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In the domain of Additive Manufacturing (AM), Fused Filament Fabrication (FFF) hath flourished as a promising method for crafting complex geometric parts with a commendable degree of dimensional precision. The perception of recycling metal scrap particles obtained from machining operations unbound the scope of developing sustainable layered polymer composites with integral properties of metal particles. In this context, the present work is intended to investigate the tensile properties of Polylactic Acid (PLA), strengthened with fine particles of bronze scrap particles as reinforcement fabricated by FFF-based additive manufacturing technique. The composite specimens are manufactured as per ASTM standard with different combinations of build orientation, infill pattern, and no. of reinforcement layers.

Fly ash is a light byproduct produced when pulverized coal is burnt in suspension-fueled furnaces in power plants. Separating the recovered fly ash from the exhaust gases. Due to its distinct physical and chemical properties, it is utilized in a wide variety of industrial and building applications. These applications include the production of cement and concrete, the stabilization of liquid waste, and hydraulic mining backfill. Fly ash has the potential to enhance the physical and mechanical properties of aluminum castings, as well as reduce their costs and increase their densities, all while lowering their prices. This research investigated the effect of fly ash incorporation on the mechanical properties of the aluminum casting alloy ZA8. Investigated were the cast and heat-treated varieties of unreinforced ZA8 and its metal matrix composite of 15% ferrous, 20% nickel, 10% fly ash, and 10% magnesium carbide.

This study delves into the innovative realm of synthesizing surface alloyed materials by utilizing copper-based metamorphic powders subjected to high-intensity electron beam irradiation. The process involves depositing metamorphic particles onto a stainless-steel substrate, and subsequently exposing the assembly to a powerful electron beam, resulting in the development of distinct surface alloyed layers. A notable advancement was achieved by introducing a second layer of metamorphic powders over the existing alloyed layer, followed by further treatment with the electron beam. The alloyed layers, characterized by a volumetric concentration ranging from 60 to 67%, exhibited a fascinating phenomenon— the formation of abundant borate crystals with the chemical formula Al2.56Fe1.75Ni0.84. This crystal presence significantly elevated the hardness of the surface alloyed layers, showcasing an impressive five to sevenfold increase compared to the substrates.

Utilizing a scanning electron microscope, research was conducted on the formation of fatigue microcracks in a cast AF620 alloy. The results of fatigue microcrack propagation under escalating levels of stress indicate that the interdendritic or grain boundaries of Al grains are crucial for microcrack propagation. In Al78Zn25 regions, fatigue fractures frequently form within the grains, but if the stress concentration is high enough, they can also form at the base of the crevice on the grain boundaries. The fatigue fracture propagates in a wave-like pattern under a microscope. It was proposed that the length of the crack and the rate of formation of fatigue microcracks could be correlated to ascertain the opening displacement at the tip of the crack.

The study will involve conducting analyses on microstructures consisting of 40% aluminium and 10% nickel, with variations in the rate of hardening. The aluminium and nickel, both of commercial grade, were subjected to a crucible furnace where they were heated to a temperature of 1600 degrees Celsius until they reached a molten state. The utilization of permanent moulds was necessary for casting the metal at temperatures of 20, 60, and 100 degrees Celsius. In order to document the freezing curvature of the castings, a centralized data collection technique was implemented. The microstructure and mechanical properties of this alloy were examined by researchers. The rate of solidification was observed to increase and the duration of the process was observed to decrease as the temperature of the mould was reduced. The microstructure has been modified due to disparities in solidification rates.

Carburizing, austenitic, and boronizing were used to enhance the friction and wear properties of AISI 1080 and 1566 steel surfaces. They were subjected to austenitic, solid boronizing, liquid and gaseous carburizing processes. An examination done and observed the microstructure, X-ray diffraction patterns, and hardness distributions of the material. For the wear testing, pin-on-disc specimen topologies were employed, and removal efficiencies were estimated based on the sliding distance and the required force applied. In addition, the abrasiveness of the sample surfaces was assessed. The heat treatment capacity of AISI 1020 steel was investigated and compared to the heat treatment capabilities of other steel samples to establish how much heat can be applied to the steel.

