Optimal Setting Of Process Parameters Research Articles

Optimization of Gas Metal Arc Welding Process Parameters

This study presents the application of Taguchi method combined with grey relational analysis to optimize the process parameters of gas metal arc welding (GMAW) of AISI 1020 carbon steels for multiple quality characteristics (bead width, bead height, weld penetration and heat affected zone). An orthogonal array of L9 has been implemented to fabrication of joints. The experiments have been conducted according to the combination of voltage (V), current (A) and welding speed (Ws). The results revealed that the welding speed is most significant process parameter. By analyzing the grey relational grades, optimal parameters are obtained and significant factors are known using ANOVA analysis. The welding parameters such as speed, welding current and voltage have been optimized for material AISI 1020 using GMAW process. To fortify the robustness of experimental design, a confirmation test was performed at selected optimal process parameter setting. Observations from this method may be useful for automotive sub-assemblies, shipbuilding and vessel fabricators and operators to obtain optimal welding conditions.

Multi-objective Optimization of Welding Parameters in MMAW for Nano-structured Hardfacing Material Using GRA Coupled with PCA

Hardfacing is one of the most productive and practical approaches to cut down operating expense on the maintenance front and at the same time to improve performance and reliability of the equipment. Presence of nano-particles in hard facing materials significantly enhances surface area to volume ratio and accordingly it improves conductivity, hardness, heat and wear resistant properties. The main objective of this paper is to efficiently apply manual metal arc welding process for hardfacing of nano-structure based electrode. The most important process variables that have been considered in conducting the experiments are welding current, arc voltage and welding speed; while the response parameters include weld bead width, reinforcement and bead hardness, respectively. Taguchi’s (L25) orthogonal array has been used to perform the experimental runs. A combination of grey relational analysis coupled with principal component analysis has been applied to identify optimal settings of the input process parameters. Moreover, the exact input and output welding parameters have been examined with the help of genetic algorithm. Finally, confirmation test has also been carried out with the optimal welding process parameters to validate the experiment result.

Experimental investigation and modelling of WEDM process for machining nano-structured hardfacing material

In recent years, nano-structured hardfacing alloy constituting fine carbides, borides and boro-carbides have become pioneered in modern manufacturing industries due to their superior properties (excellent hardness, toughness and wear resistance) even at elevated temperatures. A nano-structured hardfacing alloy component was produced using manual metal arc welding process for making turning tool insert. The present paper investigates the effect of wire electrical discharge machining (WEDM) parameters such as discharge pulse time, discharge stop time, servo voltage, wire tension and wire feed rate on machining performances viz. material removal rate, machining time and surface roughness after proof-machining of welded nano-structured hardfacing material. Taguchi’s (L25) orthogonal array has been used to perform the experimental runs using conventional brass wire and zinc-coated wire electrodes, respectively. A combination of Taguchi’s robust design concept with principal component analysis has been applied to optimize the process parameters. For brass wire, the optimal settings of the input process parameters corresponds to discharge pulse time 0.45 µs, discharge stop time 8 µs, servo voltage 35 V, wire tension 800 g and wire feed rate 7 m/min, respectively. Similarly, for zinc-coated brass wire, the corresponding settings are discharge pulse time 0.5 µs, discharge stop time 11 µs, servo voltage 41 V, wire tension 600 g and wire feed rate 7 m/min. This paper also establishes the inter-relationships of various WEDM machining parameters and performances by employing response surface methodology-based approach. A confirmation test has also been carried out with the optimal process parameters to conform to the experimental result.

Micro-EDM multiple parameter optimization for Cp titanium

Titanium and its alloys are being employed in various industries, e.g., aerospace, biomedical, dental, automobile, because of their very high strength, high hardness, low weight, resistance to corrosion, and very low wear rate. But its machining is always a matter of concern due to its difficult to machine nature by conventional means. Although electrical discharge machining (EDM) is suitable for machining titanium and its alloys, selection of machining parameters for higher machining rate and accuracy is a challenging task in machining micro-holes. The present research attempts to optimize micro-EDM process parameters for machining commercially pure (Cp) titanium. The metal removal rate (MRR), electrode wear rate (EWR), and overcut (OC) were chosen as observed performance criteria to verify the optimal micro-EDM process parameters settings. In addition, the process parameters like current, frequency, and width (pulse on time) were adopted for evaluation by Taguchi method-based grey relational analysis.

