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Understanding how protrusions, such as fins attached to flat or streamlined bodies, affect aerodynamics, especially in high-speed contexts, is vital for aerospace applications. These protrusions significantly influence overall aerodynamics and require a comprehensive understanding for accurate analysis and prediction of aerodynamic performance. This understanding is particularly critical in supersonic flight, where even minor aerodynamic disturbances can impact vehicle stability and efficiency. Therefore, a thorough understanding of protrusion-induced flow phenomena is essential for advancing aerospace engineering and improving supersonic vehicle performance and safety. The present paper focuses on the complex supersonic flow over a vertical fin, using a combination of experimental and computational methods. The study aims to understand how variations in fin height influence the behavior of the Lambda shock and any resulting changes in shock length. Specifically, the paper investigates different fin height-to-diameter (H/D) ratios ranging from 0.5 to 1.5 in steps of 0.25. To achieve this, both experimental testing in a supersonic wind tunnel and numerical simulations using the commercial CFD tool ANSYSFLUENT are employed. Through this dual approach, the paper seeks insights into the characteristics of the Lambda shock and its effects on key aerodynamic parameters, such as shock strength and drag coefficient. By thoroughly investigating these aspects, the paper contributes to a deeper understanding of the complex flow phenomena associated with supersonic flow over vertical fins, potentially guiding the design and optimization of aerospace vehicles. The outcomes indicate that a fin height of 12 mm (H/D=1.0) provides the best balance in terms of pressure distribution, Lambda shock length, and drag coefficient, making it the optimal choice for enhancing aerodynamic stability and performance in supersonic conditions. [ABSTRACT FROM AUTHOR]

Highlights The increasing reliance of the aerospace industry on lightweight yet robust materials, notably carbon fiber‐reinforced polymers (CFRPs), has emphasized the need for efficient joining methods for composite structures. This study investigates the influence of various bonding techniques on the strength of two distinct joint configurations: CFRP/CFRP and CFRP/301 steel interfaces. The CFRP/CFRP joints were configured as single lap joints, where two CFRP laminates and/or prepregs were overlapped and bonded using co‐curing, secondary bonding, or co‐bonding. The configuration ensured adhesion between the cured or uncured CFRP layers, depending on the bonding technique applied. For CFRP/301 steel, CFRP laminates and/or prepregs were similarly bonded to 301 steel substrates in an overlapping region. Both configurations were subjected to single lap shear tests following ASTM D3165 standards to assess the mechanical performance of each bonding method. The post‐test interface damage and fracture mechanisms were analyzed using optical microscopy, providing insights into the failure modes for each joint type. This study offers comprehensive experimental data on various joining techniques that can be useful during the initial design phase of aerospace systems, ultimately resulting in cost savings. The findings of this study, when analyzed from an industrial standpoint, indicate that co‐curing offers a promising solution due to its affordability and simplicity, making it especially advantageous for CFRP/301 steel overlap joining when combined with adhesive films. Co‐curing, co‐bonding, and secondary bonding techniques were applied to CFRP/steel joints in real aircraft components. The CFRP/CFRP joints obtained via co‐curing exhibited improved thermal stability and strength. Peel ply surface preparation enhanced adhesion the strength of the CFRP/CFRP bonded samples. Cohesion failure was observed in adhesive joints, with no failure at the bond lines. [ABSTRACT FROM AUTHOR]

CSAM deposition of Ti6Al4V is a challenging task, and high-quality deposits conforming to the AM application standards have not been developed so far. In our study, two distinct feedstock Ti6Al4V powders with different morphology and microstructure were used, and their influence on the key CSAM deposition parameters was investigated. The deposits were analyzed in terms of microstructure (including porosity), electrical conductivity, as well as tensile properties before and after heat treatment. The process gas temperature was found as the most influencing parameter, and the spherical plasma atomized powder resulted in a higher deposit density and electrical conductivity than the crystalline powder at 1100 °C and 50 bars. Using the optimal deposition parameters and heat treatment, unprecedented tensile properties for CSAM Ti6Al6V deposits were achieved, exhibiting 887 MPa yield strength and 929 MPa ultimate tensile strength, values that satisfy the ASTM B381 requirements for Ti6Al4V forgings, and a substantial 4.74% elongation. [ABSTRACT FROM AUTHOR]

