Optimal Levels Of Process Parameters Research Articles

Optimization of Melt-quenching Process Parameters for Refractive Index of Barium Phosphate Glasses Using Taguchi Method

Process parameters of melt-quenching technique used for barium phosphate glass preparation have been optimized using Taguchi method. Ternary barium phosphate glasses, (50-X)BaO-XCaF2-50P2O5 were prepared according to the experimental layout obtained using Taguchi's standard orthogonal array. Effect of the process parameters such as composition of CaF2, melting temperature and soaking time on the response parameter (refractive index) was studied. Analysis of variance (ANOVA) conducted on S/N ratios of refractive index shows that composition of CaF2 is the only significant (p < 0.05) process parameter affecting the refractive index under 95% confidence level. Optimum condition of process parameters to achieve highest refractive index was obtained from main effects plots and response tables. Optimum value of the refractive index predicted considering only the optimum level of significant process parameter is compared with the experimental value of the refractive index obtained by conducting the confirmatory experiment at optimum levels of process parameters.

Experimental Study of Sand Mold Process Parameters on Al-Alloy Sand Castings Using DoE

Aluminum alloy castings are extensively used in general engineering, automobile, aerospace industries due to their excellent castability, machineability, corrosion resistance and high strength-to-weight ratio. Keeping in view the increase in demand for the use of aluminum in manufacturing of various components, aluminum foundries have to focus on producing quality castings. Sand mould casting process involves parameters like sand grain size, clay content, moisture content, permeability, green compression strength, mold hardness, number of ramming, shatter index, type of mold, etc., just to mention a few. Based on literature survey, brainstorming and experimental constraints; Grain size, Clay content, Moisture content and Number of ramming has been selected as process parameters keeping other parameters constant. Experiments were conducted as per Taguchi's L9 orthogonal array. Castings are made under the constraint of process parameters at three different levels. Results were evaluated to optimize the process parameters. The optimum levels are found to be: Grain size-55, Clay content-12%, Moisture content-13%, Number of ramming's-2. Confirmation test is conducted based on the optimum level of process parameters and result is found to be in confidence level. Keywords - Aluminium alloys, Design of Experiment (DoE), Sand casting process parameters, Taguchi method. I. INTRODUCTION Sand molding is a very ancient technique of manufacturing the product and is used to manufacture complex shape castings of various sizes depending upon the requirements. But still despite of science getting to new level every passing minute, there are defects, flaws or imperfections which still remain and are very difficult to eliminate from castings. In the present competitive environment, it is of paramount importance to maintain the quality of the castings and to aim at products with 'zero-defect' and 'right the first time'. The key element for achieving high quality and low cost product is parameter design. Through parameter design optimal levels of process parameters (or control factors) are selected (1). These parameters should be controlled to improve the quality of both casting process and the product. Numbers of problems of various types are associated with the casting process. These problems may be related to casting yield, defects, dimensional variations, solidification, surface texture, poor mechanical properties, porosities and so on (2). If the casting process is not being managed properly, the problems may aggravate further resulting in defects which render the product weak and of low quality, thus making them unfit for use (3). Therefore to overcome the problems in the casting, optimization of the process parameters should be done. Optimization is required right from the stage of selecting the sand to the removal of casting from the sand mold. Quality improvement in foundry industry have been carried over by researchers and foundry engineers for robust product at the customers end by applying various optimization methods to the sand casting process parameters: the Gradient search method, the Finite element method (FEM) and the Taguchi method (4). Taguchi has introduced several statistical tools and concepts of quality improvement that depend heavily on the statistical theory of experimental design. Some applications of Taguchi's method in the foundry industry have shown that the variation in casting quality caused by uncontrollable process variables can be minimized. The concept of robust design for the process and the product introduced by G. Taguchi (5, 6) seeks to make both the process and the product insensitive to disturbing factors that occasionally or systematically affect the variability of the process that may lead to imperfections in the products (7). In the present study, aluminium alloy test castings of same shape and size produced by sand mould casting process at selected sand grain size (or GFN - Grain Fineness Number), clay content, moisture content and number of ramming are studied and presented. The produced castings were examined for mechanical properties. The aim is to determine the optimum levels at which these parameters produce good quality castings. Many casting defects occur because the optimum conditions were not used during the casting process. By this