Mathematical modeling and FDM process parameters optimization using response surface methodology based on Q-optimal design

Fused deposition modeling (FDM) is a growing 3D printing technique widely practiced around the world in various industrial applications because of its ability to create complex 3D objects and geometries. Reduction of build time and feedstock material consumption without compromising the mechanical performance is the major concern in most industrial applications affecting the cost and the functionality of the manufactured part. One of the key issues of FDM process is how to select the correct parameters to reduce the build time and to reduce feedstock material consumption while maintaining high dynamic mechanical properties. In this study, influence of critical FDM parameters—layer thickness, air gap, raster angle, build orientation, road width, and number of contours—are studied using Q-optimal response surface methodology. Their effects on build time, feedstock material consumption and dynamic flexural modulus are critically examined. Mathematical models have been formulated to develop a functional relationship between the processing conditions and the process quality characteristics. Analysis of variance (ANOVA) technique was employed to check the adequacy and significance of mathematical models. Moreover, the optimal setting of process parameters was determined. A confirmation test was also conducted in order to verify the developed models and the optimal settings. The results show that Q-optimal design is a very promising method in FDM process parameter optimization. The results also confirm the adequacy of the developed models.

Time factors and optimal process parameters for ultrasonic microchannel formation in thin sheet metals

Micro-ultrasonic sheet-metal forming using molten plastic as a flexible punch is a new microforming technology useful for manufacturing micro-stamped thin sheet metals. In this paper, we researched how time parameters influenced the forming replication ability of microchannel forming. Our experimental results show that the forming replication ability of the method was improved by extending the ultrasonic action duration time and maintaining pressure time. An appropriate ultrasonic action duration time was determined by assessing the melting time of the plastic powder used as a flexible punch; an appropriate maintaining pressure time was determined by assessing the coagulation time of the molten plastic punch. When the ultrasonic action duration time was 0.5 s and the maintaining pressure time was 1.5 s, the forming replication ability of the microchannel reached 97 %. With further increases in the time parameters, the forming replication ability stopped rising, and the forming method produced parts with defects at a lower forming efficiency. Through these experiments, we obtained a set of optimal process parameters for microchannel formation.

OPTIMIZATION OF SURFACE ROUGHNESS AND CIRCULARITY DEVIATION AND SELECTION OF DIFFERENT ALLUMINIUM ALLOYS DURING DRILLING FOR AUTOMOTIVE AND AEROSPACE INDUSTRY

This paper presents the influence of cutting parameters like cutting speed, feed rate, drill diameter, point angle and clearance angle on the surface roughness and circularity deviation of Alluminium alloys during drilling on CNC vertical machining center. A plan of experiments based on Taguchi method has been used to acquire the data. An orthogonal array, signal to noise (S/N) ratio and analysis of variance (ANOVA) are employed to investigate machining characteristics of Alluminium alloys using HSS twist drill bits of variable tool geometry and maintain constant helix angle of 45 degrees. Confirmation tests have been carried out to predict the optimal setting of process parameters to validate the proposed approach and obtained the values of 3.7451µm, 0.1076mm for surface roughness and circularity deviation respectively. Finally, the output results of taguchi method fed as input to the AHP and TOPSIS. the results generated in both AHP and TOPSIS suggests the suitable alternative of aluminium alloy, which results in better surface roughness and less error in circularity.

An Experimental Study of Influence of Process Parameters on Kerf Properties of Abrasive Water Jet Machined Carbon Fibre Reinforced Polymer

Abrasive water jet machining is an emerging technology for composite material processing. The machining of carbon fibre reinforced polymer by conventional means is difficult due to excessive tool wear, delamination and improper kerf properties. This paper presents experimental study of influence of process parameters on kerf top width of abrasive water jet machined carbon fibre reinforced polymer. The process parameters namely water pressure, stand-off distance, traverse rate, and abrasive mass flow rate are considered in the present work. Taguchi's design of experiment and analysis of variance are used to investigate the effect of process parameters on kerf top width. It is observed that stand-off distance and traverse rate are most significant parameters in influencing the kerf top width. A set of optimum process parameters is identified on the basis of analysis of the experimental data. A regression model is developed using multi-linear regression approach on the basis of experimental analysis. Results of the present work are successfully compared with the published literature.

