Thermal protection systems (TPS) are employed on space vehicles to protect against the heat fluxes faced upon re-entry to the Earth’s atmosphere. This work reports a method of 3D printing composite materials for TPS to reduce the time and cost associated with hand layup production methods. A phenolic resin system was tested to determine char yield, viscosity, cure behavior and cure evolutions. A commercial 3D printer was modified to move along two additional axes to accommodate the complex curves of typical heat shields on space vehicles. This technique can be scaled to produce full-sized TPS for industrial applications.
太空飞行器采用热保护系统（TPS）来抵御重返地球大气层时所面临的热通量。这项工作报告了一种用于 TPS 的 3D 打印复合材料的方法，以减少与手糊生产方法相关的时间和成本。对一种酚醛树脂系统进行了测试，以确定炭产量、粘度、固化行为和固化演化。对商用三维打印机进行了改装，使其能够沿另外两个轴移动，以适应航天器上典型隔热罩的复杂曲线。该技术可用于生产工业应用的全尺寸 TPS。
{"title":"Five-Axis Additive Manufacturing of a Thermoset Composite Formulation for Thermal Protection Systems","authors":"A. Kennedy, Z. McNulty, Steven Nutt","doi":"10.33599/sj.v60no4.04","DOIUrl":"https://doi.org/10.33599/sj.v60no4.04","url":null,"abstract":"Thermal protection systems (TPS) are employed on space vehicles to protect against the heat fluxes faced upon re-entry to the Earth’s atmosphere. This work reports a method of 3D printing composite materials for TPS to reduce the time and cost associated with hand layup production methods. A phenolic resin system was tested to determine char yield, viscosity, cure behavior and cure evolutions. A commercial 3D printer was modified to move along two additional axes to accommodate the complex curves of typical heat shields on space vehicles. This technique can be scaled to produce full-sized TPS for industrial applications.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141701785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samiul Alam, Md Tareq Hassan, Joshua Merrell, Juhyeong Lee
Additive manufacturing (AM) or 3D-printing of fiber-reinforced composites (FRCs) has garnered significant interests for its versatility in creating intricate parts and rapid prototyping due to cost-effectiveness. Although short fiber-reinforced thermoplastic composites are challenging to manufacture, their mechanical properties can be easily tailored by adjusting fiber type, orientation, and volume fraction. However, void formation during printing is a key issue, impacting mechanical properties and facilitating water ingression, affecting long-term durability. This work studies water diffusion characteristics and the associated hydro-aging of 3D-printed short carbon fiber (SCF)/acrylonitrile butadiene styrene (ABS) composites with controlled water diffusion. Effects of material type (ABS and SCF/ABS), 3D-printing path (horizontal and vertical filament orientation), and diffusion surface (uni-directional and bi-directional diffusion) on water diffusion coefficient and maximum water absorption level are characterized to ensure the long-term durability of 3D-printed ABS and SCF/ABS composites. Baseline representative volume element-based finite element (RVE-FE) diffusion models were developed based on micro-computed tomography (micro-CT) image analysis to understand water diffusion characteristics. This work proves that the SCF/ABS composite is more resistive to hydro-aging than neat ABS due to the SCFs’ hydrophobic nature. SCF/ABS composites, while providing distinct advantages over pure ABS in terms of mechanical properties, could also be more effective against water environments.