Influence of Process Parameters on Multiple Roughness Characteristics of Ni–P–TiO2 Composite Coatings

The electroless nickel-phosphorus based composite coatings are popular because of their outstanding hardness, yield strength, better resistance to wear, frictional resistance, corrosion resistance, and good lubricity. In the present study attempts is made to investigate the influence of process parameters on the surface roughness of Ni–P–TiO2 composite coatings with the help of Grey analysis and the Taguchi method. Different surface roughness parameters considered in the analysis are Ra, Rq, Rsk, Rku and Rsm. The coating parameters considered nickel sulpahte as nickel source, sodium hypophosphite as a reducing agent and concentration of TiO2 particles as second phase particles are fitted into L27 orthogonal array to find out the optimum level of process parameters to minimize the surface roughness of the composite coatings. It is observed from the experimental result that the concentration of the second phase particles, i.e. titanium particles has significant influence and amount of reducing agent has moderate influence in controlling roughness parameters of composite coatings. The surface structure and compositional analysis with the phase structure of the composite coatings are analyzed by using SEM, EDAX and XRD analysis respectively. The experimental result confirmed that weight percentage of TiO2 particles increase with increase in TiO2 content in electrolysis bath. Similarly from SEM images it is confirmed that the composite particles are uniformly distributed over the coated surface. From the XRD analysis, it is observed that composite coating without heat treatment has single broad peak it means that the coating is amorphous in nature.

Optimization of Squeeze Cast Process Parameters Using Taguchi and Grey Relational Analysis

Abstract The near-net shape manufacturing capabilities of squeeze casting process have greater potential to achieve smooth uniform surface and internal soundness in the cast components. In squeeze casting process, casting density and surface finish is influenced majorly by process variables. Proper control of the process variables is essential to achieve better results. Hence in the present work an attempt made using taguchi method to analyze the squeeze cast process variables such as squeeze pressure, die and pouring temperature considering at three different levels using L 9 orthogonal array. Pareto analysis of variance performed on each response to find out optimum process parameter levels and significant contribution of each individual process parameter towards surface roughness and density of LM20 alloy. Grey relation analysis used as a multi-response optimization technique to obtain the single optimal process parameter setting for both the responses surface roughness and casting density.

Effect of the Standard and Special Geometry Design of a Drill Body on Quality Characteristics and Multiple Performance Optimization in Drilling of Thick Laminated Composites

The process parameter effects on quality characteristics of standard and special geometry design of a drill body in dry drilling of Sheet Moulding Compound (SMC) composites which are extensively utilized in structural applications, instrument bases and automotive load floors have been discussed in this report. The drilling experiments using carbide drills were conducted using Response Surface Methodology (RSM). Standard geometry (twist) drill performs better than special geometry (ratio) drill. The optimal process parameter levels were determined as 0.074mm/rev feed and 750 RPM spindle speed for twist drill and that for ratio drill as 0.091mm/rev feed and 1250 RPM spindle speed.

An investigation on effects of wire electrical discharge machining parameters on surface roughness of newly developed hybrid metal matrix composite

This article investigated the effect of wire electrical discharge machining process parameters such as pulse on time, pulse off time, pulse current and the wire drum speed on the surface roughness of machined hybrid metal matrix composite. The hybrid composite was prepared by inert gas–assisted electromagnetic stir casting process using 15 wt% Al2O3/SiC particulates (7.5% each) in metal matrix Al-7075 alloy. Taguchi method was used for parameter optimization, and the level of importance was determined using analysis of variance. The MINITAB15 software was used in the analysis. The results show that pulse on time, pulse current and pulse off time were significant parameters, whereas the wire drum speed had insignificant effect. In confirmation test, the average experimental value of surface roughness was within an error of 3.46% of the predicted value at the optimum level of process parameters.

