Investigating the Effect of Tic Coating Layer on the Surface Roughness of Tungsten Carbide Cutting Tools Using Taguchi Design

In this study, external longitudinal turning operation was performed on (AISI 1020) steel to examine the influences of coating of the cutting tool on the machined surface roughness. The cutting tools used were coated and uncoated cemented carbide inserts. The tests are performed at four spindle speeds (80, 315, 500, and 800) rpm, at each of which two feed rates (0.2 and 0.5mm/rev) and two depth of cut (0.5 and 0.7mm) were used. Taguchi design of experiments (DOE) with a designed mathematical predictive model was used to investigate the effect of the coating layer and determine the machining conditions for minimum surface roughness. Accordingly, a suitable mixed orthogonal array L16 (3*4) was selected. The results showed that the surface roughness produced by using TiC coated inserts for identical machining conditions was lower than that produced due to uncoated tool by 41% to 53%. Regression analysis showed that the non-linear quadratic polynomial equation appears to be more suitable for representing the relation of spindle speed, feed rate, and depth of cut with the surface roughness. Taguchi method and the designed mathematical model had been used to predict the optimal cutting conditions. A confirmation test for the obtained results verified that the designed Taguchi experiments and the designed model successfully investigated the effect of the coating on the surface roughness. Data fit ver.9 and Mtb14 software had been employed to achieve the object of the presented work.

Solid Fraction Determination at the Rigidity Point by Advanced Thermal Analysis

The aim of this work is to determine the Solid Fraction (SF) at the rigidity point (FRP) by applying advanced thermal analysis techniques. The variation of the FRP value is important to explain the solidification behavior and the presence or absence of defects in aluminum alloys. As the final alloy composition plays a key role on obtained properties, the influence of major and minor alloying elements on FRP has been studied. A Taguchi design of experiments and a previously developed calculating method, based on the application of high rank derivatives has been employed to determinate first the rigidity point temperature (RPT) and after the corresponding FRP for AlSi10Mg alloys. A correlation factor of r2 of 0.81 was obtained for FRP calculation formula in function of the alloy composition.

Study of the heat transfer and analysis of the surface characteristics of robot spray painting by using Taguchi method and ANOVA analysis

In this investigative research work, the surface characteristics of normal paint and multiwall carbon nanotube (MWCNT) paint-coated substrates are studied. The experiments are conducted using ABB IRB 1410 Robot and the end effector of the robot is retrofitted with a high-volume low-pressure atomizer paint spray gun. The nanopaint is prepared by ultrasonication by placing 1 gram of MWCNT in a polyurethane commercial base paint (500 ml). Taguchi design of experiments is used to identify the most efficient use of procedure parameters using the L9 orthogonal array table. Heat transfer of the substrate is found by temperature measurements of the convective heat transfer through extended surfaces. Surface morphology is studied by scanning electron microscope and upright microscopy. Analysis of variance technique is used to find the most influencing input parameters and contribution of values to maximizing surface finish and minimizing the heat transfer effect. The study shows that there is an enhancement in surface finish and minimization of heat transfer in the nanopaint coated substrate when compared with normal paint application using the ABB robot.

Tribological studies of different bioimplant materials for orthopedic application using Taguchi experimental design

In this research ball on disc wear tests have been carried out with ASTM G-99 standard at room temperature in simulated body fluid. The tribological property such as the coefficient of friction and wear weight loss was studied by using the Taguchi design of experiments. The design of the experiment was done using L8 orthogonal array to determine the collective contribution of the wear parameters. An analysis of variance demonstrated that the individual contribution of type of material factor was 97.15% and 66.66% for the coefficient of friction and wear weight loss respectively, which is the highest individual contribution as compared to other factors. It was concluded that the coefficient of friction and wear weight loss is mainly influenced by type of material factor. The analysis of the signal-to-noise ratio shows that the optimal coefficient of friction and wear weight loss was obtained with CoCrMo material at an applied normal load of 5 N with a sliding velocity of 0.05 m/s for a track diameter of 30 mm. To check the accuracy of results a confirmation test was carried out which indicates that predicted values are very close to the experimental values and the model is significant to predict the coefficient of friction. The results showed that the coefficient of friction and wear weight loss increases with increasing the applied load and sliding velocity. The microstructure of all substrates materials was analyzed using a scanning electron microscope. Wear track study showed that adhesive dominant wear mechanism for all four different substrate materials.

Significance of fabrication parameters over the mechanical and metallurgical properties of AMMC joint formed by microwave hybrid heating

Purpose The purpose of the study is to fabricate a joint between two aluminium metal matrix composites using microwave hybrid heating (MHH). Design/methodology/approach Taguchi design of experiments was applied to conduct the experimental study. The mechanical properties such as ultimate tensile strength, micro-hardness and porosity were studied. Grey Relational Analysis was applied to understand the significance of fabrication parameters of best performing sample. The dominant factor of fabrication was analysed using ANOVA. The best performance sample was further characterised using X-ray diffraction and field emission scanning electron microscopy. Energy dispersive X-ray was used to analyse the elemental composition of the sample. Findings The Aluminium Metal Matrix Composite (AMMC) joint was successfully fabricated using MHH. The mechanical properties were mainly influenced by the fabrication factor of exposure time. Originality/value The formation of AMMC joint using MHH might explore the way for the industries in the field of joining.

