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RAMBHA-LP (Radio Anatomy of Moon Bound Hypersensitive Ionosphere and Atmosphere - Langmuir Probe) is one of the key scientific payloads onboard the Indian Space Research Organization’s (ISRO) Chandrayaan-3 mission. Its objectives were to estimate the plasma density and its variations on the near lunar surface. The probe was initially kept in a stowed condition attached to the lander. A mechanism was designed and realized to meet the functional requirement of deploying the probe at a distance of 1 meter, equivalent to the Debye length of the probe in the moon’s plasma environment. The probe deployment mechanism consists of the Titanium alloy spherical probe with a Titanium Nitride coating on its surface to achieve a constant work function, a long carbon-fiber-reinforced polymer boom, a double torsion spring, a dust-protection box, and a shape-memory alloy-based Frangibolt actuator for low-shock separation. The entire mechanism weighed less than 1.5 kilograms.

Abstract: The present study discusses about the effect of installation torque on the surface and subsurface deformations for thin walled 7075 aluminum alloy used in Aerospace applications. A FE model was constructed to predict the effect of torque induced stresses on thin walled geometry followed with an experimentation. A detailed surface analysis was performed on 7075 aluminum in terms of superficial discontinuities, residual stresses, and grain deformations. The localized strain hardening resulting from increased dislocation density and its effect on surface microhardness was further studied using EBSD and micro indentation. The predicted surface level plastic strain of .25% was further validated with grain deformations measured using optical and scanning electron microscopy.

Abstract: Hydraulic systems in aircrafts largely comprise of metallic components with high strength to weight ratios which comprise of 2024 Aluminum and Titanium Ti-6AL-4V. The selection of material is based on low and high pressure applications respectively. For aircraft fluid conveyance products, hydraulic conduits are fabricated by axisymmetric turning to support flow conditions. The hydraulic conduits further carries groves within for placement of elastomeric sealing components. This article presents a systematic study carried out on common loads experienced by fluid carrying conduits and the failure modes induced. The critical failure locations on fluid carrying conduits of 2024-T351 Aluminum was identified, and the Scanning Electron Microscope (SEM) analysis was carried out to identify the characteristic footprints of failure surfaces and crack initiation. Through this analysis, a load to failure mode correlation is established.

Aerospace structural components grapple with the pressing issue of high-cycle fatigue-induced micro-crack initiation, especially in high-performance alloys like Titanium and super alloys. These materials find critical use in aero-engine components, facing a challenging combination of thermo-mechanical loads and vibrations that lead to gradual dislocations and plastic strain accumulation around stress-concentrated areas. The consequential vibration or overload instances can trigger minor cracks from these plastic zones, often expanding unpredictably before detection during subsequent inspections, posing substantial risks. Effectively addressing this challenge demands the capability to anticipate the consequences of operational life and aging on these components. It necessitates assessing the likelihood of crack initiation due to observed in-flight vibration or overload events.

The present study focuses on the impacts of pistachio shell particles (2–10 wt.%) on the mechanical and microstructures properties of Al–Cu–Mg/pistachio shell particulate composites. To inspect the impact of the pistachio shell powder content with Al–Cu–Mg alloys, the experimentation was carried out with different alloy samples with constant copper (Cu) and magnesium (Mg) content. Parameters such as hardness, tensile strength with yield strength and % elongation, impact energy, and microstructure were analyzed. The outcomes demonstrated that the uniform dissemination of the pistachio shell particles with the microstructure of Al–Cu–Mg/pistachio shell composite particulates is the central point liable for the enhancement of the mechanical properties. Incorporating pistachio shell particles, up to 10 wt.%, is a cost-effective reinforcement in the production of metal matrix composites for various manufacturing applications.

Fracture characterization of automotive metals under simple shear deformation is critical for the calibration of advanced fracture models employed in forming and crash simulations. In-plane shear fracture tests of high ductility materials have proved challenging since the sample edge fails first in uniaxial tension before the fracture limit in shear is reached at the center of the gage region. Although through-thickness machining is undesirable, it appears required to promote higher strains within the shear zone. The present study seeks to adapt existing in-plane shear geometries, which have otherwise been successful for many automotive materials, to have a local shear zone with a reduced thickness. It is demonstrated that a novel shear zone with a pocket resembling a “peanut” can promote shear fracture within the shear zone while reducing the risk for edge fracture. An emphasis was placed upon machinability and surface quality for the design of the pocket in the shear zone.