{"title":"Comparative Analysis of Water-Induced Response in 3D-Printed SCF/ABS Composites under Controlled Diffusion","authors":"Samiul Alam, Md Tareq Hassan, Joshua Merrell, Juhyeong Lee","doi":"10.33599/sj.v60no4.02","DOIUrl":"https://doi.org/10.33599/sj.v60no4.02","url":null,"abstract":"Additive manufacturing (AM) or 3D-printing of fiber-reinforced composites (FRCs) has garnered significant interests for its versatility in creating intricate parts and rapid prototyping due to cost-effectiveness. Although short fiber-reinforced thermoplastic composites are challenging to manufacture, their mechanical properties can be easily tailored by adjusting fiber type, orientation, and volume fraction. However, void formation during printing is a key issue, impacting mechanical properties and facilitating water ingression, affecting long-term durability. This work studies water diffusion characteristics and the associated hydro-aging of 3D-printed short carbon fiber (SCF)/acrylonitrile butadiene styrene (ABS) composites with controlled water diffusion. Effects of material type (ABS and SCF/ABS), 3D-printing path (horizontal and vertical filament orientation), and diffusion surface (uni-directional and bi-directional diffusion) on water diffusion coefficient and maximum water absorption level are characterized to ensure the long-term durability of 3D-printed ABS and SCF/ABS composites. Baseline representative volume element-based finite element (RVE-FE) diffusion models were developed based on micro-computed tomography (micro-CT) image analysis to understand water diffusion characteristics. This work proves that the SCF/ABS composite is more resistive to hydro-aging than neat ABS due to the SCFs’ hydrophobic nature. SCF/ABS composites, while providing distinct advantages over pure ABS in terms of mechanical properties, could also be more effective against water environments.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141699411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Honeycomb (HC) has been used in energy absorption applications due to its high stiffness and low density. Metallic HC are used for energy absorption applications, however, these metallic structures can be challenging to manufacture if complex geometric features designed to improve energy absorption are used, which motivates the use of additive manufacturing (AM). Metal AM methods include powder bed fusion (PBF) and direct energy deposition (DED). In addition to capital equipment cost, these processes possess challenges that include a required inert environment, powder handling, final part porosity, residual stresses, and nonuniform surface finish. These concerns can be alleviated through the use of polymer AM, however, polymeric parts exhibit brittle failure and have a lower stiffness than metallic HC structures. In this study, a low-cost 3D polymer printing method, stereolithography (SLA), is combined with a conventional electroplating process to fabricate a metal-plastic composite HC structure with energy absorption capability much greater than of a plastic HC structures of the same nominal volume. SLA parts have a smooth surface, so that the surface finish is at least as uniform after electroplating as the SLA part. The energy absorption characteristics of the electroplated HC is studied to determine how these energy absorbing materials can be manufactured at reduced cost. Our study confirms that the metal-plastic composite HC increases both the crush strain range and the mean crush stress of these samples, resulting in metal-plastic composite HC structures with substantially increased energy absorption. This study also examines how buckling initiators (BIs), or diamond shaped holes located at 50, 75, and 100% of the height of the hexagonal cell vertices, can influence energy absorption performance. This study shows that it is feasible to fabricate electroplated HCs, using an SLA preform, to achieve a substantial increase in energy absorption over using SLA alone.
蜂窝（HC）具有刚度高、密度低的特点，因此被广泛应用于能量吸收领域。金属蜂窝可用于能量吸收应用，但是，如果使用复杂的几何特征来改善能量吸收，这些金属结构的制造可能具有挑战性，这就促使人们使用增材制造（AM）。金属增材制造方法包括粉末床熔融（PBF）和直接能量沉积（DED）。除了资本设备成本外，这些工艺还面临着一些挑战，包括所需的惰性环境、粉末处理、最终零件的多孔性、残余应力和不均匀的表面光洁度。然而，与金属 HC 结构相比，聚合物零件的失效较脆，刚度较低。在本研究中，低成本三维聚合物打印方法--立体光刻（SLA）--与传统电镀工艺相结合，制造出了金属塑料复合 HC 结构，其能量吸收能力远高于相同标称体积的塑料 HC 结构。SLA 零件表面光滑，因此电镀后的表面光洁度至少与 SLA 零件一样均匀。我们对电镀碳氢化合物的能量吸收特性进行了研究，以确定如何以更低的成本制造这些能量吸收材料。我们的研究证实，金属塑料复合 HC 增加了这些样品的挤压应变范围和平均挤压应力，从而使金属塑料复合 HC 结构的能量吸收能力大幅提高。本研究还探讨了屈曲启动器（BI）或位于六边形单元顶点高度 50、75 和 100%处的菱形孔如何影响能量吸收性能。该研究表明，使用 SLA 预型件制造电镀 HC 是可行的，与单独使用 SLA 相比，电镀 HC 的能量吸收能力大幅提高。
{"title":"Electroplating Additively Manufactured Honeycomb Structures to Increase Energy Absorption Under Quasi-Static Crush","authors":"Colleen M Murray, Sean Wise, Norman M. Wereley","doi":"10.33599/sj.v60no4.05","DOIUrl":"https://doi.org/10.33599/sj.v60no4.05","url":null,"abstract":"Honeycomb (HC) has been used in energy absorption applications due to its high stiffness and low density. Metallic HC are used for energy absorption applications, however, these metallic structures can be challenging to manufacture if complex geometric features designed to improve energy absorption are used, which motivates the use of additive manufacturing (AM). Metal AM methods include powder bed fusion (PBF) and direct energy deposition (DED). In addition to capital equipment cost, these processes possess challenges that include a required inert environment, powder handling, final part porosity, residual stresses, and nonuniform surface finish. These concerns can be alleviated through the use of polymer AM, however, polymeric parts exhibit brittle failure