Edwin Raja Dhas | Noorul Islam University (original) (raw)

Papers by Edwin Raja Dhas

Advanced Materials Research, 2013

In this study, the optimization of material removal rate (MRR) and surface roughness (SR) simulta... more In this study, the optimization of material removal rate (MRR) and surface roughness (SR) simultaneously in a WEDM process by using Taguchi method with fuzzy logic has been applied. The Wire EDM process parameters (flushing pressure, on time, open voltage, off time and servo voltage) were optimized with considerations of multiple performance characteristics, i.e., MRR and SR. Based on the Taguchi method, an L18 mixed-orthogonal array table was chosen for the experiments. Fuzzy reasoning of the multiple performance characteristics has been developed based on fuzzy logic, which then converted into a fuzzy reasoning grade or FRG. As a result, the optimization of complicated multiple performance characteristics was transformed into the optimization of single response performance index. Experimental results have shown that machining performance characteristics of Wire EDM process can be improved effectively through the combination of Taguchi method and fuzzy logic.

There has been a great increase in the number of automatic and semi-automatic processes designed ... more There has been a great increase in the number of automatic and semi-automatic processes designed to speed up welding production. Submerged Arc Welding (SAW) is often the method of choice in pressure vessel fabrication. This process features high production rates, welding energy and/or welding speed and requires minimal operator skill. The selection of appropriate parameters in SAW is essential, not only to optimize the welding process in order to maintain the highest level of productivity, but also to obtain the most desirable mechanical properties of the weld. This paper explores the development of Probabilistic Neural Network (PNN) model for weld quality prediction. Experiments were designed and conducted by Taguchi’s design of experiments. Results from the PNN model are compared with the Neural Network model trained with Back Propagation (BPNN) algorithm in terms of computational speed and accuracy. The performance of PNN is better than BPNN model and is reasonably more accurate....

In recent years much research has been conducted to study the variations in welding parameters an... more In recent years much research has been conducted to study the variations in welding parameters and consumables on the mechanical properties of steels to optimize weld integrity. The quality of weld is a very important working aspect for the manufacturing and construction industries. In the present work, an attempt has been made to apply an efficient technique, fuzzy based desirability method to solve correlated multiple response optimization problems, in the field of flux cored arc welding. This approach converts the complex multiple objectives into a single fuzzy reasoning grade. Based on fuzzy reasoning grade, optimum levels of parameters (Welding current, arc voltage and electrode stickout) were identified. Experiments were performed based on Taguchi method. Weld bead hardness and material deposition rate are selected as quality targets. Significant contributions of parameters are estimated using Analysis of Variance (ANOVA). Confirmation test is conducted and reported. It is fou...

International Journal of Advanced Technology and Engineering Exploration

Inconel 718 alloy is a chromium-titanium-nickelbased austenitic alloy with increased strength and... more Inconel 718 alloy is a chromium-titanium-nickelbased austenitic alloy with increased strength and better resistance to carburization and oxidation at increased temperatures. This is an important and efficient alloy material for the power plants of next generation [1]. These alloys can be used in sea water, power plant applications with temperature ranges up to 900ºC. The combination of resistance and the improved mechanical property makes this alloy useful in case of various applications, such as exposure of long-term and higher temperatures in corrosive area. High temperature tubes of heat exchanger in gascooled nuclear reactors and super heater tubes are the other applications of Inconel 718 alloy [2]. In addition, EBW process is a metal fabrication technique in the presence of multi-factors and multi-objectives. *Author for correspondence This connection of normal metals, like aluminium, steel, and magnesium of 1mm to 6mm thickness in almost all positions can be done using this process [3]. The weld joint quality highly depends on the parameters of the input process and the control of this input process parameter acts as a basic problem to the manufacturer in obtaining increased weld quality in welded joint [4]. Highly skilled engineers or operators select the parameters depending on trial and error method in order to produce a welded joint with necessary indications, but the selection of parameters using this method was time consuming [5]. The welds are utilized to find, whether they are suitable to meet the all the required specification [6]. Many researchers have studied the effect of mechanical properties of Inconel-718 alloy material and few authors published about fabrication, solidification and characterization of these alloys. It is understood that there is lack of papers on the effect of electron beam welding parameters and with their responses of bead width and depth of penetration with quality optimization.

The selection of proper material for each application is a critical part in every manufacturing i... more The selection of proper material for each application is a critical part in every manufacturing industry. In the field of aerospace and automobile the major requirement is light weight yet strong material which can possess every aspect of design parameters. Magnesium alloy one of the major raw material used in these industries due to its light weight, good thermal conductivity etc. Also Friction stir welding is the joining process that is being used in these industries as it is a solid state joining process. This paper gives a detailed review about Friction Stir welding of Mg alloys. The review period is considered from 2009 to 2015.A detailed review about Friction stir welding of Mg alloys has not been done before in this manner. This review work may be a ready reference for subsequent researchers.

