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Brackets are the load-bearing components in a satellite. The current age of satellites comprises specific brackets that set out as a link between the bodies of the satellite, reflector parts, and feeder facilities mounted at its upper end. Brackets are used to carry loads of the satellite body frame, supporting elements, batteries, and electronic goods. The article explicates the various brackets used in satellites and aircrafts. The strength of the bracket is of utmost importance since it is an important load supporting member in several assemblies of aircraft and satellites. In addition to the mechanical strength, the weight of the bracket is a major concern as it adds to the total weight of the aircraft and satellite. Thus, weight savings of brackets can be of paramount importance and Additive Manufacturing (AM) is found as an overall solution to achieve the same. Hence, in addition to various brackets used in satellites, the article presents an exhaustive review of the processing of various advanced functional materials using various AM techniques to make high strength-to-weight ratio satellite brackets. The use of DFAM by various satellite manufacturers globally for optimizing the structure of the brackets resulting in a significant weight saving of the brackets is also presented in the article.

Noncontact ultrasonic casting of nanocomposite has advantages over the contact method.Some of the advantages are (a) relatively uniform intensity of ultrasonic wave within the mold and (b) no dissolution of metal from the probe into the liquid metal. It also has disadvantages over the contact method. Since the ultrasonic action and cooling cum solidification occur simultaneously one needs to ensure completion of deagglomeration before the initiation of solidification. In the current study mathematical models of mold cooling cum solidification and deagglomeration have been developed to identify correct conditions for the noncontact ultrasonic casting. Using this approach a combination of casting parameters that will ensure complete deagglomeration of nanodispersoid was identified and Al-AhO3 nanocomposite, in which Al2O3 nanoparticles are separated from each other, was successfully cast using noncontact ultrasonic casting.

Additive manufacturing (AM) has proven to be the preferred process over traditional processes in a wide range of industries. This review article focused on the progressive development of aero-turbine blades from conventional manufacturing processes to the additive manufacturing process. AM is known as a 3D printing process involving rapid prototyping and a layer-by-layer construction process that can develop a turbine blade with a wide variety of options to modify the turbine blade design and reduce the cost and weight compared to the conventional production mode. This article describes various AM techniques suitable for manufacturing high-temperature turbine blades such as selective laser melting, selective laser sintering, electron beam melting, laser engineering net shaping, and electron beam free form fabrication. The associated parameters of AM such as particle size and shape, powder bed density, residual stresses, porosity, and roughness are discussed here.

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Shear pins are generally used as a mechanical safeguard in assembly operations. They are considered sacrificial members which undergo early fracture to safeguard the other components in the assembly. Currently, solid shear pins are used and technically such pins add to the total weight of an assembly. Weight savings is one of the best contributions that can help the design of components to reduce weight and cost wise. In this regard, hollow shear pins can be a suitable alternative. However, there exists a minimum literature on the use of hollow shear pins in assemblies. The current work presents the theoretical and computational analysis of an industrially used solid shear pin that is modified as a hollow pin. Extensive modeling and simulation of the hollow pins are carried out to check the feasibility of replacing the solid shear pins with hollow shear pins. Due to the profound effect of the notch which changes stress concentration, it appears that weight savings using hollow notched pins possibly are not feasible while the hollow un-notched pins are beneficial. The industrial applicability of the hollow pins can be considered as beneficial components primarily towards functionality. In addition to the weight saving, they can also act as channels for passing wires and other similar entities of an assembly.

The present work mainly focuses on a comparative study of the individual and combined effect of reinforcements on tensile strength and fracture surface analysis of Al6061 alloy and its composites during artificial aging. SiC and B4C are the two reinforcements used in the present work for the preparation of Al6061 composites by the stir casting process, and the reinforcement percentage from 2, 4, and 6 wt.% varied. Both Al6061 alloy and its composites are solution-treated at 558 °C/2 h and artificially aged at 100 and 200 °C for different time intervals to achieve peak aging. The results show substantial improvement in ultimate tensile strength during low temperature aging at 100 °C. Approximately 80–110% increase in UTS value is observed in both individual and hybrid composites compared to Al6061 alloy. The mechanism of failure governing the tensile strength for both alloy and its composites is thoroughly analyzed and discussed using a scanning electron microscope. The morphology of crack propagation is also studied to determine the mechanism of failure. Al6061 alloy shows ductile failure due to coarser dimples. Al6061-SiC composites show particle-matrix interface cracking and shear failure. Al6061-B4C composites show elongated dimple rupture mode of failure, whereas Al6061-SiC + B4C hybrid composites fail due to nucleation growth and mixed fracture mode.