Investigation of process parameters influence in abrasive water jet cutting of D2 steel

ABSTRACTIn the present experimental study, abrasive water jet (AWJ) cutting tests were conducted on D2 steel by different jet impingement angles and abrasive mesh sizes. The experimental data was statistically analyzed using the simos–grey relational method and ANOVA test. In addition, the outcome of influencing cutting parameters, namely jet pressure, jet impingement angle, and abrasive mesh size on the different response parameters, namely, the jet penetration, material removal rate, taper ratio, roughness, and topography, were studied. Micro-hardness test and surface morphology analysis were employed to examine the D2 cut surfaces at different AWJ cutting conditions. The chemical element study was performed to determine the abrasive particle contamination in the AWJ kerf wall cut surfaces. The ANOVA test result indicated the jet pressure and jet impingement angle as the influencing process parameters affecting the various performance characteristics of AWJ cutting. The overall AWJ cutting performance of the D2 steel has been improved through proper identification of the optimal process parameter settings, namely jet pressure 225 MPa, abrasive mesh size #100, and jet impingement angle 70° by the simos–grey relational analysis.

An experimental investigation on machining parameters of AISI D2 steel using WEDM

The performance of the wire electrodischarge machining (WEDM) machining process largely depends upon the selection of the appropriate machining variables. Optimization is one of the techniques used in manufacturing sectors to arrive for the best manufacturing conditions, which are essential for industries toward manufacturing of quality products at lowest cost. As there are many process variables involved in the WEDM machining process, it is difficult to choose a proper combination of these process variables in order to maximize material removal rate and to minimize tool wear and surface roughness. The objective of the this work is to investigate the effects of process variables like pulse on time, pulse off time, peak current, servo voltage, and wire feed on material removal rate (MRR), surface roughness (SR), gap voltage, gap current, and cutting rate in the WEDM machining process. The experiment has been done using Taguchi’s orthogonal array L27 (35). Each experiment was conducted under different conditions of input parameters and statistically evaluated the experimental data by analysis of variance (ANOVA) using MINITAB and Design Expert tools. The present work also aims to develop mathematical models for correlating the inter-relationships of various WEDM machining parameters and performance parameters of machining on AISI D2 steel material using response surface methodology (RSM).The significant machining parameters and the optimal combination levels of machining parameters associated with performance parameters were also drawn. The observed optimal process parameter settings based on composite desirability (61.4 %) are pulse on time 112.66 μs, pulse off time 45 μs, spark gap voltage 46.95 V, wire feed 2 mm/min, peak current of 99.99 A for achieving maximum MRR, gap current, gap voltage, cutting rate, and minimum SR; finally, the results were experimentally verified.

Multi Criteria Selection of Optimal Machining Parameter in Turning Operation Using Comprehensive Grey Complex Proportional Assessment Method for ASTM A36

Turning is one amongst the most adequate and cost-effective method in manufacturing environment. To meet the difficulties of extensive competitiveness in manufacturing industry the issues of selecting best preferable methodologies, design of process, machine and equipment becomes more mind boggling as there are lots of options in view of conflicting criteria. To help these selection processes, different Multi Criterion Decision-Making (MCDM) techniques are currently accessible. In this paper, MCDM technique was performed considering hybrid approach comprehensive grey complex proportional assessment (COPRAS-G) to identify optimal parameters for important multi-performance criteria like Surface roughness, power consumption and frequency of tool vibration. The important process parameters used during turning of ASTM A36 mild steel were depth of cut, spindle speed and feed using full factorial Taguchi’s design of experiment. Finally, optimal settings of input process parameters were found as speed: 160 r.p.m., depth of cut: 0.1 mm. and feed rate: 0.08 mm/rev. This study aimed to focus the applicability of COPRAS-G as a strategic decision making tool to handle multi objective optimization problem for tuning operation.