and have a lower stiffness than metallic HC structures. In this study, a low-cost 3D polymer printing method, stereolithography (SLA), is combined with a conventional electroplating process to fabricate a metal-plastic composite HC structure with energy absorption capability much greater than of a plastic HC structures of the same nominal volume. SLA parts have a smooth surface, so that the surface finish is at least as uniform after electroplating as the SLA part. The energy absorption characteristics of the electroplated HC is studied to determine how these energy absorbing materials can be manufactured at reduced cost. Our study confirms that the metal-plastic composite HC increases both the crush strain range and the mean crush stress of these samples, resulting in metal-plastic composite HC structures with substantially increased energy absorption. This study also examines how buckling initiators (BIs), or diamond shaped holes located at 50, 75, and 100% of the height of the hexagonal cell vertices, can influence energy absorption performance. This study shows that it is feasible to fabricate electroplated HCs, using an SLA preform, to achieve a substantial increase in energy absorption over using SLA alone.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141701644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Since its creation, the plastic extrusion screw has been applied to several manufacturing processes. One of the newest applications of this technology has been 3D printing. Using an extrusion screw allows higher extrusion rates than direct drive extruders using a filament spool. This paper further develops the design by decreasing the standard screw length by removing the metering zone and replacing it with a gear pump. This allows for a smaller machine footprint. Extruders are susceptible to surging (inconsistency of the melt pressure and flow rate). Adding a gear pump to the extruder increases flow consistency at the nozzle, but this adds additional length and weight. With the addition of this gear pump-based metering device, the metering section of the screw is redundant and can be removed. By creating a shorter extruder, manufacturers can increase the flow rate without increasing machine size. The proposed extruder design is validated through flow testing and analysis of voids in the bead cross-section with image processing. By showing that a consistent bead can be produced without a metering section in the extruder, this extruder design can print parts with a wide range of materials.
塑料挤出螺杆自诞生以来，已应用于多种制造工艺。这项技术的最新应用之一是 3D 打印。与使用丝轴的直接驱动挤出机相比，使用挤出螺杆可以获得更高的挤出率。本文通过取消计量区并用齿轮泵取而代之来减少标准螺杆长度，从而进一步发展了这一设计。这使得挤压机的占地面积更小。挤出机很容易出现浪涌（熔体压力和流速不一致）。在挤出机上加装齿轮泵可提高喷嘴处流量的一致性，但会增加长度和重量。增加这种齿轮泵计量装置后，螺杆的计量部分就多余了，可以去掉。通过缩短挤出机的长度，制造商可以在不增加机器尺寸的情况下提高流速。拟议的挤出机设计通过流量测试和图像处理分析珠子横截面上的空隙进行了验证。结果表明，在挤出机中没有计量部分也能生产出一致的珠子，因此这种挤出机设计可以打印各种材料的部件。
{"title":"Design of Extruder with Metering Section Removed and Replaced with Gear Pump for Machine Space Savings in Large Format Additive Manufacturing","authors":"E. Piatt, Vysakh Venugopal, Sam Anand","doi":"10.33599/sj.v60no4.01","DOIUrl":"https://doi.org/10.33599/sj.v60no4.01","url":null,"abstract":"Since its creation, the plastic extrusion screw has been applied to several manufacturing processes. One of the newest applications of this technology has been 3D printing. Using an extrusion screw allows higher extrusion rates than direct drive extruders using a filament spool. This paper further develops the design by decreasing the standard screw length by removing the metering zone and replacing it with a gear pump. This allows for a smaller machine footprint. Extruders are susceptible to surging (inconsistency of the melt pressure and flow rate). Adding a gear pump to the extruder increases flow consistency at the nozzle, but this adds additional length and weight. With the addition of this gear pump-based metering device, the metering section of the screw is redundant and can be removed. By creating a shorter extruder, manufacturers can increase the flow rate without increasing machine size. The proposed extruder design is validated through flow testing and analysis of voids in the bead cross-section with image processing. By showing that a consistent bead can be produced without a metering section in the extruder, this extruder design can print parts with a wide range of materials.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141693164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As the aerospace industry continues to adopt additively manufactured (AM) parts for flight hardware, process simulation becomes more attractive to improve the manufacturing process by understanding how process parameters affect part quality and performance. Process simulation can also be used to predict and prevent build failures before the printing process. The powder bed fusion process of Ti-6Al-4V material is modeled using commercial finite element software to simulate the selective laser melting process. The thermal history is obtained from transient heat transfer analysis. Both the inherent strain approach and a sequential thermal-mechanical approach are employed to predict residual stress and part distortion. A National Agency for Finite Element Methods and Standards (NAFEMS) benchmark problem is presented as a numerical example. It is a thin wall structure with geometry features that can lead to part defects due to thermal distortion. It is shown that both analysis approaches are able to capture the thin-member bridging behavior, stepping behavior, and general distortion contour plot as those published by NAFEMS.
