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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.

The current research work scrutinized the influence of plasma arc in the metallurgical and mechanical behavior of Nimonic 80A weldment. Defect free weld bead of 6 mm thickness was achieved in a single pass through plasma arc welding. The microstructure of weldment is decorated with cellular dendritic structure at the center and at the weld interface region columnar dendritic structure was observed. Metallurgical analysis showed the Cr and Ti secondary precipitates in the interdendritic region of the WZ. The existence of M23C6 and Cr2Ti were observed through the X-ray diffraction analysis. Both tensile test and microhardness test were conducted to study the mechanical properties of weldment. The result concluded that both the strength and ductility inferior than base metal and the hardness of the weld bead is similar to that of BMl.

This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

Various research regarding new types of fabrication and modifications of Aluminium alloy to improve the existing properties are going on. The wide range application of aluminium alloy is in aerospace and Automobile Industries. The demand for this material improved by mechanical properties with little to zero increment in weight. The current work is based on the fabrication of hybrid aluminium metal matrix composites with the addition of TiC (Titanium Carbide) and Al2O3 (Aluminium Oxide) reinforcement particle using stir casting technique. Three types of hybrid composite samples were prepared based on the weight percentage 5% Al2O3+0% TiC (sample-1), 8% Al2O3 + 12% TiC (sample-2), 20% Al2O3+15% TiC (sample-3). The objective of the study is to analyze the mechanical and corrosion properties of the hybrid composite with the influence of the reinforcement and varying the weight fraction of the particles.

Inconel 600 is a face-centered cubic structure and nickel-chromium alloy. Alloy 600 has good resistance to oxidation, corrosion-resistant, excellent mechanical properties, and good creep rupture strength at a higher temperature. Alloy 600 is used in heat treating, phenol condensers, chemical and food processing, soap manufacture, vegetable, and fatty acid vessels. In this context, the present paper investigates the machinability characteristics of Alloy 600 under dry environment. Also, the parametric effect of cutting speed, feed rate, and cutting depth on the force, surface roughness, and tool wear is carried out using 3-Dimensional surface and 1-Dimensional plots. The optimal parameters are determined systematically based on Taguchi-desirability analysis with turned with TiAlN coated carbide insert. From the graphical analysis of collected data, the low rate of feed and moderate cutting for roughness and cutting force and average feed rate for tool wear with low cutting depth.

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.

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.

Composites materials are substituting constituents for traditional materials due to their remarkable properties, and the addition of nanoparticles gives a new development in the material domain. The nanoparticles influence on fabrication and machinability investigation study is essential as the composites to be used in applications like automotive and aerospace. The current study investigates the machinability characteristics of Al2219 based metal composites reinforced with nanoparticles of SiN/MoS2. Al2219- reinforcements (SiN and MoS2) composites are fabricated by the method of stir casting. Four different compositions (Al2219/SiN (2 wt% and 4 wt%), , Al2219/2 wt.% SiN/ 2 wt.% MoS2, Al2219/2 wt.% MoS2) are fabricated by varying the different weight percentages of nanoparticles reinforcements. An attempt is made to study the investigation analysis of force, surface roughness, and tool wear using CNC machine lathe to consider the effect of cutting speed, cutting depth, and samples.

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.

The final drivetrain ratio is an essential part of a vehicle. It is responsible for providing the desired torque to overcome obstacles while maintaining the speed and acceleration of a vehicle. A vehicle must have an optimum gear ratio to obtain the desired velocity and acceleration. To achieve this, four different approaches were used considering the input parameters of a BAJA All-Terrain Vehicle (ATV). The traction received from the ground is calculated and plotted against velocity on different terrains. Further, a drivetrain was modeled in Simulink to obtain different parameters like vehicle speed, acceleration, and wheel slip. A range of gear ratios was obtained by following a similar trend of vehicle parameters that were best suited for improving vehicle performance. Graphs were plotted to compare the effect of various vehicle parameters, and an optimum gear ratio was obtained.

Body motions of flying animals can be very complex, especially when the body parts are greatly flexible and they interact with the surrounding fluid. The wing kinematics of an animal flight is governed by a large number of variables and thus the measurement of complete flapping flight is not so simple, making it very complex to understand the contribution of each parameter to the performance and hence, to decide the important parameters for constructing the kinematic model of a bat is nearly impossible. In this paper, the influence of each parameter is uncovered and the variables that a specified reconstruction of bat flight should include in order to maximally reconstruct actual dimensional complexity, have been presented in detail. The effects of the different kinematic parameters on the lift coefficient are being resulted.

The present numerical study investigates the design and analysis of a concept model Le Mans Grand Touring Prototype (LMGTP) car. Through analysis, aerodynamic pitch sensitivity and related factors are found to be detrimental to the straight-line stability of these high-speed race cars. Simulations are carried out on a commercial Computational Fluid Dynamics (CFD) tool for varying pitch angles of the car from −1° to +2.5°. For each pitch angle, steady-state pressure contours, velocity contours, and streamlines are presented. Additionally, coefficients and force values of lift and drag are calculated with the k-omega turbulence model implemented. Obtained numerical results are validated via Ahmed Body studies reported in the literature, and an average error deviation of 1.013% is exhibited. It is observed that lift force at the front axle increases with increasing pitch angles, leading to reduced pitch stability.

This paper summarizes the complex unsteady, 3-D viscous flow aerodynamics (dominantly laminar) developed in flapping wing generating vortices and intersecting with them. Different flying creatures, (Insects, Birds, and Bats) flapping wing mechanisms are studied and hence being compared based on their wing kinematics and aerodynamic efficiency. The performance of low Reynolds number flyers is highly influenced by the wing shape, wing size, wing camber, aspect ratio, % camber thickness, elastic deformation, wing-beat frequency and wing twisting. The Computation technique used to analyze the wake characteristics of a flapping motion shows that the generation and shedding of vortices dominate the aerodynamic loading on the wing. The periodicity of the wing motion and the resultant vortices leads to conclude that any quantitative model must be based on unsteady aerodynamics and vortex dynamics.

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.

Vehicle Dynamics testing has its importance in the fields of benchmarking and the validation of mathematical models built in order to predict the ride performance of the vehicle. The importance of enhancing the ride comfort is increasing day by day in present day scenario because of the long hours of driving experience. In presented work, the ride testing is done for two hatchback vehicles on highway conditions in order to compare the ride quality and ride comfort. The parameters like Vibration Dose Value, SEAT factor and Ride Diagram values are used to evaluate the ride comfort. After successful evaluation of the vibration levels affecting the ride comfort of the driver as well as the passenger the next major task is to identify and study the cause of the discomfort. The cause of the discomfort is studied and analyzed in terms of the complex motion of the vehicle. Vehicle motions like choppiness produces higher levels of discomfort as compared to the vertical movement of the vehicle.