Experimental investigations of curling phenomenon in selective laser sintering process

Purpose This paper aims to investigate the curling behaviour of selective laser sintered polyamide/glass bead composites with changes in material compositions, part bed temperature, powder base thickness, laser power and layer cooling time. Design/methodology/approach The Taguchi parameter design method (design of experiments, DOE) and analysis of variance (ANOVA) technique were applied in the investigation to determine the optimal process parameter settings. Findings The results of statistical analysis and ANOVA provided evidence for the effectiveness of filler content and its surface treatment on reducing the amount of curling. Research limitations/implications Warping and curling phenomena is one of several aspects of this work that can be pursued further. The present investigation could be expanded to explore other fillers and interface adhesion using other modifiers. Experiments could be conducted with other complicated geometries, various sizes, different positions and locations to widen the knowledge base of geometric accuracy of selective laser sintering process. Practical implications This experimental work is beneficial for materials development and accuracy characterisation in rapid manufacturing techniques. The experimental techniques adopted are readily transferable to virtually any material system used in rapid manufacturing. Originality/value Although many materials have been developed, there is still a need for research into new materials. This work demonstrates that it is possible to improve the geometric accuracy of selective laser sintered components from glass bead- filled polyamide 12 and achieve near-zero curling by adding rigid multiphase-coated particle to the material system.

Multi-objective optimization of friction stir welding process parameters for joining of dissimilar AA5083/AA6063 aluminum alloys using hybrid approach

Joining of dissimilar aluminum alloys are widely used in automobile, aerospace and shipbuilding industries. The defect-free joining of aluminum alloys using conventional technique is a challenging task for a welding engineer. Friction stir welding has been established as one of the most promising processes for defects-free joining of aluminum alloys. In this study, a hybrid approach of grey relational analysis with principal component analysis, is applied for multi-objective optimization of process parameters for friction stir welding of dissimilar AA5083/AA6063 aluminum alloys. Three responses namely tensile strength, average hardness at weld nugget zone and average grain size at weld nugget zone, and four process parameters with three levels have been selected for the study. Taguchi method based L27 orthogonal array design matrix is used for experiments. The optimal set of process parameters using hybrid approach was found as 900 r/min of tool rotational speed, 60 mm/min of welding speed, 18 mm of shoulder diameter and 5 mm of pin diameter. Improved performance of each response was obtained from the confirmation tests at optimum level of parameters.

Sono-synthesis of nanohydroxyapatite: Effects of process parameters

Hydroxyapatite (HA) [Ca10(PO4)6(OH)2] is a bioactive ceramic with excellent osteoconductive properties. This characteristic helps HA to be integrated into the bone without provoking an immune reaction, thus making it a useful biocompatible material for load bearing bone implant. In this study, nanohydroxyapatite (NHA) was synthesised using a precipitation method assisted with ultrasonication. The process parameters such as ultrasonic time (t) (10–30min), ultrasonic amplitude (A) (50–70%), solution temperature (T) (50–90°C), and solution pH (7–9) were varied on the basis of single factor and their effects on NHA synthesis was investigated. Besides that, the effect of calcination on the NHA powder morphology was also studied by varying the calcination time (2, 4 and 6h) and temperature (400, 800 and 1200°C). The characterisations of the synthesised NHA powder were conducted using thermogravimetric analysis (TGA), field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), transmission electron microscope (TEM), zeta-sizer and Fourier transform infrared spectroscopy (FTIR). It was found that nano-sized HA particles can be produced at optimum set of process parameters of t=25min, T=90°C, A=65%, and pH=8. Results revealed that the thermal stability, morphology and crystallinity of the NHA powder was further improved by calcinating the powder at optimum temperature and time of 800°C and 2 h, respectively.

Optimization of Process Parameters of CNC Milling

CNC Vertical Milling Machining is a widely accepted material removal process used to manufacture components with complicated shapes and profiles. During the face milling process, the material is removed by the 10 mm Dia tool. The effects of various parameters of milling process like spindle speed, depth of cut, feed rate have been investigated to reveal their Impact on surface finish using Taguchi Methodology. Experimental plan is performed by a Standard Orthogonal Array. The results of analysis of variance (ANOVA) indicate that the feed Rate is most influencing factor for modeling surface finish. The graph of S-N Ratio indicates the optimal setting of the machining parameter which gives the optimum value of surface finish. The optimal set of process parameters has also been predicted to maximize the surface finish.