{"title":"Additive Manufacturing Process Simulation of Laser Powder Bed Fusion and Benchmarks","authors":"M. Ghabbour, X. Qu, J. Rome","doi":"10.33599/sj.v60no4.03","DOIUrl":"https://doi.org/10.33599/sj.v60no4.03","url":null,"abstract":"As the aerospace industry continues to adopt additively manufactured (AM) parts for flight hardware, process simulation becomes more attractive to improve the manufacturing process by understanding how process parameters affect part quality and performance. Process simulation can also be used to predict and prevent build failures before the printing process. The powder bed fusion process of Ti-6Al-4V material is modeled using commercial finite element software to simulate the selective laser melting process. The thermal history is obtained from transient heat transfer analysis. Both the inherent strain approach and a sequential thermal-mechanical approach are employed to predict residual stress and part distortion. A National Agency for Finite Element Methods and Standards (NAFEMS) benchmark problem is presented as a numerical example. It is a thin wall structure with geometry features that can lead to part defects due to thermal distortion. It is shown that both analysis approaches are able to capture the thin-member bridging behavior, stepping behavior, and general distortion contour plot as those published by NAFEMS.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141700906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Norman Wereley, Jungjin Park, John Howard, Matthew DeMay, Avi Edery
This article examines amorphous glass-based foams as lightweight core materials for crash-resistant structures that offer tailorable energy absorption capabilities. Hollow glass microspheres (HGMs) of different densities are layered using dry powder print- ing (DPP), an additive manufacturing process, and subsequently sintered to consolidate these microspheres into a cellular foam structure. The tuning of energy absorption is achieved in these foams by layering hollow microspheres with different densities and different thickness ratios of the layers. The mechanical response to quasi-static uniax- ial compression of the bilayer foams is also investigated. Bilayer samples a distinctive two-step stress-strain profile that includes first and second plateau stress, as opposed to a single constant density which does not. The strain at which the second plateau occurs can be tuned by adjusting the thickness ratio of the two layers. The resulting tailorable stress-strain profile demonstrates tailorable energy absorption. Tailorability is found to be more significant if the density values of each layer differ greatly. For comparison, bilayer samples are fabricated using epoxy at the interface instead of the co-sintering process. Epoxy-bonded samples show a different mechanical response from the co-sintered sample with a different stress-strain profile. Designing the bilayer foams enables tailoring of the stress-strain profile, so that energy-absorption requirements can be met for a specific impact condition. The implementation of these materials for energy absorption, crashworthiness, and buoyancy applications will be discussed.
