert arises from the unique characteristics of a particular application. In applications such as weather radar radomes, double-curved sandwich panels should be designed with electromagnetic (EM) transparency as a primary objective. The use of metal inserts should be restricted to the absolute minimum. Given the limitations of using metal materials to protect against EM radiation and the need to enhance the load-bearing capacity of the joint against pull-out loads, a composite insert has developed as an innovative solution. In this study, a composite insert of a double-curved sandwich dome has been developed using silica nanoparticles, and its mechanical strength against pull-out load has been evaluated through both experimental and numerical analysis. The strength results obtained have been compared with analytical estimates. Additionally, the buckling of the double-curved sandwich dome against a wind speed of 220 km/h has been investigated numerically. The critical buckling load for wind loading for the full-scale sandwich radome was estimated to be 16,303 N. According to the numerical results obtained with the Abaqus finite element (FE) software, the maximum pull-out force applied to the connection area is approximately 10.7 kN. A parametric study of geometric variables and experimental results showed that it is possible to achieve a stronger composite insert (by 1 wt % nano silica particles) by 20.7% lighter and 102.65% more bearing capacity.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"68 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.1177/10996362241278215
Donghai Du, Xiaoyan Liang, Weijie Li, Yalei Wang, Zhongwei Zhang
Variable stiffness Carbon/Carbon (C/C) honeycomb can be designed to exhibit varying stiffness based on the structural load gradient, facilitating a high degree of alignment between structural performance and function. The elimination of mass redundancy and achievement of extreme light-weighting confer promising applications in the aerospace sector. However, the universal preparation approach for variable stiffness honeycomb faces challenges related to material mass redundancy and susceptibility to cracking at the bonds. Consequently, addressing the integrated forming issues associated with variable stiffness honeycomb becomes urgent. In this study, firstly, the conventional honeycomb densification method and the CVI domain-limited reactor design approach for integrated forming of variable-stiffness honeycombs are discussed. Subsequently, a multi-physics field coupling model for C/C honeycomb forming is developed, and its accuracy is validated through honeycomb forming experiments. The influence of three key process parameters, gas residence time, temperature, and pressure, on the quality of honeycomb forming were explored. Following the influence laws, the study applies specific process parameters to the three distinct regions of the reactor. Through this meticulously regulated process, the final variable stiffness honeycomb attains a 17.6 % reduction in weight compared to a constant density honeycomb of the same volume.
{"title":"A novel integrated forming strategy based on chemical vapor infiltration for C/C honeycomb with variable stiffness","authors":"Donghai Du, Xiaoyan Liang, Weijie Li, Yalei Wang, Zhongwei Zhang","doi":"10.1177/10996362241278215","DOIUrl":"https://doi.org/10.1177/10996362241278215","url":null,"abstract":"Variable stiffness Carbon/Carbon (C/C) honeycomb can be designed to exhibit varying stiffness based on the structural load gradient, facilitating a high degree of alignment between structural performance and function. The elimination of mass redundancy and achievement of extreme light-weighting confer promising applications in the aerospace sector. However, the universal preparation approach for variable stiffness honeycomb faces challenges related to material mass redundancy and susceptibility to cracking at the bonds. Consequently, addressing the integrated forming issues associated with variable stiffness honeycomb becomes urgent. In this study, firstly, the conventional honeycomb densification method and the CVI domain-limited reactor design approach for integrated forming of variable-stiffness honeycombs are discussed. Subsequently, a multi-physics field coupling model for C/C honeycomb forming is developed, and its accuracy is validated through honeycomb forming experiments. The influence of three key process parameters, gas residence time, temperature, and pressure, on the quality of honeycomb forming were explored. Following the influence laws, the study applies specific process parameters to the three distinct regions of the reactor. Through this meticulously regulated process, the final variable stiffness honeycomb attains a 17.6 % reduction in weight compared to a constant density honeycomb of the same volume.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"38 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.1177/10996362241278222
Do-Hyeon Jin, Dong-Jin Park, Jung-Ryul Lee, Joon-Mo Ahn
This paper presents a novel approach to addressing electromagnetic property variations in 3D printed structures using additive manufacturing (AM). Utilizing continuous fiber 3D printing, the focus is on designing and fabricating a square convex surface multilayer radar absorbing structure (RAS) tailored for obliquely incident electromagnetic (EM) waves. Variations in complex permittivity due to structural shape-influenced changes in nozzle paths in AM-fabricated 3D printed structures are observed. To counter this, a ‘Process Permittivity Correction Method’ is developed, enhancing design and fabrication accuracy. Before optimizing each structure of the RAS, the process permittivity, which varies according to the structural shape and the set nozzle paths, was applied in the design. The optimized RAS, considering both TE and TM modes at a 60° incident angle, showed a high correlation between the trends of interpreted and measured absorption performance. This approach effectively corrects electromagnetic property variations in 3D printed structures, ensuring consistency between design and manufacturing while maintaining EM properties and absorption performance.