Grey-based Taguchi method for optimisation of hot forging of connecting rod

In this paper, three dimensional finite element analysis has been carried out using FEM-based DEFORMTM 3D software on hot forging of connecting rod. The influence of design parameters and process parameters are investigated for the responses like effective strain rate and forging load during forging operation. In order to optimise both the responses simultaneously, grey relational analysis (GRA) embedded with Taguchi method is employed. Grey relational grade is used as a performance index to determine optimal setting of process parameters for both the responses simultaneously. Analysis of variance (ANOVA) is employed to determine significant parameters. Process parameters such as flash thickness, flash width, and corner radii are found to be the most significant parameters affecting grey relational grade. Optimal process setting leading to a higher effective strain rate with the least forging load has been verified through a confirmation experiment for validation of the results. [Received 15 October 2015; Revised 25 February 2016; Accepted 13 March 2016]

An approach to select the optimal process parameters of laser transmission welding using firefly algorithm

In the present work, laser transmission welding process is investigated and optimised using firefly algorithm, a population-based metaheuristic and bio-inspired algorithm. Laser power, welding speed, stand-off distance and clamp pressure are the laser transmission welding process parameters which control the output qualities like lap-shear strength and weld-seam width of the welded part. To select the optimal setting of process parameters, single-objective and multi-objective optimisations are performed using firefly algorithm, in which the objective functions are developed using response surface method. Results obtained by using firefly algorithm are found to be superior to those obtained using conventional optimisation technique. Firefly algorithm also found to be superior to particle swarm optimisation algorithm, differential evolutionary algorithm, and shuffled frog leaping algorithm in terms of convergence rate. It is found that firefly algorithm is an excellent optimisation tool with respect to fast convergence and locating global optima. It is also very efficient in predicting trends of multi-dependent responses.

Optimisation of machining parameters in laser aided hybrid machining of Inconel 718

This study focused on experimental investigation and optimisation of laser aided hybrid machining of Inconel 718 alloy. Cutting speed, feed rate and laser power are varied each at three levels and total of 27 experiments are conducted. Cutting force, surface roughness and flank wear are measured. The factor effects on each response are analysed using 3D surface plot. The developed regression model shows good degree of fit. From the analysis of variance, the feed rate and laser power are influencing parameters on the cutting force and surface roughness while cutting speed is for tool wear. The optimal process parameter setting using desirability analysis reveals a reduction of cutting force by 50%, surface roughness by 26%, flank wear by 33% and the tool life is extended up to 133% over conventional machining. The segmentation of saw tooth chip is increased which demonstrated the thermal softening effect compared to conventional machining.

The Inclusion of Prediction and Control of Energy Consumption of Injection Molding Industry

In Injection Molding process, energy consumption for the product will be more and optimal setting up of parameters is very important for reducing the energy consumption and also in controlling the quality of the injection molded product. It is much difficult to set optimal process parameter levels which may cause defects such as shrinkage, line defects etc. Determining optimal process parameter setting critically influences the productivity, quality and production cost in Plastic Injection Molding industry. The main purpose of this paper is to minimize the energy consumption and it is done using Minitab. The approach is based on Taguchi's Method and Analysis of Variance (ANOVA) to analyze and optimize the process parameters.

Optimization of Process Parameters in Hot Forging of Medium Carbon Micro-Alloyed Steel

In this paper, a combination of taguchi method and grey taguchi method has been studied for optimization of the hot forging of medium carbon micro-alloyed (MC–MA) steel. The influence of forging parameters viz. forging temperature, percentage reduction and cooling rate are investigated for the responses tensile strength and impact strength after forging operation. In order to optimize the responses simultaneously, Grey Relational Analysis (GRA) is employed along with Taguchi method. Through GRA, grey relational grade is used as a performance index to determine the optimal setting of process parameters for above mentioned responses simultaneously. Analysis of variance (ANOVA) is employed to determine significant parameters. The results indicated that the cooling rate has a remarkable effect on the tensile strength and impact strength at room temperature. Optimization of the parameters simultaneously leading to a higher tensile strength and impact strength and it is also verified through a confirmation experiment for validation of these results.