scholarly journals Improvement of the Machining Performance of the TW-ECDM Process Using Magnetohydrodynamics (MHD) on Quartz Material

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2377
Author(s):  
Ankit D. Oza ◽  
Abhishek Kumar ◽  
Vishvesh Badheka ◽  
Amit Arora ◽  
Manoj Kumar ◽  
...  

Many microslits are typically manufactured on quartz substrates and are used to improve their industrial performance. The fabrication of microslits on quartz is difficult and expensive to achieve using recent traditional machining processes due to its hardness, electrically insulating nature, and brittleness. The key objective of the current study was to demonstrate the fabrication of microslits on quartz material through a magnetohydrodynamics (MHD)-assisted traveling wire-electrochemical discharge micromachining process. Hydrogen gas bubbles were concentrated around the entire wire surface during electrolysis. This led to a less active dynamic region of the wire electrode, which decreased the adequacy of the electrolysis process and the machining effectiveness. The test results affirmed that the MHD convection approach evacuated the gas bubbles more rapidly and improved the void fraction in the gas bubble scattering layer. Furthermore, the improvements in the material removal rate and length of the cut were 85.28% and 48.86%, respectively, and the surface roughness was reduced by 30.39% using the MHD approach. A crossover methodology with a Taguchi design and ANOVA was utilized to study the machining performance. This exploratory investigation gives an unused strategy that shows a few advantages over the traditional TW-ECDM process.

Author(s):  
Alakesh Manna ◽  
Amandeep Kundal

Advanced ceramic materials are gradually becoming very important for their superior properties such as high hardness, wear resistance, chemical resistance, and high strength to weight ratio. But machining of advanced ceramic like Al2O3-ceramics is very difficult by any well known and common machining processes. Normally, cleavages and triangular fractures generate when machining of these materials is done by traditional machining methods. It is essential to develop an efficient and accurate machining method for processing advanced ceramic materials. For effective machining of Al2O3-ceramics, a traveling wire electrochemical spark machining (TW-ECSM) setup has been developed. The developed TW-ECSM setup has been utilized to machine Al2O3 ceramic materials and subsequently test results are utilized to analyze the machining performance characteristic. Different SEM photographs show the actual condition of the micro machined surfaces. The practical research analysis and test results on the machining of Al2O3 ceramics by developed TWECSM setup will provide a new guideline to the researchers and manufacturing engineers.


Author(s):  
Alakesh Manna ◽  
Amandeep Kundal

Advanced ceramic materials are gradually becoming very important for their superior properties such as high hardness, wear resistance, chemical resistance, and high strength to weight ratio. But machining of advanced ceramic like Al2O3-ceramics is very difficult by any well known and common machining processes. Normally, cleavages and triangular fractures generate when machining of these materials is done by traditional machining methods. It is essential to develop an efficient and accurate machining method for processing advanced ceramic materials. For effective machining of Al2O3-ceramics, a traveling wire electrochemical spark machining (TW-ECSM) setup has been developed. The developed TW-ECSM setup has been utilized to machine Al2O3 ceramic materials and subsequently test results are utilized to analyze the machining performance characteristic. Different SEM photographs show the actual condition of the micro machined surfaces. The practical research analysis and test results on the machining of Al2O3 ceramics by developed TWECSM setup will provide a new guideline to the researchers and manufacturing engineers.


2019 ◽  
Vol 8 (2) ◽  
pp. 6508-6515

Today, the appropriate use of precision machining to produce three dimensional miniaturized structures or micro devices is another challenging task. Thus, presently miniaturization has emerged as a thrust area of research. The micro components are normally provided with micro channels which are created by using micro tools with the help of nonconventional machining processes. The aim of this paper is to examine machining performance of making micro channels in pure-Ti using ultrasonic machining. The effect of abrasive type, power rating, slurry concentration, feed rate and abrasive size has been investigated on responses namely metal removal rate (MRR) and surface roughness (SR). Taguchi based L18 (mixed level) orthogonal array is selected for the planning of experiments. Finally, the validation experiments have been performed at suggested optimal settings for result reproducibility.