本文介绍了一种利用增材制造（AM）解决三维打印结构中电磁特性变化的新方法。利用连续纤维三维打印技术，重点设计和制造一种专为斜入射电磁波（EM）量身定制的方形凸面多层雷达吸收结构（RAS）。在调幅制造的三维打印结构中，观察到由于结构形状影响喷嘴路径变化而导致的复介电常数变化。为解决这一问题，我们开发了一种 "工艺介电常数校正方法"，以提高设计和制造精度。在优化 RAS 的每个结构之前，在设计中应用了根据结构形状和设定喷嘴路径而变化的工艺介电常数。优化后的 RAS 同时考虑了 60° 入射角下的 TE 和 TM 模式，显示出解读趋势与测量吸收性能之间的高度相关性。这种方法可有效纠正 3D 打印结构中的电磁特性变化，确保设计与制造的一致性，同时保持电磁特性和吸收性能。
{"title":"Design and verification of the square convex surface multilayer radar absorbing structure based on additive manufacturing","authors":"Do-Hyeon Jin, Dong-Jin Park, Jung-Ryul Lee, Joon-Mo Ahn","doi":"10.1177/10996362241278222","DOIUrl":"https://doi.org/10.1177/10996362241278222","url":null,"abstract":"This paper presents a novel approach to addressing electromagnetic property variations in 3D printed structures using additive manufacturing (AM). Utilizing continuous fiber 3D printing, the focus is on designing and fabricating a square convex surface multilayer radar absorbing structure (RAS) tailored for obliquely incident electromagnetic (EM) waves. Variations in complex permittivity due to structural shape-influenced changes in nozzle paths in AM-fabricated 3D printed structures are observed. To counter this, a ‘Process Permittivity Correction Method’ is developed, enhancing design and fabrication accuracy. Before optimizing each structure of the RAS, the process permittivity, which varies according to the structural shape and the set nozzle paths, was applied in the design. The optimized RAS, considering both TE and TM modes at a 60° incident angle, showed a high correlation between the trends of interpreted and measured absorption performance. This approach effectively corrects electromagnetic property variations in 3D printed structures, ensuring consistency between design and manufacturing while maintaining EM properties and absorption performance.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"6 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1177/10996362241280020
Yazdan Akbari Birgani, Ali Ghorbanpour Arani, Zahra Khoddami Maraghi
In this paper, the buckling analysis of a five-layer laminated nanocomposite resting on a Kerr foundation is presented. In order to describe the non-continuous behavior of composite plate through its thickness, the displacement field is determined using the Refined Zigzag Theory (RZT). Additionally, the constitutive relations of piezo electromagnetic isotropic materials, orthotropic composites, and Functionally Graded Porous Materials (FGPMs) are presented. With respect to Bi- and Uniaxial loading in the nanoplate, the Hamilton’s principle is utilized to derive the equation of motion of this nanoplate. To study the small-scale effect in nanoplates, both Nonlocal Eringen Theory and Nonlocal Strain Gradient Theory (NSGT) are employed to account for nonlocal effects. Finally, the coupled equations of motion are solved using the Differential Quadrature Method (DQM). This paper introduces the newly used Kerr foundation and its effect on the buckling analysis. It also investigates the influence of plate dimensions, piezo electromagnetic terms, boundary conditions, and loading on the dimensionless critical buckling load.
{"title":"Nonlocal buckling analysis of five-layer laminated nanocomposites on kerr foundation: A refined zigzag theory approach","authors":"Yazdan Akbari Birgani, Ali Ghorbanpour Arani, Zahra Khoddami Maraghi","doi":"10.1177/10996362241280020","DOIUrl":"https://doi.org/10.1177/10996362241280020","url":null,"abstract":"In this paper, the buckling analysis of a five-layer laminated nanocomposite resting on a Kerr foundation is presented. In order to describe the non-continuous behavior of composite plate through its thickness, the displacement field is determined using the Refined Zigzag Theory (RZT). Additionally, the constitutive relations of piezo electromagnetic isotropic materials, orthotropic composites, and Functionally Graded Porous Materials (FGPMs) are presented. With respect to Bi- and Uniaxial loading in the nanoplate, the Hamilton’s principle is utilized to derive the equation of motion of this nanoplate. To study the small-scale effect in nanoplates, both Nonlocal Eringen Theory and Nonlocal Strain Gradient Theory (NSGT) are employed to account for nonlocal effects. Finally, the coupled equations of motion are solved using the Differential Quadrature Method (DQM). This paper introduces the newly used Kerr foundation and its effect on the buckling analysis. It also investigates the influence of plate dimensions, piezo electromagnetic terms, boundary conditions, and loading on the dimensionless critical buckling load.","PeriodicalId":17215,"journal":{"name":"Journal of Sandwich Structures & Materials","volume":"23 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142188187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：