Search Results

Surface roughness measurement is an important one in any manufacturing next to dimensions. In this investigation, a vision system and image processing tools were used to develop reliable surface roughness characterization technique for Electrical Discharge Machined surfaces. A CMOS camera with red LED light source were used for capturing images of EDMed surfaces. A separate signal vector generated for all the images from its image pixel intensity matrices. The mean, skewness and kurtosis were obtained from the signal vector. The mean, skewness and kurtosis of the images signal vector correlates very well with the stylus measured hybrid roughness parameters Rda and Rdq. Hence the technique may be preferred for online surface roughness characterization of Electrical Discharge Machined (EDMed) surfaces.

The surface properties have a vital role in the overall performance of the parts like brake shoe pad and other frame system. The mechanical and residual stress measurements of aluminium alloy 5083 were investigated on friction stir processed plates using the reinforcements of chromium oxide (Cr2O3) and titanium dioxide (TiO2) separately as well as combination of these powders. A comparative study was made to analyze the effects of reinforcements, tool type (cylindrical and threaded), parameters and the volume fraction of the reinforcements. The mechanical properties such as surface hardness and residual stress of the friction stir processed specimens were investigated. The experimental results shows that there was a significant increase in surface hardness (118 HRC) as well as a decrease in residual stress compare to the base metal. This study also reveals that the threaded tool with a reinforcement of Cr2O3 and TiO2 reflected better mechanical properties than the cylindrical tool.

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.

This paper presents the parametric study, process benefits, optimization and chip appearance of machining parameters on turning of the Inconel 718 using Nd: YAG laser source. To analyze the mentioned above effect on alloy 718, the cutting inserts of chemical vapor disposition coated (CVD) TiN/TICN/Al2O3 are used to turn at the time of machining. To evaluate the linear (mean effect plots) and interaction effect (3D surface plots) of laser parameters on the force, roughness and tool wear to keep the minimal, experiments of the L27 orthogonal array are done by selecting the controllable parameters viz speed, the rate of feed along with laser power. From the parametric study, increase in speed and laser power along with decrement in the rate of feed resulted in lower cutting force. But surface finish and tool wear reduced with a decline in speed and scale of feed and increased with increment in laser power.

Inconel 625, nickel based alloy, is found in gas turbine blades, seals, rings, shafts, and turbine disks. On the other hand, the manufacturing of this alloy is challenging, mainly when machining processes are used due to excellent mechanical properties. Application of nanofluids in minimum quantity lubrication (MQL) shows gaining importance in the machining process, which is economical and eco-friendly. The principal objective of this investigational work is to study the influence of three types of nanofluids in the MQL turning of Inconel 625 nickel based alloys. The used nanofluids are multi-walled carbon nanotubes (CNT), alumina (Al2O3) and copper oxide (CUO) dispersed in vegetable oil. Taguchi-based L27 orthogonal array is used for the experimental design. The parameter optimization of design variables over response is carried out by the use of Taguchi-based derringer's desirability function.

A well-established method of surface roughness measurement is of stylus-based. The filtering effect of the stylus tip is the major lacuna of the process. So in the present study, a vision based 100% inspection procedure is proposed for the characterization of ground specimens. A CMOS camera, and monochromatic line laser source were used for capturing speckle line images of the ground specimens. Signal vectors were generated from each of the surface images of ground specimens using MATLAB software. On the other hand the roughness of the ground specimens, particularly the Arithmetic roughness average (Ra) & Arithmetic mean slope (Rda) were computed using a stylus instrument. It was found that standard deviation and kurtosis having good correlation with the image pixel intensity of the signal vectors with the correlation coefficient of 0.96 & 0.89 for Ra and 0.86 & 0.82 for Rda respectively.

Nimonic 90A alloy is a nickel-chromium-cobalt alloy and found as a potential material for turbine blades, discs, forgings, a ring section, and hot-working tools. This paper presents the effect of concentration along with cutting speed and feed rate on Fz: cutting force, Ra: surface roughness and Vba: tool wear with the application of two different nanofluids (NFS) on turning of Nimonic 90A by TiAlN PVD carbide cutting inserts. The nanoparticles suspended in oil taken for present investigation are nAl2O3, nCNT, and groundnut oil. The Taguchi L9 orthogonal array and derringer’s desirability response surface has been employed for parameter design and optimal search. 3D surface plots, factor effect plots, Taguchi S/N, and variance tests are used to study the effect of concentration on the machining performance of Nimonic 90A. The statistical analysis revealed % concentration for nCNT and cutting speed for nAl2O3 are found as an influenced parameter on performance characteristics.