Understanding how protrusions, such as fins attached to flat or streamlined bodies, affect aerodynamics, especially in high-speed contexts, is vital for aerospace applications. These protrusions significantly influence overall aerodynamics and require a comprehensive understanding for accurate analysis and prediction of aerodynamic performance. This understanding is particularly critical in supersonic flight, where even minor aerodynamic disturbances can impact vehicle stability and efficiency. Therefore, a thorough understanding of protrusion-induced flow phenomena is essential for advancing aerospace engineering and improving supersonic vehicle performance and safety. The present paper focuses on the complex supersonic flow over a vertical fin, using a combination of experimental and computational methods. The study aims to understand how variations in fin height influence the behavior of the Lambda shock and any resulting changes in shock length. Specifically, the paper investigates different fin height-to-diameter (H/D) ratios ranging from 0.5 to 1.5 in steps of 0.25. To achieve this, both experimental testing in a supersonic wind tunnel and numerical simulations using the commercial CFD tool ANSYS-FLUENT are employed. Through this dual approach, the paper seeks insights into the characteristics of the Lambda shock and its effects on key aerodynamic parameters, such as shock strength and drag coefficient. By thoroughly investigating these aspects, the paper contributes to a deeper understanding of the complex flow phenomena associated with supersonic flow over vertical fins, potentially guiding the design and optimization of aerospace vehicles. The outcomes indicate that a fin height of 12 mm (H/D=1.0) provides the best balance in terms of pressure distribution, Lambda shock length, and drag coefficient, making it the optimal choice for enhancing aerodynamic stability and performance in supersonic conditions.

This study presents a novel hybrid‐sandwich composite structure, customized for nose radomes applications, incorporating a foam core and distinct opposite face sheets composed of Kevlar and S‐Glass materials. Addressing in‐phase electromagnetic properties, UV protection and low velocity impact responses in our previously published work, this paper empirically and numerically investigates the damage tolerance response of the proposed structures through compression after impact (CAI) testing. The low velocity impacts (LVIs) on S‐Glass face sheets exhibited unique energy dispersion and absorption mechanisms, resulting in variations in indent damage depths and widths across all impact energy levels as compared with LVIs on Kevlar face sheets. After experimentally assessing the CAI behavior, a FE model is developed to predict CAI behavior, which closely aligned with experimental findings. This study, unprecedented in existing literature, proposes hybrid sandwich structures for nose radome aerospace applications, with superior specific impact and residual strength compared to various composite sandwich structures documented in the published literature expanding its utility beyond radomes. Highlights: Innovative composites with superior low velocity impact response, tested for compression after impact performance.Designed for nose radomes found suitable for other impact prone applications.Experimental and numerical modeling showed comparable results.Major differences observed in damage mechanics, resistance, and tolerances. [ABSTRACT FROM AUTHOR]

Real service requirements of the assembly performance and joining properties of design components are critical for composite usage in the aerospace industry. This experimental study offers a novel and comprehensive analysis of dry drilling optimization for glass-reinforced, high-performance epoxy matrix composites used in aerospace structures, focusing on thrust force and delamination. The study presents a first-time investigation into the combined effects of spindle speed (1000, 2250, 4000 and 5750 rpm), feed rate (0.2, 0.4, 0.6 and 0.8 mm/rev) and tool diameter (3 and 5 mm) using a custom-designed drill tool specifically developed for this application, filling a gap in the current literature. By employing the Taguchi design of experiments, the study identified that medium spindle speeds (2250–4000 rpm), lower feed rates (0.2 mm/rev) and smaller tool diameters (3 mm) provided optimal conditions for minimizing thrust force and delamination. These results present actionable insights into improving the structural integrity and performance of drilled aerospace-grade composite components, offering innovative advancements in both the aerospace and defense industries. [ABSTRACT FROM AUTHOR]

Hybrid nanocomposites have emerged as a groundbreaking class of materials in the aerospace industry, offering exceptional mechanical, thermal, and functional properties. These materials, composed of a combination of metallic matrices (based on aluminum, magnesium, or titanium) reinforced with a mixture of nanoscale particles, such as carbon nanotubes (CNTs), graphene, and ceramic nanoparticles (SiC, Al2O3), provide a unique balance of high strength, low weight, and enhanced durability. Recent advances in developing these nanocomposites have focused on optimizing the dispersion and integration of nanoparticles within the matrix to achieve superior material performance. Innovative fabrication techniques have ensured uniform distribution and strong bonding between the matrix and the reinforcements, including advanced powder metallurgy, stir casting, in situ chemical vapor deposition (CVD), and additive manufacturing. These methods have enabled the production of hybrid nanocomposites with improved mechanical properties, such as increased tensile strength, fracture toughness, wear resistance, and enhanced thermal stability and electrical conductivity. Despite these advancements, challenges remain in preventing nanoparticle agglomeration due to the high surface energy and van der Walls forces and ensuring consistent quality and repeatability in large-scale production. Addressing these issues is critical for fully leveraging the potential of hybrid nanocomposites in aerospace applications, where materials are subjected to extreme conditions and rigorous performance standards. Ongoing research is focused on developing novel processing techniques and understanding the underlying mechanisms that govern the behavior of these materials under various operational conditions. This review highlights the recent progress in the design, fabrication, and application of hybrid nanocomposites for aerospace applications. It underscores their potential to revolutionize the industry by providing materials that meet the demanding requirements for lightweight, high-strength, and multifunctional components. [ABSTRACT FROM AUTHOR]