Author(s):  
Goutam Kumar Bose ◽  
Pritam Pain

In modern-day manufacturing Electric Discharge Machining (EDM) process has successfully placed itself in the domain of precision machining and generating complex geometries where secondary machining processes are eliminated. In this research paper, a die sinking EDM is applied to machine mild steel in order to measure the different multi-objective results like Material Removal Rate (MRR) and Over Cut (OC). This contradictory objective is accomplished by using the control parameters like a pulse on time, duty factor, gap current and spark gap employing copper tool with lateral flushing. Here the individual objective function of the responses is created through regression analysis. Primarily the contradictory objectives are optimized by employing Taguchi Methodology, then Regression analysis is done on the test results. Additionally, the experimental results are optimized using Response Surface Methodology (RSM). It is followed by a multi-objective optimization through Overlaid contour plots and Desirability functions to ascertain the best parametric combination amongst the set of feasible alternatives.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Venkata N. Raju Jampana ◽  
P. S. V. Ramana Rao ◽  
A. Sampathkumar

Electric discharge machining (EDM) process is one of the earliest and most extensively used unconventional machining processes. It is a noncontact machining process that uses a series of electric discharges to remove material from an electrically conductive workpiece. This article is aimed to do a comprehensive experimental and thermal investigation of the EDM, which can predict the machining characteristic and then optimize the output parameters with a newly integrated neural network-based methodology for modelling and optimal selection of process variables involved in powder mixed EDM (PMEDM) process. To compare and investigate the effects caused by powder of differently thermo physical properties on the EDM process performance with each other as well as the pure case, a series of experiments were conducted on a specially designed experimental setup developed in the laboratory. Peak current, pulse period, and source voltage are selected as the independent input parameters to evaluate the process performance in terms of material removal rate (MRR) and surface roughness (Ra). In addition, finite element method (FEM) is utilized for thermal analysis on EDM of stainless-steel 630 (SS630) grade. Further, back propagated neural network (BPNN) with feed forward architecture with analysis of variance (ANOVA) is used to find the best fit and approximate solutions to optimization and search problems. Finally, confirmation test results of experimental MRR are compared using the values of MRR obtained using FEM and ANN. Similarly, the test results of experimental Ra also compared with obtained Ra using ANN.


Author(s):  
Sundar Marimuthu ◽  
Bethan Smith

This manuscript discusses the experimental results on 300 W picosecond laser machining of aerospace-grade nickel superalloy. The effect of the laser’s energetic and beam scanning parameters on the machining performance has been studied in detail. The machining performance has been investigated in terms of surface roughness, sub-surface thermal damage, and material removal rate. At optimal process conditions, a picosecond laser with an average power output of 300 W can be used to achieve a material removal rate (MRR) of ∼140 mm3/min, with thermal damage less than 20 µm. Shorter laser pulse widths increase the material removal rate and reduce the resultant surface roughness. High scanning speeds improve the picosecond laser machining performance. Edge wall taper of ∼10° was observed over all the picosecond laser machined slots. The investigation demonstrates that high-power picosecond lasers can be used for the macro-machining of industrial components at an acceptable speed and quality.


2021 ◽  
Vol 64 (4) ◽  
pp. 1381-1389
Author(s):  
Fengwei Gu ◽  
Meng Yang ◽  
Zhichao Hu ◽  
Yanhua Zhang ◽  
Chong Zhang ◽  
...  

HighlightsAn efficient method for separating peanut seedlings and residual film harvested from film-mulched peanut was proposed, and the mechanism was optimized.The relationships between the suspension velocity and moisture content of different shredded materials were studied.Four-factor, three-level Box-Behnken experiments were carried out and analyzed, and the optimal parameter combination was determined.A validation test was carried out to verify the rationality and accuracy of the optimized regression model.Abstract. To address the problems of lower residual film removal and higher material loss in the forage utilization of peanut seedlings wrapped in residual film, this study explored the relationships between the suspension velocity and moisture content of different shredded materials derived from peanut seedlings and conducted performance tests and parameter optimization for a machine that uses peanut seedlings as forage material. Four-factor, three-level Box-Behnken experiments were designed using the rotational speeds of the shredding shaft, upper fans, and lower fans and the frequency of the vibrating sieve as test factors, and using the residual film removal rate and material loss rate as response values. The test results indicated that the suspension velocity of the shredded materials showed a quadratic relationship with moisture content. The performance tests showed that the significance sequence of the test factors for the residual film removal rate was: rotational speed of the lower fans, rotational speed of the upper fans, rotational speed of the shredding shaft, and frequency of the vibrating sieve. The significance sequence for the material loss rate was: rotational speed of the lower fans, rotational speed of the shredding shaft, frequency of the vibrating sieve, and rotational speed of the upper fans. The parameter optimization and validation test showed that the residual film removal rate was 92.71% and the material loss rate was 8.19% when the rotational speeds of the shredding shaft, upper fans, and lower fans were 1650, 770, and 665 rpm, respectively, and the frequency of the vibrating sieve was 4 Hz. The relative errors between the validation test results and the predicted values from the regression models were less than 3%, which suggests that the regression models are reliable. This study provides a reference for the forage utilization of peanut seedlings harvested from film-mulched peanut and provides a reference for determining the optimal working parameters of forage processing machines. Keywords: Agricultural machinery, Box-Behnken experiment, Optimization, Peanut film-seedling separation, Suspension velocity.


