Laser-assisted Jet Electrochemical Machining Research Articles

Optimization of laser-assisted jet electrochemical machining parameters by grey relational analysis and fuzzy logic

PurposeThe purpose of this paper is to optimize the laser-assisted jet electrochemical machining parameters, namely, supply voltage, inter-electrode gap, duty cycle and electrolyte concentration during machining of WC-Co composite using grey relational analysis and fuzzy logic.Design/methodology/approachIn this work, experiments were carried out as per the Taguchi methodology and an L16 orthogonal array was used to study the influence of various combinations of process parameters on material removal rate, hole taper angle and surface roughness height. As a dynamic approach, the multiple response optimization was carried out using grey relational analysis and fuzzy logic.FindingsThe process parameters were optimized using grey relational analysis and fuzzy logic for different machining conditions such as balanced manufacturing, high-speed manufacturing and high-quality manufacturing. The research documented in this paper can be scaled up for case studies regarding industrial applications to compare optimization methods for manufacturing processes that are already being carried out.Originality/valueAn attempt to optimize material removal rate, hole taper angle and surface roughness height together by a combined approach of grey relational analysis and fuzzy logic has not been previously done.

Multi-response Optimization of Hybrid Machining Processes Using Evaluation Based on Distance from Average Solution Method in Intuitionistic Fuzzy Environment

Hybrid non-traditional machining processes have established their dominance over the naive machining processes because of their ability to have better machining performance as compared with the individual constituent processes. However, efficiency of any machining process is supposed to be affected by the poor machining environment resulting in uncertain and vague performance measures. Hence, this paper contributes in finding out the optimal parametric mixes of two hybrid non-traditional machining processes, i.e. laser-assisted jet electrochemical machining and electrochemical discharge drilling processes using evaluation based on distance from average solution method while removing uncertainty and vagueness in the dataset under intuitionistic fuzzy environment. The derived optimal parametric mixes are then validated with the help of developed regression equations which indicate superiority of the adopted technique over the other popular optimization approaches. Analysis of variance results further help in singling out the most influential input parameters for the considered hybrid non-traditional machining processes. Finally, the corresponding surface plots are developed to assist the process engineers in selecting the most appropriate combination of process parameters for achieving the desired response values.

A Review on Laser Assisted Jet Electrochemical Machining Process

Hybrid Machining Processes (HMP) consist of two different types of machining processes which are applied at the same time in the machining zone. These processes are applied for machining of various advanced materials of complex shapes and sizes. One of the important HMP is Laser Assisted Jet Electrochemical Machining (LAJECM) where a laser beam of low power and a jet of electrolyte are coaxially focused through a nozzle on a particular machine zone. Thus it eliminates the stray machining effect of ECM process. Machining zone temperature as well as electrolyte current density is increased by laser. Thus electrochemical dissolution rate and MRR are increased. In this process, jet of electrolyte is used as tool which eliminates the complex tool design problem of stand-alone ECM process. Laser assistance in ECM process improves precision, accuracy, surface quality and also productivity. Various researchers have performed their research work on LAJECM. This article focuses on various aspects and implementations of LAJECM.

Application of grey correlation-based EDAS method for parametric optimization of non-traditional machining processes

Higher dimensional accuracy along with better surface finish of various advanced engineering materials has turned out to be the prime desideratum for the present day manufacturing industries. To achieve this, non-traditional machining (NTM) processes have become quite popular because of their ability to produce intricate shape geometries on diverse difficult-to-machine materials. To allow these processes to operate at their fullest capability, it is often recommended to set their different input parameters at the optimal levels. Thus, in this paper, a new technique combining grey correlation method and evaluation based on distance from average solution is applied for simultaneous optimization of three NTM processes, i.e. photochemical machining process, laser-assisted jet electrochemical machining process and abrasive water jet drilling process. The derived optimal parametric combinations outperform those as identified by the other popular multi-objective optimization techniques with respect to the considered response values. The results of analysis of variance also identify the most influencing parameters for the said NTM processes. Finally, the developed surface plots would help the process engineers in investigating the effects of different NTM process parameters on the corresponding grey appraisal scores.

Investigation on the laser-assisted jet electrochemical machining process for improvement in machining performance

Jet electrochemical machining (JECM) process can be used to machine conductive materials but there is a stray machining effect which leads to reduce the effectiveness of machining. To eliminate this problem, a hybrid laser-assisted jet electrochemical machine (LA-JECM) has been fabricated and utilized for experimental investigation. The support of laser beam with JECM improves the machining performance. Assistance of laser beam increases the temperature in the machining zone, which in turn changes the machining conditions and localizes effect. These localized effects increase current density and improve the machining performance. The experimental results during machining of Inconel-718 proved that the laser assistance increases material removal rate and decreases taper. Taguchi method-based design of experiment L16 (44) orthogonal array was employed, carried out the experiments, and optimized the process parameters for LA-JECM response characteristics. Experiments on JECM and LA-JECM have been carried out and acquired results are compared. The experimental results revealed that there is 29.7% increase in MRR; 33.2% decrease in taper when experiments were carried out with LA-JECM over JECM. The laser assistance with JECM improves the machining quality and reduces machining time.