{"title":"Tailorable Energy Absorbing Cellular Materials via Sintering of Dry Powder Printed Hollow Glass Microspheres","authors":"Norman Wereley, Jungjin Park, John Howard, Matthew DeMay, Avi Edery","doi":"10.33599/sj.v60no3.04","DOIUrl":"https://doi.org/10.33599/sj.v60no3.04","url":null,"abstract":"This article examines amorphous glass-based foams as lightweight core materials for crash-resistant structures that offer tailorable energy absorption capabilities. Hollow glass microspheres (HGMs) of different densities are layered using dry powder print- ing (DPP), an additive manufacturing process, and subsequently sintered to consolidate these microspheres into a cellular foam structure. The tuning of energy absorption is achieved in these foams by layering hollow microspheres with different densities and different thickness ratios of the layers. The mechanical response to quasi-static uniax- ial compression of the bilayer foams is also investigated. Bilayer samples a distinctive two-step stress-strain profile that includes first and second plateau stress, as opposed to a single constant density which does not. The strain at which the second plateau occurs can be tuned by adjusting the thickness ratio of the two layers. The resulting tailorable stress-strain profile demonstrates tailorable energy absorption. Tailorability is found to be more significant if the density values of each layer differ greatly. For comparison, bilayer samples are fabricated using epoxy at the interface instead of the co-sintering process. Epoxy-bonded samples show a different mechanical response from the co-sintered sample with a different stress-strain profile. Designing the bilayer foams enables tailoring of the stress-strain profile, so that energy-absorption requirements can be met for a specific impact condition. The implementation of these materials for energy absorption, crashworthiness, and buoyancy applications will be discussed.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141030745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reduced order models facilitate initial design space investigations and enable assessing the benefits of compliant structures utilized for shape adaptability. This work presents a simple model to determine the flexural rigidity of a beam-like, multistable metastructure used as a spar in a hybrid spanwise morphing wing. The model considers the more complex metabeam as a homogeneous beam described by Euler-Bernoulli beam theory with an equivalent flexural rigidity. The analytical model's validity is established by comparing the obtained static and dynamic responses to finite element simulations. A closed-form expression of the flexural rigidity is then given, drawing from the multistable honeycomb's material properties and the metabeam’s geometry. The model's limitations are addressed by examining several specific cases of the metabeam’s morphed configurations and a more complex metabeam structure.
{"title":"Homogenization Model for Multistable Honeycomb Metastructures with Beam-like Behavior","authors":"D. M. Boston, Andres F. Arrieta","doi":"10.33599/sj.v60no3.03","DOIUrl":"https://doi.org/10.33599/sj.v60no3.03","url":null,"abstract":"Reduced order models facilitate initial design space investigations and enable assessing the benefits of compliant structures utilized for shape adaptability. This work presents a simple model to determine the flexural rigidity of a beam-like, multistable metastructure used as a spar in a hybrid spanwise morphing wing. The model considers the more complex metabeam as a homogeneous beam described by Euler-Bernoulli beam theory with an equivalent flexural rigidity. The analytical model's validity is established by comparing the obtained static and dynamic responses to finite element simulations. A closed-form expression of the flexural rigidity is then given, drawing from the multistable honeycomb's material properties and the metabeam’s geometry. The model's limitations are addressed by examining several specific cases of the metabeam’s morphed configurations and a more complex metabeam structure.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141056597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoffrey J. Frank, Jeffrey P. Massman, Philip R. Barnett, Dennis P. Butcher
To increase the efficiency of aircraft radome structures, the potential to integrate structural, cooling, and electromagnetic (EM) transmission functions into a composite radome is being investigated. The radome configuration includes micro-channels, used for flow of cooling fluids, and embedded copper layers, used to alter the EM transmission characteristics, incorporated into a composite panel. Concepts have been developed using low dielectric loss composite for manufacturing the multilayer structure required to incorporate these multifunctional characteristics. Structural analyses and conjugate heat transfer analyses have been performed to assess the effects of channel size and position on load-carrying capability and cooling capability. Results from the analyses have been used to identify candidate configurations that will be fabricated. Fabrication concepts and results of the structural and thermal analyses are presented.
{"title":"Thermal and Structural Analysis of A Vascular Cooled Composite Radome","authors":"Geoffrey J. Frank, Jeffrey P. Massman, Philip R. Barnett, Dennis P. Butcher","doi":"10.33599/sj.v60no3.02","DOIUrl":"https://doi.org/10.33599/sj.v60no3.02","url":null,"abstract":"To increase the efficiency of aircraft radome structures, the potential to integrate structural, cooling, and electromagnetic (EM) transmission functions into a composite radome is being investigated. The radome configuration includes micro-channels, used for flow of cooling fluids, and embedded copper layers, used to alter the EM transmission characteristics, incorporated into a composite panel. Concepts have been developed using low dielectric loss composite for manufacturing the multilayer structure required to incorporate these multifunctional characteristics. Structural analyses and conjugate heat transfer analyses have been performed to assess the effects of channel size and position on load-carrying capability and cooling capability. Results from the analyses have been used to identify candidate configurations that will be fabricated. Fabrication concepts and results of the structural and thermal analyses are presented.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141034020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Magnetic polymer-based composites combine the cost-effectiveness, low density, and manufacturing flexibility of conventional polymers with the unique characteristics of magnetic powders/fillers to form multi-functional magneto polymeric composites that offer superior properties to conventional materials. At higher temperatures, magnetic properties change significantly and the particles within the magnetic powders experience sporadic motion due to the heat which causes misalignment of the magnetic domains, leading to a decrease in magnetism. Due to these adverse temperature effects, high-performance polymers such as polyetheretherketone (PEEK), polyetherimide (PEI), high-performance polyamides (HPPA), or other high-temperature thermoplastics have been considered suitable matrix for the magnetic fillers, thereby creating a much wider usage for magneto polymeric composite in applications that requires higher temperature (typically above 175°C). Thus, this review discusses the fabrication processes-injection molding, fused filament fabrication; magnetic performance, and applications of high-performance thermoplastic-based magnetic composites that can be viable for stringent engineering devices such as sensors, actuators, motors, and generators.