A natural fiber based polymer composite has the advantage of being more environment-friendly from a life cycle standpoint when compared to composites reinforced with widely-used synthetic fibers. The former category of composites also poses reduced health risks during handling, formulation and usage. In the current study, jute polymer laminates are studied, with the polymeric resin being a general purpose polyester applied layer-by-layer on bi-directionally woven jute plies. Fabrication of flat laminates following the hand layup method combined with compression molding yields a jute polymer composite of higher initial stiffness and tensile strength, compared to commonly used plastics, coupled with consistency for engineering design applications. However, the weight-saving potential of a lightweight material such as the current jute-polyester composite can be further enhanced through improvement of its behavior under mechanical loading.

This research focuses on the commercial 6111 aluminum alloy as the subject of investigation. By designing tensile specimens with the same characteristic dimensions but varying fillet radii, the effects of fillet radius on the tensile properties and stress concentration effects of the aluminum alloy were studied through tensile testing and digital image correlation techniques. The results demonstrate that with an increase in fillet radius, the failure strength and stress distribution of the aluminum alloy specimens have both undergone alterations. This phenomenon can be attributed to the reduction of stress concentration at the fillet due to the larger fillet radius. Further verification through digital image correlation reaffirms that samples with a fillet radius of 10mm exhibit notable stress concentration effects at the fillet, while specimens with a fillet radius increased to 40mm display uniform plastic deformation across the parallel section.

Self-piercing riveting (SPR) are one of most important joining approaches in lightweight vehicle design for Body-in-white (BIW) manufacturing. Numerical simulation of the riveting process could significantly boost design efficiency by reducing trial-and-error experiments. The traditional Finite Element Method (FEM) with element erosion is hard to capture the large plastic deformation and complex failure behaviors in the SPR process. The smoothed Particle Galerkin Method (SPG) is a genuine meshless method based on Galerkin's weak form, which uses a novel bond-based failure mechanism to keep the conservation of mass and momentum during the material failure process. This study utilizes a combined FEM and SPG approach to join Aluminum sheet 5754 using a full three-dimensional (3D) model in LS-DYNA/explicit.

In the racing world, speed is everything, and the Formula Student cars are no different. As one of the key means to improve the speed of the car, lightweight plays an important role in the racing world. The weight reduction of unsprung metal parts can not only improve the driving speed, but also effectively optimize the dynamic of the car, so the lightweight design of unsprung parts has attracted much attention. In the traditional Formula Student racing car, the hub and spoke are two independent parts, they are fixed by four hub bolts or a central locking nut, the material of these fasteners is usually steel, so it brings a lot of weight burden. In order to achieve unsprung lightweight, a new type of wheel part design of Formula Student racing car is proposed in this paper. The hub and spoke are designed as integrated aluminum alloy parts, effectively eliminating the mass of hub bolts or central locking nuts.

This study delves into the microstructural and mechanical characteristics of AlSi10Mg alloy produced through the Laser Powder Bed Fusion (L-PBF) method. The investigation identified optimal process parameters for AlSi10Mg alloy based on Volume Energy Density (VED). Manufacturing conditions in the L-PBF process involve factors like laser power, scan speed, hatching distance, and layer thickness. Generally, high laser power may lead to spattering, while low laser power can result in lack-of-fusion areas. Similarly, high scan speeds may cause lack-of-fusion, and low scan speeds can induce spattering. Ensuring the quality of specimens and parts necessitates optimizing these process parameters. To address the low elongation properties in the as-built condition, heat treatment was employed. The initial microstructure of AlSi10Mg alloy in its as-built state comprises a cell structure with α-Al cell walls and eutectic Si.

Upcoming, increasingly stringent greenhouse gas (GHG) as well as emission limits demand for powertrain electrification throughout all vehicle applications. Increasing complexity of electrified powertrain architectures require an overall system approach combining modular component technology with integration and industrialization requirements when heading for further significant efficiency optimization. At the same time focus on reduced development time, product cost and minimized additional investment demand reuse of current production, machining, and assembly facilities as far as possible. Up to date additive manufacturing (AM) is an established prototype component, as well as tooling technology in the powertrain development process, accelerating procurement time and cost, as well as allowing to validate a significantly increased number of variants. The production applications of optimized, dedicated AM-based component design however are still limited.

Aluminum alloy has become an indispensable part of the automotive industry because of its excellent mechanical properties such as lightweight, high strength, high reliability, maintainability, and low cost. Aluminum alloy is used in automobiles, such as engine blocks, cylinder heads, intake manifolds, brake components, and fuel tanks. Fatigue and fracture are the main reasons for its engineering failure. Surface strengthening techniques, such as ultrasonic shot peening (USP), are often used to improve the fatigue resistance of aluminum alloys. This article expounds on the working principle of USP and elucidates the influence of USP process parameters on the surface characteristics of aluminum alloy. Experimental results observed the effects of USP parameters on surface properties such as surface roughness, microhardness, and surface morphology.