In the present research article, the acoustic shock wave-resistant efficiency of silica microparticles (SiO 2 -α-cristobalite)) has been experimentally evaluated in terms of structural, optical and morphological stability against the impact of shock waves. The required SiO 2 particles were synthesized by a hydrothermal method which was subjected to a different number of shock pulses such as 200,400 and 600 with Mach number 2.2. Shocked samples' structural, morphological and optical stabilities have been evaluated by utilizing a powder X-ray diffractometer (PXRD), Ultraviolet–Diffuse reflectance spectrometer (DRS) while the surface morphological analysis has been scrutinized by the field emission scanning electron microscopic technique (FESEM) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques are utilized to evaluate oxidation states and crystallographic structural stability. The above-mentioned analytical techniques provide convincing proofs whereby the synthesized SiO 2 particles are authentically proven to possess outstanding structural, optical and morphological stability against the impact of shock waves. The implicated experimental results and the arguments strongly suggest that the SiO 2 particles are suitable candidates for aerospace and defense industry applications due to their outstanding shock wave-resistant properties. [ABSTRACT FROM AUTHOR]

Usage of thermoplastic composites with low densities is increasing, with lightness coming to the fore especially in the aerospace industry while various sectors like automotive, electronics, sport etc. are also following the trend. Important factors for the preference of thermoplastics are the increase in the amount of waste of conventional materials in addition with increasing product requirements. Composite wastes are accumulated in certain composite collection centers in the world and disposed by incineration. Until at least 2025, studies on recycling are carried out in the European Union. Within this regard, the most important feature of thermoplastics is that they can be melted and shaped again at high temperatures. In this way, recycling of fibers and matrices is possible. Mainly thermal and chemical methods are preferred for obtaining fibers while mechanical methods are preferred for obtaining the matrix. Hence, it is aimed to use both open and closed loop recycling in order to reduce wastes, energy consumption, fossil fuel consumption, and the carbon footprint. Note that these recycling approaches are also of significance for the circular economy concept. Correspondingly, this review thematizes current recycling methods for thermoplastic composites. [ABSTRACT FROM AUTHOR]

Carbon-carbon composites are advanced materials known for their high strength, high-temperature stability, and superior thermal conductivity. Mechanical properties such as tensile strength, flexural strength, and compressive strength are examined, as well as thermal properties like the coefficient of thermal expansion and thermal conductivity, to understand the characteristics of the composite. Carbon-carbon composites are ideal for the aerospace industry's need for lightweight and high-performance materials. Tribological and surface properties are relevant to this discussion, given the use case of carbon-carbon composites in extreme conditions, the effect of exposing the composite to different fluids and the change in friction and wear properties. Coatings can protect the composite from environmental factors such as UV radiation, oxidation, and erosion. Self-healing composites that can repair themselves can increase the lifespan of structures while reducing maintenance costs. These have been used in aerospace applications such as airplane braking systems, rocket nozzles, and re-entry vehicle heat shields. Furthermore, researchers have recently addressed the problem of finishing and drilling without delamination and loss of properties, and this study looks into unconventional methods that can be adopted for the same. This study aims to provide an overview of the current state of carbon-carbon composite materials and their applications. [ABSTRACT FROM AUTHOR]

In this paper, the improvement of mechanical and thermal characteristics in nanocomposites with addition of CNTs is studied. As a result of CNTs structure and characteristics, the tensile strength, elasticity, toughness as well as thermal conductivity of CNT-reinforced nanocomposites are enhanced. This section presents key issues related to the CNTs such as dispersion, agglomeration, and cost together with the state-of-art of manufacturing procedure. Real-world applications for aerospace and electronics sectors plus energy storage are described and prospects for future research are outlined. Based on this study, nanocomposites of CNT are believed to have unprecedented opportunities for delivering value add for advanced material needs in today's high-stakes industries. [ABSTRACT FROM AUTHOR]

This study focuses on understanding of thermal and mechanical characteristics of Hybrid Composites & their utilization in high-performance Sectors like Aerospace, Automobiles, Shipbuilding & Renewable Systems. The report analyses how different materials such as carbon, glass, and natural fibers improve the strength, flexibility, thermal stability, and heat resistance of composites. These properties including thermal conductivity, thermal expansion, tensile strength, compressive strength, and fatigue resistance are analyzed with the help of examples taken from industries. The following findings suggest that hybrid composites outcompete fundamental materials in aspects such as mechanical strength and thermal control, thereby qualifying hybrid composites for sensitive applications. It also notes that work is currently being conducted on incorporating nanotechnology and bio-based composites in order to enhance performance and reduce the sector's impact on the environment. The conclusions point to the fact that hybrid composites find more and more applications in modern engineering and present research prospects to examine the manufacturing problems and environmental effects of hybrid composites. [ABSTRACT FROM AUTHOR]