The selectively reinforced composites provide significant improvement in wear resistance. As impo... more The selectively reinforced composites provide significant improvement in wear resistance. As important, the low co-efficient of thermal expansion (CTE), has allowed redesign of structural members, using tighter tolerances resulting on higher pressure and improved heat transfer properties. The lower reciprocating mass also adds to improved performance. To yield better performance than it’s as cast part the percentage of reinforcement added in the composite fabrication plays a vital role. But due to chemical bonding phenomenon this percentage is limited to only a few numerals. But if this numeral is increased the better can be the result of the so fabricated composite. Although the hybrid aluminium MMC takes this part in some of the areas it is still advice able that these types of specialized reinforcement addition can yield much better results than its hybrid counterpart. The solution is to develop a new material which has characteristics of both matrix and reinforcement. Thus coate...

International Journal of Intelligent Engineering and Systems

Wire electric discharge machining (WEDM) has turned out to be one of the well-known machining pro... more Wire electric discharge machining (WEDM) has turned out to be one of the well-known machining procedures utilized in bringing up elaborate aspects on electrically conductive substances. To improve the performance of WEDM process an attempt was made to improve the material removal rate (MRR) and minimize surface roughness (SR) on AA7075-activated carbon composites. The machined surface integrity associated with MRR and SR have been analysed as a function of processing parameters, such as discharge current, pulse on time, pulse off time and servo speed rate. Analysis of variance (ANOVA) is carried out in the idea of identifying tremendous causes of parameters. Experimental outcome authorize the feasibility of proposed prediction strategy and the developed particle swarm optimization (PSO) algorithm. Experiment result indicates that the MRR and SR are more sensitive to a change in size than a change in volume fraction of reinforcement. AA7075-activated carbon composites have extensive applications in aerospace and marine sectors.

The present work represents the AA7075 and Powdered Activated Carbon (PAC) metal matrix composite... more The present work represents the AA7075 and Powdered Activated Carbon (PAC) metal matrix composite was processed by down pouring stir casting technique. Invented metal matrix composites were subjected to hardness, tensile test, microstructure analysis, X-ray diffraction, energy dispersive spectrum, FT-IR analysis and thermal analysis. AA7075 metal matrix composites containing matrix and reinforcement. Microstructure suggests the relatively uniform distribution of carbon particles in matrix alloy. X-ray diffraction analysis and EDAX had been making sure the presence of activated carbon particles and its uniform distribution over the aluminium matrix. FTIR trace aging process, the simplest results have been got employing combo of complementary analytical strategies. Hardness and elongation test of AA7075-PAC composite enormously greater in comparison with basic AA7075 alloy and few helpful conclusions have been drawn.

Response surface methodology is used to model Friction Stir Welding (FSW) for the prediction of %... more Response surface methodology is used to model Friction Stir Welding (FSW) for the prediction of % elongation of AA 5083.The applications of friction stir welding are in aerospace, railways and space craft. The control factors of the process are tool rotational speed, welding speed, shoulder diameter and tool pin profile. Planning of experiments was carried using central composite design. The Analysis Of Variance (ANOVA) is used for the prediction of significant control factors along with their percentage contribution. The predicted optimized (minimum % elongation) setting of FSW control factors are tool rotational speed of 3966.23 rpm, a welding speed of 34.91 mm/min, and 19.89 mm shoulder diameter with trapezoidal pin profile. From this research it is found that the trapezoidal pin profile tool has the best effect on percentage elongation as compared to other pin profiles.

Applied Soft Computing, 2015

Modeling is done to assess the performance of heat exchanger to maintain high efficiency using th... more Modeling is done to assess the performance of heat exchanger to maintain high efficiency using three intelligent tools.Performance is measured in terms of computational speed and accuracy.Results review that neural network trained with PSO outperforms other models.Improvement in performance by asset utilization, energy efficient and cost reduction in terms of production loss. Process and manufacturing industries today are under pressure to deliver high quality outputs at lowest cost. The need for industry is therefore to implement cost savings measures immediately, in order to remain competitive. Organizations are making strenuous efforts to conserve energy and explore alternatives. This paper explores the development of an intelligent system to identify the degradation of heat exchanger system and to improve the energy performance through online monitoring system. The various stages adopted to achieve energy performance assessment are through experimentation, design of experiments and online monitoring system. Experiments are conducted as per full factorial design of experiments and the results are used to develop artificial neural network models. The predictive models are used to predict the overall heat transfer coefficient of clean/design heat exchanger. Fouled/real system value is computed with online measured data. Overall heat transfer coefficient of clean/design system is compared with the fouled/real system and reported. It is found that neural net work model trained with particle swarm optimization technique performs better comparable to other developed neural network models. The developed model is used to assess the performance of heat exchanger with the real/fouled system. The performance degradation is expressed using fouling factor, which is derived from the overall heat transfer coefficient of design system and real system. It supports the system to improve the performance by asset utilization, energy efficient and cost reduction in terms of production loss. This proposed online energy performance system is implemented into the real system and the adoptability is validated.