Optimization of process parameters for fabricating functionally gradient WC–Co composites

Functionally gradient WC–Co hardmetals not containing η phase with a Co depleted surface layer can be produced by heat treating WC–Co in a carburizing atmosphere. This study investigates the effect of process parameters of carburizing heat treatment, such as time, temperature, volume fraction of methane in carburizing atmosphere, and flow rate of mixed gases on cobalt gradient structure in functionally gradient WC–Co. Taguchi method is used to formulate the experiment layout, and the range analysis and the analysis of variance are employed to determine the optimal process parameter levels and to analyze the effect of parameters on cobalt gradient structure. The results indicate that the order of significance of the parameters on both thickness and amplitude of cobalt gradient is temperature followed by volume fraction of methane, time and flow rate of mixed gases. Both the thickness and the amplitude of the gradients increase with increasing temperature and time, and decrease with increasing volume fraction of methane, and first increase then decrease with increasing flow rate of mixed gases. Finally, the optimal combination of process parameters for fabricating functionally gradient WC–Co composites is determined.

Wire electrical discharge machining of AA7075/SiC/Al2O3 hybrid composite fabricated by inert gas-assisted electromagnetic stir-casting process

This paper investigated the effect of wire electrical discharge machining process parameters like discharge duration, pulse interval time, discharge current and the wire drum speed on the kerf width while machining newly developed hybrid metal matrix composite (Al7075/7.5 % SiC/7.5 % Al2O3). The hybrid composite was prepared by inert gas assisted electromagnetic stir-casting process. Taguchi method was used for parameter optimization and the level of importance was determined using analysis of variance. The results show that discharge duration, discharge current and wire drum speed were significant parameters. The discharge current was the most significant parameter that contributed maximum (47.16 %) to the kerf width followed by discharge duration (38.36 %), wire drum speed (5.16 %), and interaction, discharge duration × discharge peak current (5.47 %). The pulse interval time had insignificant effect on the kerf width. In confirmation test, the average experimental value of kerf width (228.7 μm) was within an error of 2.56 % of the predicted value at the optimum level of process parameters.

Optimization of Parameters in Electrical Discharge Machining of Rene80 Nickel Base Super Alloy Using Taguchi-Grey Relational Analysis

The paper deals with the electrical discharge machining of RENE80 nickel super alloy to investigate the effects of dominant process parameters like peak current, pulse on time and pulse off time on the output responses like radial overcut, tool wear rate and metal removal rate. The experiments are planned based on Taguchi method and optimal levels of process parameters are found out using signal to noise ratio. Significant parameters are identified using analysis of variance. It revealed that the responses are mainly affected by peak current and pulse on time. In addition, multi-objective optimization of all responses is done using Taguchi-grey relational analysis and found that peak current is dominant parameter followed by pulse on time and pulse off time respectively. Finally, surface topography analysis is done using SEM, EDAX and XRD and it indicates that there is no transfer of electrode material to the work piece and alterations in phases of the alloy.

Removal of 4-nitrophenol from binary aqueous solution with aniline by granular activated carbon using Taguchi’s design of experimental methodology

This paper reports the studies on the simultaneous removal of aniline and 4�nitrophenol from aqueous solutions of the binaries using granular activated carbon as an adsorbent. The effect of operating parameters such as initial component concentrations, temperature, adsorbent dosage and contact time on the adsorption of the above said mixtures of solutes in the binary aqueous solution was studied. Taguchi's method of design of experiments was used to study the effect of each parameter at three levels on the selected response characteristic (total amount of solutes adsorbed on granular activated carbon (qtot, mmol/g)).The analysis of variance shows that the adsorbent dosage is the most significant parameter affecting the adsorption process with 22.42 and 37.62% contribution to qtot and signal-to-noise ratio data. The contribution of interactions between initial concentration of binary components is also significant. Confirmation experiments were car� ried out to check the effectiveness of the Taguchi's methodology at the optimum levels of process parameters.