A series of experimental and numerical studies were carried out on the mechanical and geometric performance of an aerostructural part produced by a material out-of-autoclave stamp forming process using unidirectional (UD) carbon fiber (CF) reinforced polyetherketoneketone (PEKK), which provides advantages like reshaping, recycling, welding, and low serial manufacturing costs. As a novelty, initial part geometry, different types of springs, and their attachment type were examined experimentally and compared with simulations. Compression tests were performed to determine mechanical strengths which reach levels up to 550 MPa. In addition, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to determine the crystallinity which occurs depending on the cooling regimes of the material. The crystallinity has been observed to vary regionally ranging from 16 to 21%. However, the crystallinity of the part towards the cold mold region decreased from 20 to 17%. In addition, simulations were performed to observe and control the occurrence of wrinkles and other defects. [ABSTRACT FROM AUTHOR]

Numerical techniques are developed to generate innovative lightweight designs, difficult to obtain with traditional product manufacturing technologies. The use of advanced engineering design software makes it possible to generate un‐conventional geometries, combining a standard density‐based topology optimization approach with lattice structure‐based methods. Deep knowledge of modeling aspects is required to improve the topology optimization processes currently performed in aerospace applications, as well as to achieve design solutions suitably prepared for additive manufacturing technologies. In the present work, algorithms based on solid isotropic material with penalization (SIMP) method are used to reduce the weight of parts by removing unnecessary material from the initial part design. Moreover, the integration of lattice structures in the topology optimization procedures allows for a further part weight reduction offering the possibility of exploiting the potentials of 3D printing in the fabrication of complex geometries. [ABSTRACT FROM AUTHOR]

The present paper investigates the application of laser beam shaping and laser beam oscillations (wobbling) for laser processing of the crack-prone aluminum alloy 6013, used in automotive and aerospace applications. A comparison of different laser beam profiles, such as the commonly used Gaussian profile, a ring-core distribution with the intensity of 50 % in the ring and 50 % in the core, and a ring-shaped beam profile shows different cracking behavior of the material. The ring-shaped beam profile shows the most promising results due to a reduction of the thermal gradient G and an enhancement of the growth rate R, which isalso stated by the state of the art. A combination of laser beam shaping and laser beam oscillations shows reproducible crack-free processing of Al6013 sheets at all three beam profiles at different parameter combinations. The crack elimination can be attributed to the emergence of a more pronounced equiaxed grain structure in the fusion zone of the weld with the application of laser beam oscillations and laser beam shaping. Thus, the temperature gradient G, the growth rate R and, therefore, the cooling rate can be controlled with the presented variation of the laser beam shapes and scanning strategies. Furthermore, the penetration depth of the laser at a Gaussian beam profile can be reduced using laser beam shaping, showing shallower melt pools with a lower depth-to-width aspect ratio, also suitable for the process of powder bed fusion of metals using a laser-based system (PBF-LB/M).

The aerospace industry has progressively grown its use of composites. Electrically conductive nanocomposites are among important modern materials for this sector. We report on a bulk composite containing silver nanowires (AgNW) and an aerospace grade epoxy for use in carbon fiber reinforced polymers (CFRPs). AgNWs' surfaces were also modified to enhance their ability to be dispersed in epoxy. Composites were obtained by use of three-roll milling which is of major interest for industrial applications, especially for the aerospace sector, since the process is scalable and works for aerospace grade resins with high curing temperatures. Our main objective is to improve the electromagnetic interference (EMI) shielding performance of CFRPs via improving the properties of the resin material. The addition of AgNWs did not considerably alter the flexural strength of the epoxy, however the composite with surface-modified AgNWs has a 46 % higher flexural strength. Adding AgNWs over a low threshold concentration of 0.05 wt% significantly enhanced the electrical conductivity. Conductivities above the percolation threshold lie around 102 S/m. At a concentration of 5 wt% AgNW, the EMI shielding efficiency (SE) of epoxy increased from 3.49 to 12.31 dB. Moreover, the thermal stability of the epoxy was unaffected by AgNWs. As a result, it was discovered that (surface modified) AgNWs improved the (multifunctional) capabilities of the aerospace grade epoxy resin which might be used in CFRPs to further enhance properties of composites parts, demonstrating suitability of AgNWs' as a reinforcement material in aerospace applications. [ABSTRACT FROM AUTHOR]