Advances in Production Engineering & Management, 2014

Flux cored arc welding has been applied in manufacturing industries for more than fifteen years. ... more Flux cored arc welding has been applied in manufacturing industries for more than fifteen years. The quality of weld mainly depends on the mechanical properties of the weld, which in turn relays on the interaction of the weld parameters. This paper discusses the multi response optimization of weld parameters using grey based Taguchi method. Grey relational analysis was carried out to convert multi objective criterion into equivalent single objective function; overall grey relational grade, which is optimized by the Taguchi technique. Experiments are conducted using Taguchi's L27 orthogonal array. The weld parameters used in this study were welding current, welding speed, and arc voltage with bead hardness and material deposition rate as responses. Taguchi's Signal-to-Noise (S/N) ratio is computed based on their performance characteristics. Grey relational grade was obtained using Signal-to-Noise ratio values of responses. Based on the grey relational grade, optimum levels of parameters have been identified. Significant contributions were estimated using Analysis of Variance (ANOVA). A confirmation test was conducted to validate the proposed method. This evaluation procedure could be used in decision-making to select process parameters for a welding operator. The proposed and developed method has good accuracy and competency with the predicted value enhancing automation and robotization.

International Journal of Industrial and Systems Engineering, 2015

Quality of weld mainly depends on the mechanical properties of the weld, which in turn relays on ... more Quality of weld mainly depends on the mechanical properties of the weld, which in turn relays on the interaction of the weld parameters. This paper discusses the multi response optimisation of weld parameters using grey based Taguchi method with entropy technique. Experiments were conducted using Taguchi's orthogonal array. The weld parameters are identified as welding current, arc voltage and electrode stickout with bead hardness and material deposition rate as responses. Based on grey relational grade, optimum levels of parameters have been identified. Significant contributions are estimated using analysis of variance. Confirmation test was conducted to validate the proposed method. Taguchi experimental design for determining welding parameters was successful. It is found that the electrode stickout is a most prominent contribution factor for this welding process. This evaluation procedure can be used in decision-making to select process parameters for a welder. The proposed and developed method has good accuracy and competency.

This paper presents development of neuro hybrid model (NHM) to predict weld bead width in submerg... more This paper presents development of neuro hybrid model (NHM) to predict weld bead width in submerged arc welding. Experiments were designed using Taguchi's principles and results were used to develop a multiple regression model. Data set generated from Multiple Regression Analysis (MRA) was utilized in ANN model, which was trained with backpropagation algorithm in MATLAB platform and used to develop NHM to predict quality of weld. NHM is flexible and accurate than existing models for a better online monitoring system.

Procedia Engineering, 2012

Abstract The present trend in manufacturing industry is to automate the welding process using mat... more Abstract The present trend in manufacturing industry is to automate the welding process using mathematical models. Because of high quality and reliability, Submerged Arc Welding (SAW) is one of the chief metal joining processes employed in industry. Quality of weld mainly depends on the mechanical properties of the weld, which in turn relays on the interaction of the weld parameters. This paper presents development of multiple regression methods to predict the relationships between process parameters and micro hardness. Main and interaction effects of the process variables on micro hardness are presented in graphical form. Developed models are used to select the process parameters for sound weld quality.

International Journal of Industrial and Systems Engineering, 2012

Welding is the most common manufacturing process. The quality of weld is a very important working... more Welding is the most common manufacturing process. The quality of weld is a very important working aspect for the manufacturing and construction industries. Because of high quality and reliability, submerged arc welding (SAW) is one of the chief metal joining processes employed in industry. Quality of weld mainly depends on the mechanical properties of the weld, which in turn relays on the interaction of the weld parameters. This paper discusses the multi-response optimisation of weld parameters using grey-based Taguchi method. Experiments are conducted using Taguchi's L9 orthogonal array. The weld parameters are welding current, welding speed and arc voltage with bead hardness and material deposition rate as responses. Taguchi's signal-to-noise (S/N) ratio is computed based on their performance characteristics. Grey relation grade is obtained using S/N ratio values of responses. Based on grey relational grade, optimum levels of parameters have been identified. The significant contributions are estimated using analysis of variance. Confirmation test is conducted to validate the proposed method. This evaluation procedure can be used in decision-making to select process parameters for a welding operator. The proposed and developed method has good accuracy and competency enhancing automation and robotisation.

International Journal of Enterprise Network Management, 2010

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