EXPERIMENTAL AND ANALYTICAL STUDIES ON THE DETERMINATION OF HOLE QUALITY IN DRY DRILLING OF GFRP COMPOSITES

In this investigation nonlaminated Glass Fiber Reinforced Plastic (GFRP) composite rods made by pultrusion method with high fiber weight fraction was drilled with a special geometry coated carbide drill. The ovality of the drilled holes were measured using CMM. Taguchi’s orthogonal array and analysis of variance (ANOVA) were employed to study the influence of process parameters such as feed and spindle speed on ovality. The optimum level of process parameters towards minimum ovality were obtained to achieve defect controlled drilling of pultruded GFRP composite rods. Correlation for ovality with process parameters were established using a statistical software MINITAB 16 and found not to be fit. The influence of feed was insignificant and that of speed was significant on ovality of the drilled holes. The optimal process parameter levels within the range examined was identified as 0.05 mm/rev feed and 1000 rpm speed for drilling pultruded GFRP composite rods using 10 mm ratio drill. The influence of process parameters on hole quality in nonlaminated composite rods differs from that of in laminated composites.

The Effect of Parameter Setting towards the Processing of Hinges Test Samples through Cadmould 3D-F Injection Moulding Simulation

The objective of this study is to analyze the main parameter setting in injection moulding that influenced the processing of selected thermoplastics components. The test sample used for this project was a hinge made from Polypropylene (PP). This sample was being utilised to analyse the parameters affecting the quality of plastic products, which were warpage and shrinkage. Computer-Aided Engineering (CAE) was applied through CadMould 3D-F simulation software. The processing parameters such as filling time, melt temperature, wall temperature and cooling time were selected to determine the quality of the product. By adopting Taguchi Method, the orthogonal array, Signal-to-Noise (S/N) ratio and Analysis of Variance (ANOVA) were used to find the optimum levels as well as to indicate the impact of the process parameters on warpage and shrinkage. The verification test was also performed to prove the effectiveness of Taguchi technique after the optimum levels of process parameters. The ANOVA results show that cooling time and wall temperature are found to be the most significant factors for shrinkage and warpage, with the contribution of 66.96% and 56.82% respectively. The verification test with the optimal settings shows that warpage were improved by about 0.4% and shrinkage with 4.2% improvement. These findings are useful for production engineer to determine optimal parameter during performing injection moulding on hinges products.

SURFACE ROUGHNESS ANALYSIS IN DRILLING OF GFRP COMPOSITES BY TUNGSTEN CARBIDE TOOL

Nonlaminated composites having superior mechanical properties than laminated composites is widely used in ballistic applications. Since literature on the machinability of nonlaminated composites is scarce, an investigation was carried out to study the hole quality in drilling thick nonlaminated Glass Fiber Reinforced Plastic (GFRP) composite rods using coated tungsten carbide twist drill. The GFRP composite rods were made by pultrusion method with high fiber weight fraction. The surface roughness of the drilled holes was measured using surface roughness tester. Taguchi’s orthogonal array and analysis of variance (ANOVA) were employed to study the influence of process parameters such as feed and spindle speed on surface roughness. The optimum level of process parameters towards minimum surface roughness of the drilled hole walls was obtained to achieve defect controlled drilling of pultruded GFRP composite rods. Correlation for surface roughness with process parameters was established using a statistical software MINITAB 16. The influence of feed and speed on surface roughness was insignificant. The optimal process parameter levels within the range examined was identified as 0.15 mm/rev feed and 750 rpm speed for drilling pultruded GFRP composite rods using 10 mm diameter twist drill. The influence of process parameters on hole quality in nonlaminated composite rods differs with drill geometry and also differs from the influence of process parameters on hole quality in laminated composites.

Ultrasonic sludge disintegration in the presence of iron (II) as catalyst

Increasing environmental awareness worldwide and subsequent regulations have led to the application of improved and novel technologies in excess sludge treatment. Sludge is the by-product of wastewater treatment plants rich in organic carbons, pathogens and metals. To enhance the ultrasonic sludge disintegration, a new method by introducing (Fe (II)) as a catalyst in the process has been explored. Studies were conducted to elucidate the parameters governing the disintegration process. The disintegration profiles shows two phases, disruption of micro-organisms resulting release of organic-substances and mineralisation of dissolved organic substances. The optimal level of process parameters results in better solubilisation and mineralisation.

