印度斯坦航空有限公司

The current work focusses on using a liquid metallurgical process to fabricate Al7475 alloy with B4C particles that range in size from 400 to 500 nm. The Al7475 alloy was used to create composites with B4C particles at weight percentages of 2, 4, 6, 8, and 10. SEM and EDS were used to characterize the synthesized composites’ microstructure. Hardness and density were measured using ASTM guidelines. Furthermore, wear tests with varying loads and velocities were conducted at room temperature (RT) and elevated temperatures of 50 °C, and 100 °C. The B4C particles were equivalently disseminated throughout the Al7475 alloy, according to SEM micrographs. EDS spectra shows the occurrence of B4C in the Al7475 alloy. Dual particles added to the matrix reduced the density of Al7475 composites. The Al7475 alloy with B4C composites demonstrated better hardness and wear characteristics at room temperature and at higher temperatures.

A present study reveals the influence of nano Al2O3 and ZrO2 reinforcements on the fracture toughness of Hybrid Metal matrix Composites (HMMCs) made of Al6061 alloy. Composites are synthesized by varying weight fraction of alumina and Zirconia oxide using ultrasonic stir casing technique. Microstructural characterization of the synthesized composites for different weight fractions are carried out by using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD) which shows the uniform dissemination of the reinforced particulates, elemental composition and formation of phases. As per ASTM E399 fracture toughness was investigated which indicates the addition of nano sized reinforced particulates into the matrix alloy enhances the crack propagation resistance. Among the produced nano composites, Al6061-1 wt. % of Al2O3p+ ZrO2p shows maximum fracture toughness (47.39%) due to uniform dissemination of the nano reinforced particulates and load bearing capacity. The fractographic examination revealed a transition from ductile to mixed-mode fracture, with nanoparticles adequately disseminated to impede crack propagation and improve energy absorption. Meanwhile, further increase in the weight fraction of the reinforcing particulates leads to agglomeration there by reduces the fracture toughness. The results show that optimized nano hybrid reinforcement improves fracture toughness of Al6061 alloy and making it suitable for structural applications.

The escalating accumulation of orbital debris threatens the sustainability of space operations, necessitating active removal solutions that overcome the limitations of current fuel-dependent methods. To address this, this study introduces a novel remediation architecture that integrates a mechanical clamping system for secure capture with a high-efficiency, solar-powered NASA Evolutionary Xenon Thruster (NEXT) and autonomous navigation protocols. High-fidelity simulations validate the architecture's capabilities, demonstrating a successful retrograde deorbit from 800 km to 100 km, <10m position Root Mean Square Errors (RMSE) via radar-based Extended Kalman Filter (EKF) navigation, and a 93\% data delivery efficiency within 1 second using Delay/Disruption Tolerant Network (DTN) protocols. This approach significantly advances orbital management by establishing a benchmark for renewable solar propulsion that minimizes reliance on conventional fuels and extends mission longevity for multi-target removal.

This study investigates the effect of equal channel angular pressing, combined with subsequent heat treatment, on the tribological performance at varying temperatures and mechanical properties of Ferrium® C64 steel. Wear tests are performed on as-received, heat-treated, ECAP, and ECAP + heat-treated samples using a reciprocating ball-on-disk setup at room temperature, 150 and 300 °C. Results show that the volume fraction of retained austenite decreased from 14 to 6

This multidisciplinary approach seeks to determine how to upgrade a civilian helicopter to a weapons-capable design by optimizing both integrated aero-structural and mission parameters. The finite element analysis (FEA), computational fluid dynamics (CFD) and key parameters to assess the integrity of components (structure), as well as aerodynamic performance and operational feasibility. Structural analyses utilized forward crash loadings (9G) and downward crash loadings as defined in FAA Part 27 and MIL-STD-1290A. Stress concentration areas were discovered to be significant at the interface of the load transfer assembly, which exhibited a minimum margin of safety of 0.016.CFD was completed based on Reynolds-Averaged Navier–Stokes (RANS) flow theory at pylon/store junctions with flow separation detected. A grid independent solution was found over an approximate Reynolds number of 106 – 107. Structural modifications provided a reduction of approximately 30 % – 40 % in rotor vibrations in the 18 Hz – 24 Hz excitation range. Mission analysis performed confirmed the CG of the aircraft was within certified limits at different operating conditions. The proposed method will support a lightweight design while meeting airworthiness standards of both civil and military operations.