The thermal conductivity coefficient of epoxy composites for aircraft, which are reinforced with glass fiber and filled with aerosil, γ-aminopropylaerosil, aluminum oxide, chromium oxide, respectively, was simulated. To this end, various machine learning methods were used, in particular, neural networks and boosted trees. The results obtained were found to be in good agreement with the experimental data. In particular, the correlation coefficient in the test sample was 0.99%. The prediction error of neural networks in the test samples was 0.5; 0.3; 0.2%, while that of boosted trees was 1.5; 0.9%. [ABSTRACT FROM AUTHOR]

The issue of thermal control for space missions has been critical since the early space missions in the late 1950s. The demands in such environments are heightened, characterized by significant temperature variations and the need to manage substantial densities of heat. The current work offers a comprehensive survey of the innovative materials and thermal fluids employed in the aerospace technological area. In this scope, the materials should exhibit enhanced reliability for facing maintenance and raw materials scarcity. The improved thermophysical properties of the nanofluids increase the efficiency of the systems, allowing the mass/volume reduction in satellites, rovers, and spacecraft. Herein are summarized the main findings from a literature review of more than one hundred works on aerospace thermal management. In this sense, relevant issues in aerospace convection cooling were reported and discussed, using heat pipes and heat exchangers, and with heat transfer ability at high velocity, low pressure, and microgravity. Among the main findings, it could be highlighted the fact that these novel materials and fluids provide enhanced thermal conductivity, stability, and insulation, enhancing the heat transfer capability and preventing the malfunctioning, overheating, and degradation over time of the systems. The resulting indicators will contribute to strategic mapping knowledge and further competence. Also, this work will identify the main scientific and technological gaps and possible challenges for integrating the materials and fluids into existing systems and for maturation and large-scale feasibility for aerospace valorization and technology transfer enhancement. [ABSTRACT FROM AUTHOR]

Carbon-carbon composites are advanced materials known for their high strength, high-temperature stability, and superior thermal conductivity. Mechanical properties such as tensile strength, flexural strength, and compressive strength are examined, as well as thermal properties like the coefficient of thermal expansion and thermal conductivity, to understand the characteristics of the composite. Carbon-carbon composites are ideal for the aerospace industry’s need for lightweight and high-performance materials. Tribological and surface properties are relevant to this discussion, given the use case of carbon-carbon composites in extreme conditions, the effect of exposing the composite to different fluids and the change in friction and wear properties. Coatings can protect the composite from environmental factors such as UV radiation, oxidation, and erosion. Self-healing composites that can repair themselves can increase the lifespan of structures while reducing maintenance costs. These have been used in aerospace applications such as airplane braking systems, rocket nozzles, and re-entry vehicle heat shields. Furthermore, researchers have recently addressed the problem of finishing and drilling without delamination and loss of properties, and this study looks into unconventional methods that can be adopted for the same. This study aims to provide an overview of the current state of carbon-carbon composite materials and their applications.

High melting point materials are essential to many different industries because of their unique qualities, rendering them invaluable for various uses. This paper investigates the unique features of high melting point materials, summarizes current advancements in the field, and outlines the vast range of applications that these materials have in domains like materials science, aerospace, energy, and electronics. The discourse covers various materials, such as carbon-based, ceramics, intermetallic, and refractory metals, emphasizing their potential uses and new roles in contemporary technology. Thanks to developments in material science, new high melting point materials with enhanced mechanical strength, thermal stability, and resistance to harsh environments have been found and synthesized. These materials are used in manufacturing, electronics, aircraft, and energy. They are frequently distinguished by their resistance to temperatures significantly higher than those of ordinary materials. High melting point materials are used in the aerospace sector to manufacture heat-resistant parts that improve spacecraft and jet engines' overall performance and longevity. These materials are also essential to the energy sector's creation of sophisticated thermal management systems for nuclear reactors and high-temperature environments, improving energy generation efficiency and security. The electronic industry benefits from high melting point materials when producing semiconductors and other electronic components since their stability guarantees dependable operation even in harsh circumstances.Furthermore, high melting point materials are becoming increasingly popular in additive manufacturing procedures, allowing complex structures with exceptional heat resistance to be produced for various uses. Moreover, high melting point alloys and composites have been developed due to advances in metallurgy and nanotechnology, broadening their potential uses in industries including automobile engineering, medical technology, and military technology. The interdisciplinary aspect of high melting point material research and development is shown in this abstract, which also highlights the adaptability of materials and their revolutionary effects on various industries. The continuous investigation of these materials shows promise for future discoveries that will open up new avenues and applications in fields vital to the development of contemporary society.