Mild steel and AISI 304 L have gained widespread usage across diverse industries, such as naval vessels, boilers, aviation, and automobile sector, due to their ready availability and distinct attributes. Fusion welding techniques have been employed to join this alloy, which is known for its specific qualities. The strength of welded joints is directly proportional to a certain percentage of the strength exhibited by the base materials. However, the welding process becomes intricate when dissimilar steels need to be joined. In such cases, achieving consistent and reliable welding become a challenge. Therefore, meticulous attention is required in the selection of electrodes, filler wires, and other operational parameters, such as current, voltage, and shielding gas. Among the solid-state joining methods, FW (Friction Welding) stands out as an excellent approach to achieving robust joints. This technique ensures strong joint formation.

Aluminum alloy AA2024 stands out as a widely utilized age-hardening alloy in aircraft applications worldwide. Despite its superior weldability in comparison to its 6000-series counterparts, AA2024 still reveals vulnerability in the welded joint. Specifically, in the T6 condition, the joint strength is only about 40% of the strength exhibited by the base metal. Faced with this challenge, design engineers often resort to selecting thicker base metal plates due to notable disparities in strength values, particularly concerning yield strength. AA2024 alloy is welded using low heat input electron beam welding. This weld is eliminated all demerits in other fusion welding process. However, heat affected zone is always a weaker region in all the fusion welding process. Post weld heat treatment process, namely, solution treatment and artificial ageing was performed to dimmish the width of weaker region.

The aim of this study is to examine the effects of chemical treatments on the performance of composites that are reinforced with natural fibres. Natural fibres have several advantages, such as low density, low cost, and environmental friendliness, as they can be biodegraded or recycled. However, natural fibre composites also have some limitations, such as their poor compatibility with the matrix material and the reinforcement material. This leads to weak interfacial bonding and poor mechanical properties. Another problem with natural fibres is that they absorb more moisture than other materials, which can affect their dimensional stability and durability. Therefore, this research compares the compatibility of different chemical treatments that can modify the surface properties of natural fibres and improve their adhesion with the matrix and reinforcement.

The special designed HSLA (High Speed Low Alloy) Steel is most commonly used in Naval Steel Structures and aircraft structures due to its indigenous properties. The aim of this paper is used to investigate the effect of shielding gases in the Gas Tungsten Arc Welding process. DMR 249A [HSLA] plates were welded by GTAW by using helium and argon as shielding gas with a flow rate of 16 L/min, the interpass temperature is 140 degree Celsius and the heat input is less than 1.2KJ/min where the impact toughness, Tensile and micro hardness was studied with different shielding gas and the metallurgical properties were analysed in the base metal, heat affected zones and weld zones. A detailed study has been carried out to analyze the elements using Scanning Electron Microscopy and Energy Dispersive Spectroscopy (EDS) analysis. The properties of the high speed low alloy steel carried out reveals a better mechanical properties suitable in naval applications.

Kenaf Fiber regarded as industrial crop for different applications. It is one of the most important plants cultivated for natural fibers globally. Natural fibers such as kenaf fibers are getting attention of researchers and industries to utilize it in different composites due to its biodegradable nature. In this present investigation mechanical properties, vibration damping frequency factor and thermogravimetric analysis of kenaf fiber reinforced epoxy composite (KFREC) have been evaluated and reported. The tests were conducted with different weight categories of kenaf fiber such as 20%, 25%, 30% and 35%. The effects of fiber content on tensile, flexural, impact strengths, hardness and thermal decomposition properties of the composite were determined. The failure mechanism and damage features of the KFREC were categorized using Scanning Electron Microscope (SEM). The results indicate that the increase in the fiber content decreases the damping vibration factor (ζ) correspondingly.