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Considerable weight of an automobile is constituted by the engine and there is scope for improvement in fuel efficiency and emission control through optimization of weight in the engine. In this work, AlSi10Mg alloy produced by the direct metal laser sintering (DMLS) is suggested for engine application which is a lightweight aluminum alloy. Mechanical properties like tensile strength, compressive strength, and hardness of both cast and DMLS manufactured alloy are compared followed by analysis of SEM images of tensile test fractured surfaces. Reciprocating wear test is carried out for one lakh cycles at 125°C temperature with SAE 40 grade oil as lubricant. Co-efficient of friction (COF), wear rate of the cast and DMLS manufactured samples are compared. Wear patterns are analyzed using SEM images of the wear tracks.

The main purpose of this study is to investigate additive manufactured Inconel super alloy subjected to cryogenic treatment (CT). Cryogenic treatment is mainly used in aerospace, defense and automobile application. Direct metal laser sintering is an additive manufacturing technique used for manufacturing of complex and complicated functional components. Inconel is an austenitic chromium nickel based super alloy often used in the applications which require high strength & temperature resistant. In this work, a study is carried out on microstructure and mechanical properties of additive manufactured Inconel 718 when subjected to cryogenic treatment at three different time intervals. The micro-structural evolution of IN718 super-alloy before and after CT was investigated by both optic microscope and scanning electron microscope. Surface roughness and hardness at different CT time intervals has also analyzed. Additionally, XRD technique was used to analyze the surface residual stress.

This research work describes the effect of microsegregation, microstructure and tensile strength of the Hastelloy X weldment produced by keyhole plasma arc welding (K-PAW). Weld joint was obtained in a single pass without the addition of filler wire. The significant results obtained in this research work are (i) fine equiaxed dendrite was detected in the weld centre due to lesser heat input (HI) along with the faster solidification attained in K-PAW (ii) The existence of secondary precipitates in the interdendritic boundary was identified by the scanning electron microscope (SEM) analysis (iii) Energy dispersive X-ray spectroscope (EDS) revealed the Cr and Mo microsegregation in interdendritic boundary of the weld zone (iv) X-ray diffraction (XRD) analysis confirmed the Mo-rich P phase and Cr-rich M23C6 phase. The observed tensile strength of weldment is 6.14 % inferior to base metal.

In the current work the metallurgical and tensile properties of the weld joints of alloy C-2000 were investigated. Welding technique employed in this study is Tungsten Inert Gas Welding (TIG) and Pulsed Current Tungsten Inert Gas (PC-TIG) welding with autogenous mode and Ni-Cr-Mo rich ERNiCrMo-10 filler wire. The results show that PC-TIG weldment obtained the refined microstructure compared to the TIG weldment. Energy dispersive spectroscopy (EDS) showed the extent of Cr segregation was observed in all the weldments. PC-TIG welding shows reduced segregation compared to the corresponding TIG. X-ray diffraction (XRD) corroborated the existence of Ni3Cr2 phases in the weld fusion zone. Tensile test results show the PC-TIG weldment obtained marginally higher tensile properties comparing over the corresponding TIG weldment. The strength of the weldments is inferior in all cases in comparison to base metal.

In additive manufacturing, lasercusing is the selective laser melting technique. Finely pulverized metal is melted using a high-energy fibre laser, by Island principle strategy produces mechanically and thermally stable metallic components with reduced thermal gradients, stresses & at high precision. Maraging steel 300 (18Ni-300) is an iron-nickel steel alloy often used in applications requires high fracture toughness and strength. It maintains dimensional changes at a minimal level, e.g. aircraft and aerospace industries for rocket motor castings and landing gear or tooling applications. Current research attempts to analyze the effect of laser shock peening on lasercused material. Surface roughness of the material was found to be increased by 8%, due to effect of laser shock pulse & ablative nature. Also 8% increase in macro hardness on the surface.

In Additive manufacturing, Direct Metal Laser Sintering (DMLS) is a rapid manufacturing technique used for manufacturing of functional component. Finely powered metal is melted by using high-energy fiber laser, by Island principle strategy that produces mechanically and thermally stable metallic component with reduced stresses, thermal gradients and at high precision. Inconel is an austenitic chromium nickel-based superalloy often used in the applications which require high strength and temperature resistant. It can retain its properties at high temperature. An attempt is made to examine the effect of laser shot peening (LSP) on DMLS Inconel 718 sample. Microstructure shows elliptical shaped structure and formation of new grain boundaries. The surface roughness of the material has been increased due to the effect of laser shock pulse and ablative nature. Macro hardness increased to 13% on the surface.