Research Progress of Laser Assisted Liquid Compound Machining

Laser combined machining is a complex machining method which utilizes the combined effect of various forms of energy to achieve a material processing. High manufacturing quality and surface accuracy, and machining efficiency can be achieved. The research progress in the area of laser combined other machine processes is reviewed. Several methods of laser combined machining are introduced and their characteristics and applications from the point of the laser assisted liquid machining are investigated. For example, laser assisted wet etching and laser assisted jet electrochemical machining, and waterjet-guided laser machining are reported. The experimental and theoretical studies of the technologies to improve the machining performance are discussed. Finally, the existing problems and the future research directions of the laser compound processing are put forward .

Thermal effects in laser assisted jet electrochemical machining

The purpose of the laser in laser assisted jet ECM (LAJECM) is to localise machining to specified areas so that precision and the productivity is improved. Temperature is a predominant determinant of this localisation effect and must be carefully monitored to avoid any heat affected zones or spark damage due to electrolyte boiling. This paper investigates the thermal effects in LAJECM on several alloys by temperature distribution modelling and experimental analysis. The laser influence on material micro removal has led to 25 μm deeper cavities with a reflective surface of roughness 20 nm R a, without any detectable heat affected zone.

Process Energy Analysis for Aluminium Alloy and Stainless Steel in Laser-Assisted Jet Electrochemical Machining

Laser-assisted jet electrochemical machining (LAJECM) is a hybrid process that combines a relatively low-power laser beam (typically 375 mW) with an electrolyte jet to facilitate metal removal. The main purpose of the laser is to enhance the localization effect of electrochemical dissolution from the workpiece, thus giving better precision and efficiency. The laser thermally activates the material surface where it impinges, thereby increasing the electrochemical current density in that localized zone. This paper reports recent investigations of LAJECM process energy distribution and explains the influence of laser assistance on dissolution removal rates using theoretical as well as experimental analysis. It was found that laser assistance increases energy in the LAJECM process by up to 45 per cent compared with jet electrochemical machining (JECM). The process energy has also been related to volumetric removal rate, and the specific energy required for machining with given variables has been calculated. It has been proved that LAJECM is more effective then JECM as the calculated specific energy was lower by up to 30 per cent.

Precision and efficiency of laser assisted jet electrochemical machining

Laser assisted jet electrochemical machining (LAJECM) is a hybrid process, that combines a laser beam with an electrolyte jet thereby giving a non-contact tool electrode that removes metal by electrochemical dissolution. The laser beam effectively improves the precision of LAJECM as it is able to direct the dissolution to specifically targeted areas. This prevents the machining from unwanted areas due to stray current. This parallel application of a laser beam with the electrolyte jet enables an improvement of machining accuracy, also productivity. LAJECM has shown that machining with laser assistance can effectively facilitate material removal of 20, 25, 33, and 54% for Hasteloy, titanium alloy, stainless steel and aluminium alloy, respectively. There is also a noticeable improvement in the shape accuracy and slight decrease in surface roughness of the holes and cavities produced due to more focused machining (the order of 20%). The measured reduction in taper is of the order of 38, 40, 41, 65% for aluminium alloy, stainless steel, Hasteloy and titanium alloy, respectively.

Modelling the aspects of precision and efficiency in laser-assisted jet electrochemical machining (LAJECM)

Laser-assisted jet electrochemical machining (LAJECM) is a hybrid process, which combines a relatively low-power laser beam and an electrolyte jet. Compared to single jet electrochemical machining, LAJECM yields better machining efficiency and precision, especially for small hole machining. The laser beam transfers additional heat on to a specific area of the workpiece area resulting in changed machining conditions. This localisation effect of machining is the key to improving accuracy and efficiency of the LAJECM. This paper presents also a mathematical modelling of the LAJECM process supported by experimental analysis.

Modelling and Experimental Investigation of Laser Assisted Jet Electrochemical Machining

Laser Assisted Jet Electrochemical Machining is a hybrid process which combines a relatively low power laser (375mW) with an electrolyte jet to facilitate metal removal. The main purpose of the laser is to enhance the localisation effect of electrochemical dissolution from the workpiece, thus giving better precision and machining efficiency. The laser thermally activates the material surface where it impinges thereby increasing the electrochemical current density in that localised zone. A theoretical model is used to explain the effects of localisation of electrochemical dissolution process. Experimental analysis using aluminium alloy and stainless steel has proved that laser assistance can yield up to 54% higher volumetric rate and up to 38% better accuracy than using electrolytic jet alone.