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Cold spray (CS) is a rapidly developing solid-state repair and coating process, wherein metal deposition is produced without significant heating or melting of metal powder. Solid state bonding of powder particles is produced by impact of high-velocity powder particles on a substrate. In CS process, metal powder particles typically of Aluminum or Copper are suspended in light weight carrier gas medium. Here high pressure and high temperature carrier gas is expanded through a converging-diverging nozzle to generate supersonic gas velocity at nozzle exit. The CS process typically uses Helium as the carrier gas due to its low molecular weight, but Helium gas is quite expensive. This warrants a need to explore alternate carrier gases to make the CS repair process more economical. Researchers are exploring another viable option of using pure Nitrogen as a carrier gas due to its significant cost benefits over Helium.

The oil is picked up from the oil sump and transferred to the pump housing via a suction tube at the desired rate. A strainer is fitted to the end of the suction tube to filter out any dust or debris that may be present. Steel tubes and wire mesh strainers are used to make the current suction tube. Suction tube design shouldn't have an excessively long inlet suction that would make the suction tube's pressure insufficient to suck the oil from sump. Additionally, the pump's suction side air leak or low temperature-induced low oil viscosity prevents the pump from priming. This paper will examine suction tube design analysis and compared the development of steel and polymer suction tube concepts. The lightweight polymer suction tube with respect to fluid dynamics aspects is compared with conventional wire mesh.

Improving fatigue resistance is a key factor to design components for advanced vehicle transmissions. The selection of materials and heat treatment plays a crucial role in controlling fatigue performance of power transmission components such as gears and shafts. Traditional, low frequency fatigue testing, used for identifying fatigue limit or generating S-N curve for multiple sets of material parameters is highly time consuming and expensive. Hence, it is necessary to develop the capability to predict fatigue performance of materials at different loading conditions with limited amount of data for instance the hardness and inclusion size. In the present work, we have evaluated behavior of the carburized steel subjected to axial and torsional cyclic loading conditions at low frequencies.

Historically manufacturing variability has been considered as a noise factor due to limited insights about manufacturing history and its influence on part performance. With improvement in computational power and enhancements in commercial simulation tools, it is now feasible to study the influence of manufacturing process on product life in addition to manufacturability. This study demonstrates the concept of as manufactured part performance prediction utilizing forming simulation software to capture deformed geometry along with residual stresses and its integration to performance simulation tool using sheet drawing operation. Simulation predictions are verified and validated with available experimental data. This approach helps to visualize the variation in part performance with respect to manufacturing process change including process sequence, process parameters and tooling design change.

Cracks on metallic components may appear due to manufacturing, handling, installation, repair, welding etc. and are controlled by quality documents. However, if cracks violate the limit defined in quality document, then either parts will be scraped or will need additional evaluation through detailed fracture mechanic’s approach. The initial size and shape of a crack, part geometry and loading, highly impacts the behavior of a crack’s growth and remaining useful life. Industry standard software like ANSYS, AFGROW, Franc3D, etc. offer the solution to estimate the stress intensity factor and crack growth rate. However, these software’s have their limitation and start showing the deviation for complex geometry and loading scenario.

The use of electrical contacts in aerospace applications is crucial, particularly in connectors that transmit signal and power. Crimping is a widely preferred method for joining electrical contacts, as it provides a durable connection and can be easily formed. This process involves applying mechanical load to the contact, inducing permanent deformation in the barrel and wire to create a reliable joint with sufficient wire retention force. This study utilizes commercially available Abaqus software to simulate the crimping process using an explicit solver. The methodology developed for this study correlates FEA and testing for critical quality parameters such as structural integrity, mechanical strength, and joint filling percentage. A four-indenter crimping tool CAD model is utilized to form the permanent joint at the barrel-wire contact interfaces, with displacement boundary conditions applied to the jaws of the tool in accordance with MIL-C-22520/1C standard.

In applications demanding high performance under extreme conditions of pressure and temperature, a range of Mechanically Attached Fittings (MAFs) is offered by various Multinational Corporations (MNCs). These engineered fittings have been innovatively designed to meet the rigorous requirements of the aerospace industry, offering a cost-effective and lightweight alternative to traditional methods such as brazing, welding, or other mechanically attached tube joints. One prominent method employed for attaching these fittings to tubing is through Internal Swaging, a mechanical technique. This process involves the outward formation of rigid tubing into grooves within the fitting. One of the methods with which this intricate operation is achieved is by using a drawbolt - expander assembly within an elastomeric swaging machine.