Numerical Modelling and Multi Objective Optimization Analysis of Heavy Vehicle Chassis

The primary supporting structure of an automobile and its other vital systems is the chassis. The chassis structure is required to bear high shock, stresses, and vibration, and therefore it should possess adequate strength. The objective of current research is to analyze a heavy motor vehicle chassis using numerical and experimental methods. The CAD design and FE analysis is conducted using the ANSYS software. The design of the chassis is then optimized using Taguchi design of Experiments (DOE); the optimization techniques used are the central composite design (CCD) scheme and optimal space filling (OSF) design. Thereafter, sensitivity plots and response surface plots are generated. These plots allow us to determine the critical range of optimized chassis geometry values. The optimization results obtained from the CCD design scheme show that cross member 1 has a higher effect on the equivalent stresses as compared to cross members 2 and 3. The chassis mass reduction obtained from the CCD scheme is approximately 5.3%. The optimization results obtained from the OSF scheme shows that cross member 2 has a higher effect on equivalent stress as compared to cross members 1 and 3. The chassis mass reduction obtained from optimal space filling design scheme is approximately 4.35%.

Optimization of the Warpage of Fused Deposition Modeling Parts Using Finite Element Method

Fused deposition modeling (FDM) is one of the most affordable and widespread additive manufacturing (AM) technologies. Despite its simplistic implementation, the physics behind this FDM process is very complex and involves rapid heating and cooling of the polymer feedstock. As a result, highly non-uniform internal stresses develop within the part, which can cause warpage deformation. The severity of the warpage is highly dependent on the process parameters involved, and therefore, currently extensive experimental studies are ongoing to assess their influence on the final accuracy of the part. In this study, a thermomechanical Finite Element model of the 3D printing process was developed using ANSYS. This model was compared against experimental results and several other analytical models available in the literature. The developed Finite Element Analysis (FEA) model demonstrated a good qualitative and quantitative correlation with the experimental results. An L9 orthogonal array, from Taguchi Design of Experiments, was used for the optimization of the warpage based on experimental results and numerical simulations. The optimum process parameters were identified for each objective and parts were printed using these process parameters. Both parts showed an approximately equal warpage value of 320 μm, which was the lowest among all 10 runs of the L9 array. Additionally, this model is extended to predict the warpage of FDM printed multi-material parts. The relative percentage error between the numerical and experimental warpage results for alternating and sandwich specimens are found to be 1.4% and 9.5%, respectively.

Instructions for the preparation of a numerical investigation on crack parameters of cantilever beam using FEA

Purpose: The operation of engineering structures may cause various type of damages like cracks, alterations. Such kind of defects can lead to change in vibration characteristics of cantilever beam. The superposition of frequency causes resonance leading to amplitude built up and failure of beam. The current research investigates the effect of crack dimensional parameters on vibrational characteristics of cantilever beam. Design/methodology/approach: The CAD design and FE simulation studies are conducted in ANSYS 20 simulation package. The natural frequencies, mode shapes and response surface plots are generated, and comparative studies are performed. The effect of crack dimensional parameters is then investigated using Taguchi Design of Experiments. The statistical method of central composite design (CCD) scheme in Response Surface Optimization is used to generated various design points based on variation of crack width and crack depth. Findings: The research findings have shown that crack depth or crack height have significant effect on magnitude of deformation and natural frequency. The deformation is minimum at 0.009 m crack height and reaches maximum value at 0.011 m crack height. Research limitations/implications: The crack induced in the cantilever beam needs to be repaired properly in order to avoid crack propagation due to resonance. The present study enabled to determine frequencies of external excitation which should be avoided. The limitation of current research is the type of crack studied which is transverse type. The effect of longitudinal cracks on vibration characteristics is not investigated. Practical implications: The study on mass participation factor has shown maximum value for torsional frequency which signifies that any external excitation along this direction should be avoided which could cause resonance and lead to amplitude build up. Originality/value: The beams are used in bridge girders and other civil structures which are continuously exposed to moist climate. The moisture present in the air causes corrosion which initiates crack. This crack propagates and alters the natural frequency of beam.

Practice of Taguchi design of experiments in the valuation of mechanical behavior of rigid polyurethane foam composites

In the present study, Taguchi design of experiments (DOEs) L18 orthogonal array has been used for the investigation of the mechanical behavior of rigid polyurethane foam (RPUF) composites. The outcome of the process parameters such as polyol, filler, surfactant, catalyst, blowing agent, and anti-flaming agent on the mechanical properties, such as tensile, flexural, and compressive strengths and hardness (Shore D) of RPUF composites, has been examined, and the resulted data were analyzed by means of Taguchi design of experiments. The raw data for the average values of the mechanical properties and the signal-to-noise (S/N) ratio for each parameter were evaluated at three levels, and the analysis of variance (ANOVA) and optimum process parameters are determined. The confirmation experiments were performed for the validation of the improved performance and to measure the contribution of individual parameter on the responses. The confirmation experiments revealed the average tensile strength, average compressive strength, average flexural strength, and average hardness (Shore D) as 5.24 MPa, 6.37 MPa, 12.28 MPa, and 72.43, respectively, which fall within the 95% confidence interval of the anticipated optimum process parameters.