Author(s):  
Sagil James ◽  
Sharadkumar Kakadiya

Shape Memory Alloys are smart materials that tend to remember and return to its original shape when subjected to deformation. These materials find numerous applications in robotics, automotive and biomedical industries. Micromachining of SMAs is often a considerable challenge using conventional machining processes. Micro-Electrical Discharge Machining is a combination of thermal and electrical processes, which can machine any electrically conductive material at micron scale independent of its hardness. It employs dielectric medium such as hydrocarbon oils, deionized water, and kerosene. Using liquid dielectrics has adverse effects on the machined surface causing cracking, white layer deposition, and irregular surface finish. These limitations can be minimized by using a dry dielectric medium such as air or nitrogen gas. This research involves the experimental study of micromachining of Shape Memory Alloys using dry Micro-Electrical Discharge Machining process. The study considers the effect of critical process parameters including discharge voltage and discharge current on the material removal rate and the tool wear rate. A comparison study is performed between the Micro-Electrical Discharge Machining process with using the liquid as well as air as the dielectric medium. In this study, microcavities are successfully machined on shape memory alloys using dry Micro-Electrical Discharge Machining process. The study found that the dry Micro-Electrical Discharge Machining produces a comparatively better surface finish, has lower tool wear and lesser material removal rate compared to the process using the liquid as the dielectric medium. The results of this research could extend the industrial applications of Micro Electrical Discharge Machining processes.


Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 41 ◽  
Author(s):  
Hao Zhu ◽  
Zhaoyang Zhang ◽  
Kun Xu ◽  
Jinlei Xu ◽  
Shuaijie Zhu ◽  
...  

The fabrication of micro-holes in silicon substrates that have a proper taper, higher depth-to-diameter ratio, and better surface quality has been attracting intense interest for a long time due to its importance in the semiconductor and MEMS (Micro-Electro-Mechanical System) industry. In this paper, an experimental investigation of the machining performance of the direct and chemical-assisted picosecond laser trepanning of single crystalline silicon is conducted, with a view to assess the two machining methods. The relevant parameters affecting the trepanning process are considered, employing the orthogonal experimental design scheme. It is found that the direct laser trepanning results are associated with evident thermal defects, while the chemical-assisted method is capable of machining micro-holes with negligible thermal damage. Range analysis is then carried out, and the effects of the processing parameters on the hole characteristics are amply discussed to obtain the recommended parameters. Finally, the material removal mechanisms that are involved in the two machining methods are adequately analyzed. For the chemical-assisted trepanning case, the enhanced material removal rate may be attributed to the serious mechanical effects caused by the liquid-confined plasma and cavitation bubbles, and the chemical etching effect provided by NaOH solution.


2014 ◽  
Vol 926-930 ◽  
pp. 4361-4364
Author(s):  
Xiao Qiao Song

When straw pulp papermaking wastewater was treated by the process of coagu-flocculation and nuclear-flocculation, there were still high CODCr. UV254 can reflect organic pollutants and organic pollutants of unsaturated aromatic ring, carbon-carbon double bond. With the decrease of molecular weight of organic pollutants, absorption of ultraviolet light will decrease. Indirectly, it reflectd that the combination process had a good removal effect on high molecular aromatic hydrocarbons difficult to be biodegraded. Meanwhile it can improve the the biodegradability. It used the activated sludge process as subsequent process of coagulation and-flocculation process. The test results showed that the removal rate of CODCr was 24.1%, CODCr was the 88.1mg/L. It reached effluent standard.


Sign in / Sign up

Export Citation Format

Share Document