{"title":"High-performance Thermoplastic-based Magnetic Composites","authors":"O. Arigbabowo, Jitendra S. Tate, W. Geerts","doi":"10.33599/sj.v60no3.01","DOIUrl":"https://doi.org/10.33599/sj.v60no3.01","url":null,"abstract":"Magnetic polymer-based composites combine the cost-effectiveness, low density, and manufacturing flexibility of conventional polymers with the unique characteristics of magnetic powders/fillers to form multi-functional magneto polymeric composites that offer superior properties to conventional materials. At higher temperatures, magnetic properties change significantly and the particles within the magnetic powders experience sporadic motion due to the heat which causes misalignment of the magnetic domains, leading to a decrease in magnetism. Due to these adverse temperature effects, high-performance polymers such as polyetheretherketone (PEEK), polyetherimide (PEI), high-performance polyamides (HPPA), or other high-temperature thermoplastics have been considered suitable matrix for the magnetic fillers, thereby creating a much wider usage for magneto polymeric composite in applications that requires higher temperature (typically above 175°C). Thus, this review discusses the fabrication processes-injection molding, fused filament fabrication; magnetic performance, and applications of high-performance thermoplastic-based magnetic composites that can be viable for stringent engineering devices such as sensors, actuators, motors, and generators.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141025178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Tomblin, Rachael Andrulonis, Royal S. Lovingfoss, Brandon L. Saathoff, Cindy Ashforth, Curtis Davies
Thermoplastic composites show potential in increasing the manufacturing production rate of composite aerospace structures. This is largely due to their ability to be consolidated quickly using automated processes. A variety of reinforced thermoplastic material forms are offered that can be processed multiple ways in order to meet structural performance requirements at the necessary production volumes without substantial compromise. Intrinsically, this requires generating a significant amount of statistically-based material property data for each unique material and process combination. Currently, the National Institute for Aviation Research (NIAR) and the Federal Aviation Administration (FAA) are developing a material qualification framework for compression molded discontinuous fiber thermoplastic composites in consensus with industry experts. To aid in the development of the qualification framework, a screening test matrix was formed to identify the key processing parameters and evaluate the appropriate test methods and specimen sizes. Three main variables were considered in the trial testing: reinforcement size, material flow behavior and panel thickness. The effect of these key processing parameters on the mechanical properties are discussed along with guidelines for testing and characterization.
{"title":"Characterization Approach for Compression Molded Discontinuous Fiber Thermoplastic Composites","authors":"J. Tomblin, Rachael Andrulonis, Royal S. Lovingfoss, Brandon L. Saathoff, Cindy Ashforth, Curtis Davies","doi":"10.33599/sj.v60no1.02","DOIUrl":"https://doi.org/10.33599/sj.v60no1.02","url":null,"abstract":"Thermoplastic composites show potential in increasing the manufacturing production rate of composite aerospace structures. This is largely due to their ability to be consolidated quickly using automated processes. A variety of reinforced thermoplastic material forms are offered that can be processed multiple ways in order to meet structural performance requirements at the necessary production volumes without substantial compromise. Intrinsically, this requires generating a significant amount of statistically-based material property data for each unique material and process combination. Currently, the National Institute for Aviation Research (NIAR) and the Federal Aviation Administration (FAA) are developing a material qualification framework for compression molded discontinuous fiber thermoplastic composites in consensus with industry experts. To aid in the development of the qualification framework, a screening test matrix was formed to identify the key processing parameters and evaluate the appropriate test methods and specimen sizes. Three main variables were considered in the trial testing: reinforcement size, material flow behavior and panel thickness. The effect of these key processing parameters on the mechanical properties are discussed along with guidelines for testing and characterization.","PeriodicalId":49577,"journal":{"name":"SAMPE Journal","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140520684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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