Hybrid nanocomposites have emerged as a groundbreaking class of materials in the aerospace industry, offering exceptional mechanical, thermal, and functional properties. These materials, composed of a combination of metallic matrices (based on aluminum, magnesium, or titanium) reinforced with a mixture of nanoscale particles, such as carbon nanotubes (CNTs), graphene, and ceramic nanoparticles (SiC, Al2O3), provide a unique balance of high strength, low weight, and enhanced durability. Recent advances in developing these nanocomposites have focused on optimizing the dispersion and integration of nanoparticles within the matrix to achieve superior material performance. Innovative fabrication techniques have ensured uniform distribution and strong bonding between the matrix and the reinforcements, including advanced powder metallurgy, stir casting, in situ chemical vapor deposition (CVD), and additive manufacturing. These methods have enabled the production of hybrid nanocomposites with improved mechanical properties, such as increased tensile strength, fracture toughness, wear resistance, and enhanced thermal stability and electrical conductivity. Despite these advancements, challenges remain in preventing nanoparticle agglomeration due to the high surface energy and van der Walls forces and ensuring consistent quality and repeatability in large-scale production. Addressing these issues is critical for fully leveraging the potential of hybrid nanocomposites in aerospace applications, where materials are subjected to extreme conditions and rigorous performance standards. Ongoing research is focused on developing novel processing techniques and understanding the underlying mechanisms that govern the behavior of these materials under various operational conditions. This review highlights the recent progress in the design, fabrication, and application of hybrid nanocomposites for aerospace applications. It underscores their potential to revolutionize the industry by providing materials that meet the demanding requirements for lightweight, high-strength, and multifunctional components.

CSAM (cold spray additive manufacturing) of Ti6Al4V is a challenging task and high-quality deposits conforming to the AM application standards have not been developed so far. In our study, two distinct feedstock Ti6Al4V powders with different morphology and microstructure, spherical and crystalline, were used and their influence on the deposits was investigated in terms of microstructure as well as tensile properties. The results indicate the mechanical strength and ductility of the as-deposited samples to be in the range of 8–30 % compared to wrought Ti6Al4V and highlight a significant anisotropy in different in-plane directions. The post-treatments of the deposits from the spherical, plasma atomized powder effectively reduced the porosity and triggered microstructural homogenization and recrystallization, leading to a significant increase in the yield and tensile strengths, reaching 892 MPa and 954 MPa, respectively, while achieving an enormous enhancement in the elongation to 21.6 % at the same time. This was in a striking contrast to the deposits from the crystalline powder: despite the yield and tensile strength increase to 853 MPa and 1058 MPa, respectively, the elongation remained virtually zero, highlighting the importance of the feedstock powder selection in cold spray additive manufacturing of Ti6Al4V.

Delamination due to an inferior adhesion between reinforcement material and matrix in carbon fiber-reinforced thermoplastic (CFRTP) composites is a crucial problem to be solved. To this end, this study aims to overcome poor wettability between reinforcing phase, i.e., carbon fiber (CF), and thermoplastic matrix, i.e., polyetherether ketone (PEEK). Herein, CF's surface was tailored by application of different polymeric sizing agents which have different chemical structures. Morphology and topology analyses were performed by Scanning Electron Microscope and 3D laser scanning, respectively. Later, a variety of wettability results were obtained by the sessile drop method used in Contact Angle (CA) measurements for CFs throughout application of each sizing agent applied by dip coating. Sizing materials were designed such that the chemical structure of CF's surface could exhibit compatibility with the matrix itself. Consequently, complete wettability (CA: 0°) was achieved for CFs sized by HPEEK (CF/hydroxylated PEEK (HPEEK)) and the surface free energy (SFE) of CF was enhanced from 5.43 to 72.8 mJ/m2 while the SFE of the PEEK matrix is 40.1 mJ/m2. Moreover, sizing by HPEEK improved the average surface roughness of CF by 32% which enables optimized adhesion. Afterward, repetitive tensile tests were carried out to observe effects of improved interfacial interlocking on the mechanical properties of the final CFRTP composite. Stress–strain curves revealed that the tensile strength of CFRTP improved from 473 to 508 MPa through the sizing of CF by HPEEK whereas pristine PEEK has a much smaller tensile strength (98 MPa) than the aforementioned CF-reinforced composites. The sizing of carbon fiber's surface by HPEEK resulted in an enhanced adhesion with the PEEK matrix. Since the chemical structure and physical properties of sizing agent and matrix are compatible, potential debonding between them was eliminated. Thus, the improved wettability led to a substantial increase in the mechanical strength of the final TP composite. [ABSTRACT FROM AUTHOR]