Strength, creep, and fatigue of the chassis components are greatly influenced by the material used and its manufacturing process. Alloy wheel is one of the critical chassis components manufactured using the casting process. Secondary Dendrite Arm Spacing (SDAS) is one of the important microstructural parameters generated during the solidification stage of the casting process. SDAS has a significant role in altering the mechanical properties and the behavior of the component. Variation in solidification time and alloy composition will have a major impact in SDAS. The combined effect of SDAS with microstructural variations and the strength behavior has not been studied in earlier literature for an alloy wheel. The scope of this study is to perform casting simulation for an alloy wheel, predict the SDAS and capture the variation of mechanical properties (yield strength, ultimate tensile strength & elongation).

At the dawn of battery electric vehicles (BEVs), protection of automotive battery systems as well as passengers, especially from severe side impact, has become one of the latest and most challenging topics in the BEV crashworthiness designs. Accordingly, two material-selection concepts are being justified by the automotive industry: either heavy-gauge extruded aluminum alloys or light-gauge advanced high-strength steels (AHSSs) shall be the optimal materials to fabricate the reinforcement structures to satisfy both the safety and lightweight requirements. In the meantime, such a justification also motivated an ongoing C-STARTM (Cliffs Steel Tube as Reinforcement) Protection project, in which a series of modularized steel tube assemblies, were demonstrated to be more cost-efficient, sustainable, design-flexible, and manufacturable than the equivalent extruded aluminum alloy beams as BEV reinforcement structures.

A growing number of industries are utilizing friction stir welding (FSW), which has shown promise for joining different materials. In this study, the impacts of rotation speed and tool pin shape are examined, as well as the FSW zone generation in the magnesium alloy AZ31. The physical attributes of rotation speed, feed rate, pin profile shape, and the mechanical properties of the AZ31 magnesium alloy hardness, impact energy, and tensile strength are examined in this research to determine the properties of FSW. Under optimal conditions, taper-threaded tool pins, 40 mm/min welding speed, and 1000 rpm rotation speed achieved maximal micro-hardness. The FSW tool creates heat at 1000 rpm, improving the softened metal’s mechanical properties. Thus, the metal content in the stir zone was uniform. Some process variables impacted the response surface methodology (RSM) parametric design and subsequent optimization procedure.

The aerospace industry's unceasing quest for lightweight materials with exceptional mechanical properties has led to groundbreaking advancements in material technology. Historically, aluminum alloys and their composites have held the throne in aerospace applications owing to their remarkable strength-to-weight ratio. However, recent developments have catapulted magnesium and its alloys into the spotlight. Magnesium possesses two-thirds of aluminum's density, making it a tantalizing option for applications with regard to weight-sensitive aerospace components. To further enhance magnesium's mechanical properties, researchers have delved into the realm of metal matrix composites (MMCs), using reinforcements such as Alumina, Silicon carbide, Boron carbide and Titanium carbide.

The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools.

Powder metallurgy of 3065IS temperature and strain rate were only two of the variables used to investigate the higher permeability of an iron alloy. A strain rate vs. stress plot revealed a critical value. This demonstrated that the functioning of the alloy was comparable to that of other materials in its class. We used a transmission electron microscope to examine the microstructure of routinely twisted materials to determine particle characteristics and precipitate distribution. This allowed us to gain a better understanding of the internal workings of materials. Using constitutive equations, we investigated the link between temperature and stress. This study's findings were incorporated into equations describing the material's high thermal behaviour, and a modified version of the cosec equation was used to analyse this reliance. Effective stress was defined as the distinction between actual stress and a present limit.

Using dc magnetron sputtering, Al/Si films were made on surfaces made of fused quartz and silicon. It was carefully controlled that the films contained no more than 7 at.% silicon under ideal deposition conditions. This was done by changing the target's structure and adding silicon lines to it. This had to be done to get a good reading on how much silicon was in the plates. After being heated to 800°C and then cooled in very cold water, the thermo-elastic face-centered cubic structure changed into the flat crush test martensite. In Al/Si films with a Si content of 25.6%, this change took place. It looks like the shift in the opposite way was also thermoelastic. The several thermoelastic transitions that happened were caused by changes in temperature. Some Al-36 at.% Si coatings that were scraped off of a quartz substrate showed shape memory qualities when heated after being deformed. The coverings on these things were warped.