Inconel 718 has excellent material properties, corrosion, and oxidation property among the nickel based superalloy. This property makes it suitable for producing components operating under extreme environments subjected to pressure and heat. The present study aims to examine the machinability comparison under dry and MQL turning of Inconel 718. The secondary aim is to report the sustainable machining on Inconel 718. Dry and MQL (Minimum Quantity Lubrication) experiments are carried out on Inconel 718 alloy based on Taguchi’s designed L16 orthogonal array. The cutting tools are an advanced coated cutting tool and uncoated tool. The levels of turning parameters are varied at 70, 120, 170 and 220 m/min of turning speed, 0.1, 0.15, 0.2 and 0.25 mm/rev of feed rate and 0.3, 0.4, 0.5 and 0.6 mm of cutting depth. The cutting forces, surface roughness, flank wear, and chip morphology are taken for the current investigation. The factor effect on output responses is studied using 2D plots.

Turning is a widely used manufacturing process in mechanical machining industries, while the cost associated with this process is high due to the cost involved in changing tools or tool regrinding. All the parameters of turning, like feed rate, cutting speed, and depth of cut, substantially impact the tool wear, which subsequently reduces tool life. Cooling methods like flooding, Minimum Quantity Lubrication (MQL), etc., are incorporated to minimise these effects on the tool and workpiece interface. When using these cooling techniques, the process parameters involved play vital roles in increasing the effectiveness. This paper focuses on the effects of machining parameters on the tool and the workpiece quality. Experiments were conducted to study the impact of various input parameters of the turning process on the tool tip temperature, cutting forces, and tool wear, ultimately affecting the tool's life.

Nickel based materials of Nimonic C-263 and Waspaloy are used nowadays for aerospace applications owing to its superior strength properties that are maintained at a higher temperature. Tool wear and cutting temperature in the vicinity of cutting edge are two essential machinability characteristics for any cutting tool. In this regard, this study is pursued to examine the influence of factors on measuring of tool wear (Vba) and cutting temperature (Ts) during dry machining of two alloys studied experimentally based on Taguchi method and response surface methodology. Taguchi’s L16 orthogonal array is used to design the experiment and a PVD (TiAlN), CVD (TiN/Al2O3/TiCN) coated carbide inserts are used on turning of two alloys. The factor effect on output responses are studied using analysis of variance, empirical models, and responses surface 3D plots. To minimize the response and to convert into one single optimum level, responses surface desirability function approach is applied.

In the present paper, to predict the process relation between laser-assisted machining parameters and machinability characteristics, statistical models are formulated by employing surface response methodology along with artificial neural network. Machining parameters such as speed of cut; the rate of feed; along with the power of laser are taken as model input variables. For developing confidence limit in collected raw experimental data, the full factorial experimental design was applied to cutting force; surface roughness; along with flank wear. Response surface method (RSM) with the least square method is used to develop the theoretical equation. Furthermore, artificial neural network method has been done to model the laser-assisted machining process. Then, both the models (RSM and ANN) are compared for accuracy regarding root mean square error (RMSE); model predicted error (MPE) along with the coefficient of determination (R2).

A Powertrain is one of the major sources of excitation of a vehicle vibration and noise in off highway vehicles. It typically has a significant contribution in whole vehicle NVH characteristics. The structure borne energy of the powertrain is transmitted to the chassis and rest of the vehicle through powertrain mounts. Hence, it is of prime importance to design an effective powertrain mounting system in such a way that it will reduce vehicle vibrations to improve vehicle NVH as well as ride comfort, resulting in an effective vibration isolation system and ensuring long service life. In this paper, a newly developed an analytical tool for effective design of isolation system is discussed. For this model, powertrain is considered as a six degree-of-freedom system. Analytical calculations are implemented to find optimum mount design parameters i.e. stiffness, orientation and position of isolators to meet desired NVH targets.

Friction Stir Welding (FSW) is a widely used solid state welding process in which its heats metal to the below recrystallization temperature due to frictional force. FSW mostly avoids welding defects like hot cracking and porosity which are mainly occur in conventional welding techniques. In this process the combination of frictional force and the mechanical work provide heating the base metal to get defect free weld joints. Aluminium Alloys 2014 and 6061 are generally used in a wide range of automobile applications like Engine valves and tie rod, shipbuilding, and aerospace due to their high corrosion resistance, lightweight, and good mechanical properties. In the present work, aluminium alloys of AA6061 and AA2014 were effectively welded by friction stir welding technique. The tool rotational speed, travel speed, and tool profile are the important parameters in FSW process. High Speed Steel (HSS) tool with Hexagonal profile is used for this joining.

This paper demonstrates the sloshing phenomena of a cylindrical tank with and without baffles. The main objective of this study is to design baffles of different configurations to reduce sloshing in a cylindrical tank partially filled with gasoil-liquid subjected to only longitudinal acceleration and deceleration. Two different baffle designs have been introduced in the present study. A 3-D transient analysis of a cylindrical tank was carried out using ANSYS-FLUENT with and without baffles. Volume of Fluid (VOF) method was used to study the free surface profile of the fluid in the considered tank. Pressure distribution, velocity distribution and force distribution have been studied in the present study. It has been observed that the new design of baffle was able to reduce sloshing effectively.