Varying graphene nanoplatelet (GNP) and hexagonal boron nitride (h‐BN) based fillers were integrated to an aerospace grade epoxy resin typically used as matrix to obtain or repair structural parts of aerospace platforms. The three‐roll milling approach was used for this purpose. Five cycles were performed for the mixing while the gap between rollers was 50 μm. Microstructure and thermal properties of the nanocomposites were studied. Moreover, mechanical and transport (electrical as well as thermal) performances were investigated. Results show that certain fillers yield multifunctional properties, that is, enhanced flexural strength by up to 69% in combination with high electrical conductivities with orders of magnitude of approximately 103Sm and improved thermal conductivities up to 9.3%. For instance, the hybrid nanocomposite sample produced with 0.5 wt% GNP and 0.5 wt% h‐BN added to the epoxy matrix exhibits an electrical conductivity which increased 108 fold, a flexural strength increased by 69% and thermal conductivity increased by 7% in comparison the neat epoxy. Hence, in this study it was demonstrated that these properties can be engineered and tuned effectively for aerospace applications like lightweight avionic chassis which have specific requirements like thermal and electric conductivity which naturally leads to the possible usage of GNP and h‐BN in an epoxy. Correspondingly, presented results are of relevance for novel thermal interface materials with tailored electrical properties. [ABSTRACT FROM AUTHOR]

Glare (Glass Reinforced Aluminium) which consists of fibre metal laminate composite consisting of aluminium and glass is used aerospace structures are supposed to buckling and impact loads. Lateral buckling analyses were made to determine critical buckling loads, and results were compared to Al 2024-T3 in this paper. Weight and load carrying capacity of Glare grades were taken into consideration and the importance of weight to critical load was stated. Numerical works were carried out by starting with Glass and Aluminum then continued for Glare Grades of Glare 2A, Glare 2B, Glare 3A, Glare 3B, Glare 4A, Glare 4B, Glare 5A, Glare 5B, Glare 6A and Glare 6B to estimate buckling load values. Several comparisons were presented for Glare grades based on Al 2024-T3 through paper. Glare 2A, 2B, 3A, 3B, 6A and 6B Grades have lower weight and buckling load values compared to Al 2024-T3. Lower weight is essential for aerospace applications. But optimum weight and load carrying capacity can be selected for intended applications by taking weight and load into consideration at same time. Although Glare grades of 4A 2-1, 4B 2-1, 5A 2-1 and 5B 2-1 having closer weight (17.60g, 17.60g, 19.13g and 19.13g respectively) to Al 2024-T3 (17.31g), higher buckling loads were determined for Glare grades numerically. The best choice for Glare as an alternative to Al 2024-T3 under lateral buckling loading can be decided for point of views of less weight to critical load ratio.

The editorial discusses the potential of additive manufacturing (AM) or 3D printing to revolutionize the ceramic industry by enabling the production of complex ceramic components directly from digital models. The use of AM techniques can reduce production costs, lead times, and enhance design flexibility. The research topic includes articles from various groups worldwide, highlighting recent progress in AM of advanced ceramic materials and applications in fields such as aerospace, biomedicine, and tissue engineering. The authors also emphasize the importance of artificial intelligence (AI) in advancing AM processes for quality control and innovative material solutions. [Extracted from the article]

Polyimide (PI)-silica aerogel composite aerogels with low shrinkage (3.7%), low density (0.061 g/cm3), low thermal conductivity (0.0216 W m−1 K−1), high hydrophobicity (146°) and good fire resistance were prepared by incorporating silica aerogel powders into PI matrix. The properties of the aerogels are affected by the type and content of silica aerogel powders. The samples show high compressibility, and the stress at 80% strain increases with the increase of silica aerogel powder content. The addition of inorganic silica aerogel powders (ISAp) can improve the thermal stability of the aerogel and the fire resistance and structural integrity of the sample under flame, but has adverse effect on moisture resistance. While the addition of polyvinylpolymethylsiloxane aerogel powders (PAp) improves the moisture resistance of the aerogel but weakens the thermal stability and fire resistance. The introduction of both ISAp and PAp can reduce the thermal conductivity of the aerogel, and the samples exhibit good thermal insulation performance. Furthermore, ground equivalent simulation tests were carried out to verify the adaptability of these aerogels in the space environment. The sample meets the standard requirements and shows stable structure and performance during the tests, which proves its potential application in the aerospace field.

The focus of this research is to develop a specialized multidisciplinary design optimization framework for composite sandwich-structured radomes. Radomes play a crucial role in safeguarding antenna systems from challenging environmental conditions. However, they can adversely impact the electromagnetic performance of the antenna. Unlike traditional approaches that separately address electromagnetic performance and mechanical responses, our framework considers both aspects concurrently, resulting in a more efficient process. The main objectives of the optimization are to enhance electromagnetic performance while also accounting for deformations, material integrity, and structural stability. To evaluate the electromagnetic performance, a 3-dimensional numerical simulation is employed to analyze parameters such as electromagnetic transmission loss, bore sight error, and side lobe characteristics. The model's accuracy is verified through experimental testing in an anechoic chamber, utilizing a hybrid sandwich structure. The results indicate minimal attenuation, with an average loss of only 1.5 % in the transmission of antenna signals, using the proposed radome thickness. Furthermore, the configuration of the material provides structural stability, ensuring a factor of safety of 2.5 while satisfying operational constraints. Hence, the proposed multidisciplinary optimization model represents an efficient and feasible approach to radome design. This advancement in the field equips engineers and researchers with a valuable tool to develop dependable and effective radome systems.