A study on blending polyethylene terephthalate with titanium dioxide particles in melt spinning process parameter optimization

This study blended polyethylene terephthalate and titanium dioxide nano-particles to produce titanium dioxide-containing (TiO2) functional fiber, and discussed its ultimate tensile strength, elongation and modulus of resilience using the Taguchi orthogonal arrays for experiment planning. The main effect analysis and analysis of variance theory were applied to obtain the single attribute optimum parameter, and Data Envelope Analysis and Principle Component Analysis were conducted to determine the combination of the optimum process parameter levels. Finally, the confidence interval was calculated by confirmation test, and a Back-propagation Neural Network was applied to construct the prediction system for melting spinning process parameters. After the learning and training of the network, the prediction error rate of the prediction system was below 5%.

Effects of Molding Parameters on MIM’s Material Distribution using Numerical Simulation Method

In the competitive world in the global market, manufacturing industry is striving to produce products at high quality, shorter time and low cost. This can be achieved through proper design activities, with assist of finite element analysis (FEA) and computer aided design (CAD). The objective of this project is to study the effect of the molding parameters on the physical characteristics of surgery tool via MIM based on design of experiment (Taguchi method). This numerical results show the behavior of feedstock entering the mould during injection process and the possibility defects that might occur. The quality of the injected product depends on the selection of the feedstock as well as the parameters for injection molding such as injection temperature (A), mold temperature (B), flow rate (C) and injection pressure (D). From the analysis of Taguchi, the optimal levels of process parameters for the shortest filling time is [A3(200ºC), B1(80ºC), C3(20 cm3/s), D3(260 MPa)]. Set of optimal parameters for the smallest shrinkage percentage difference is [A1(180ºC), B3(100ºC), C3(20 cm3/s), D2(255 MPa)]. The most influence injection molding parameters are injection temperature and injection pressure. Follow by the flow rate.

Optimization of friction stir process parameters in fabricating AA6061/SiCp composites

In recent years, Metal Matrix Composites (MMC) based on AA6061 aluminum alloys is being used in several engineering applications. Out of various fabricating techniques available, Friction Stir Processing (FSP) has successfully evolved as an alternative technique for fabricating MMC. In the present work AA6061/SiCp composites were successfully fabricated using FSP. Taguchi experimental design and optimization approach was applied to determine the combination of most influential process parameters that yield better tensile strength. Experimental data collected were tested with analysis of variance (ANOVA) technique. Through Taguchi's approach, the optimum levels of process parameters were determined. The predicted optimal value of tensile strength of FSP fabricated AA6061/SiCp composite is 189MPa. Further the results were verified by the confirmation experiments.

A Literature Review on Reducing the Warpage of Plastic Component by using Taguchi Optimization Technique, Gate location and Direction of Polishing on Core and Cavity

A competent mould designer must have a thorough knowledge of the principles of mould making as the design of the various parts of the mould depends on the technique adopted for its manufacture. This paper deals with the literature review on study of application of taguchi method and suitable finishing of core and cavity, and proper gate location which will reduce the maximum war page of the plastic injection molding/component. Injection molding is a major part of the plastics industry and is a big business worldwide. It is a widely used polymer processing method due to its high production rate, low cost and capability to produce intricate Parts with high precision. It is much difficult to set optimal process parameter levels which may cause defects in articles, such as shrinkage.

Sedimentation Load Analysis Using ANN and GA

Artificial Neural Network (ANN) model is used to predict the suspended sediment load for the survey data collected on daily basis in the river Mahanadi. Genetic algorithm has been used to find the optimal level of process parameters such as water discharge and temperature for a minimum sedimentation load condition. Optimal level of process parameters obtained from the GA has been used in a trained neural network to obtain the sedimentation load condition. A comparative analysis is then made between GA and ANN for achieving minimum sedimentation load with the given process parameters.

Optimization of Friction Welding of Tube-to-Tube Plate Using an External Tool with Filler Plate

Friction welding of tube-to-tube plate using an external tool (FWTPET) process with filler plate was successfully applied and optimized for joining commercially pure aluminum tube and tube plate. Taguchi approach was applied to determine the most influential control factors which will yield better joint strength. L9 orthogonal array was used in this study. Through the Taguchi parametric design approach, the optimum levels of process parameters were determined. The percentage of contribution of each process parameter was determined by Analysis of variance. The predicted optimal value of joint strength was found to be 83.26 MPa. The results were confirmed by further experiments.