An experimental study was conducted to investigate the phenomenon of UAV attitude instability caused by large vibrations affecting single‐rotor UAV airborne equipment. Appropriate measurement points were selected to collect vibration signals from the unmanned aerial platform during takeoff and flight of the drone. The time‐domain response and power spectral density of the unmanned aerial platform were then obtained. Establish a dynamic model of the vibration reduction system for an unmanned aerial platform and design a two‐stage vibration reduction structure for the unmanned aerial platform. Through field flight tests of unmanned aerial vehicles, it has been demonstrated that the maximum time domain response of the platform after vibration reduction is 8.75 g (less than 50 g), and the maximum root mean square value of the power spectral density (PSD) is 1.82 g (less than 3 g). The designed secondary vibration reduction structure can serve as a reference for the design of vibration reduction in unmanned aerial vehicles. [ABSTRACT FROM AUTHOR]

Glare (Glass Reinforced Aluminium) which consists of fibre metal laminate composite consisting of aluminium and glass is used aerospace structures are supposed to buckling and impact loads. Lateral buckling analyses were made to determine critical buckling loads, and results were compared to Al 2024-T3 in this paper. Weight and load carrying capacity of Glare grades were taken into consideration and the importance of weight to critical load was stated. Numerical works were carried out by starting with Glass and Aluminum then continued for Glare Grades of Glare 2A, Glare 2B, Glare 3A, Glare 3B, Glare 4A, Glare 4B, Glare 5A, Glare 5B, Glare 6A and Glare 6B to estimate buckling load values. Several comparisons were presented for Glare grades based on Al 2024-T3 through paper. Glare 2A, 2B, 3A, 3B, 6A and 6B Grades have lower weight and buckling load values compared to Al 2024-T3. Lower weight is essential for aerospace applications. But optimum weight and load carrying capacity can be selected for intended applications by taking weight and load into consideration at same time. Although Glare grades of 4A 2-1, 4B 2-1, 5A 2-1 and 5B 2-1 having closer weight (17.60g, 17.60g, 19.13g and 19.13g respectively) to Al 2024-T3 (17.31g), higher buckling loads were determined for Glare grades numerically. The best choice for Glare as an alternative to Al 2024- T3 under lateral buckling loading can be decided for point of views of less weight to critical load ratio. [ABSTRACT FROM AUTHOR]

Abstract An experimental study was conducted to investigate the phenomenon of UAV attitude instability caused by large vibrations affecting single‐rotor UAV airborne equipment. Appropriate measurement points were selected to collect vibration signals from the unmanned aerial platform during takeoff and flight of the drone. The time‐domain response and power spectral density of the unmanned aerial platform were then obtained. Establish a dynamic model of the vibration reduction system for an unmanned aerial platform and design a two‐stage vibration reduction structure for the unmanned aerial platform. Through field flight tests of unmanned aerial vehicles, it has been demonstrated that the maximum time domain response of the platform after vibration reduction is 8.75 g (less than 50 g), and the maximum root mean square value of the power spectral density (PSD) is 1.82 g (less than 3 g). The designed secondary vibration reduction structure can serve as a reference for the design of vibration reduction in unmanned aerial vehicles.

The issue of thermal control for space missions has been critical since the early space missions in the late 1950s. The demands in such environments are heightened, characterized by significant temperature variations and the need to manage substantial densities of heat. The current work offers a comprehensive survey of the innovative materials and thermal fluids employed in the aerospace technological area. In this scope, the materials should exhibit enhanced reliability for facing maintenance and raw materials scarcity. The improved thermophysical properties of the nanofluids increase the efficiency of the systems, allowing the mass/volume reduction in satellites, rovers, and spacecraft. Herein are summarized the main findings from a literature review of more than one hundred works on aerospace thermal management. In this sense, relevant issues in aerospace convection cooling were reported and discussed, using heat pipes and heat exchangers, and with heat transfer ability at high velocity, low pressure, and microgravity. Among the main findings, it could be highlighted the fact that these novel materials and fluids provide enhanced thermal conductivity, stability, and insulation, enhancing the heat transfer capability and preventing the malfunctioning, overheating, and degradation over time of the systems. The resulting indicators will contribute to strategic mapping knowledge and further competence. Also, this work will identify the main scientific and technological gaps and possible challenges for integrating the materials and fluids into existing systems and for maturation and large-scale feasibility for aerospace valorization and technology transfer enhancement.