Electrochemical Machining—Prediction and Correlation of Process Variables

1966 ◽  
Vol 88 (4) ◽  
pp. 455-461 ◽  
Author(s):  
J. Hopenfeld ◽  
R. R. Cole
Keyword(s):  
Flow Rate ◽  
Metal Removal ◽  
Electrochemical Machining ◽  
Electrolytic Cell ◽  
Process Variables ◽  
Electrode Gap ◽  
Electrolyte Flow ◽  
Normal Current Density ◽  
Anode Dissolution ◽  
Bubble Layer

The relationship between total current, applied potential, electrolyte flow rate, electrolyte conductivity, and electrode gap in electrochemical machining was investigated experimentally and analytically. An electrolytic cell was designed permitting the electrode gap to be observed and photographed. A 0.25 × 0.375-in. rectangular 1100F aluminum anode was used. Electrode gap varied between 0.013 and 0.033 in. The electrolyte was potassium chloride in concentrations from 0.67 normal to 1.7 normal. Current density range was 40–450 amp/in. and electrolyte flow rate was 0.22 to 0.98 gal/min. The photographs taken of the electrode gap during operation clearly show development of a hydrogen bubble layer next to the cathode. Based upon a mathematical model incorporating the bubble layer, an equation in a nondimensional form has been derived describing the functional relationship between process variables. This equation correlates the experimental data within plus or minus 15 percent. An equation which predicts the local current distribution, and hence anode dissolution rate, along the electrode gap in the direction of electrolyte flow is also presented. Based on the theoretical analysis, optimum operation in electrochemical machining from the standpoint of uniformity of metal removal is discussed.

Cathode Design of Aero-Engine Blades in Electrochemical Machining Based on Characteristics of Gap Distribution

2009 ◽  
Vol 69-70 ◽  
pp. 248-252 ◽  
Author(s):  
Ji Hua ◽  
Zhi Yong Li
Keyword(s):  
High Surface ◽  
Electrochemical Machining ◽  
Dimensional Accuracy ◽  
Machining Accuracy ◽  
Electrode Gap ◽  
Electrolyte Flow ◽  
High Surface Quality ◽  
Cathode Design ◽  
Aero Engine ◽  
Electric Filed

Cathode design is a difficult problem must be faced and solved in ECM. We develop a new numerical approach for cathode design by employing a finite element method and this approach has been applied in the cathode design of aero-engine blades in ECM. The mathematic models of the electric filed and electrolyte flow filed distribution in EMC process are described primarily. Then the realization procedure of this approach is presented，in which the effects of electric filed and electrolyte flow filed distribution within the inter-electrode gap domain are concentrated. In order to verify the machining accuracy of the designed cathodes, the experiments are conducted using an industrial scale electrochemical machining system. The experimental results demonstrate that the machined blade have high surface quality and dimensional accuracy which proves the proposed approach for cathode design of aero-engine blades in ECM is applicable and valuable.

Removal of Defective Layer after Electrical Discharge Machining

2019 ◽  
Vol 973 ◽  
pp. 157-160
Author(s):  
Stanislav A. Mozgov ◽  
Yuriy A. Morgunov ◽  
Boris P. Saushkin
Keyword(s):  
Electrical Discharge ◽  
Metal Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Electrochemical Machining ◽  
Work Piece ◽  
Machining Parameters ◽  
Electrode Gap ◽  
Machining Time ◽  
Defective Layer

This study investigates the possibility of electrochemical removal of the defective layer formed on the surface of the product after its electrical discharge machining. A set of experiments was conducted in different electrolytes based on aqueous and aqueous-organic solvents. The experiments were to trace the influence of such settings of electrochemical machining as current density, electrolyte pumping speed, electrolyte temperature, and an electrode gap upon both the dynamics of metal removal and surface quality. Morphology of the obtained surface was examined by an Olympus BX-51Microscope. The dynamics of removing material (stock) from the work piece was inspected. Appropriate adjustments were made to the machining parameters during the machining of 65G steels, and a preferred composition was selected for the working medium. A sufficient design for production tools was proposed. Pitting corrosion was discovered on the surface of the samples in all studied modes of electrolysis. It was observed that switching from aqueous electrolyte to aqueous-organic electrolyte gave lower material removal rate and longer machining time accordingly. At the same time, a reduction in surface roughness was visualized, together with smaller pits and lower density of their distribution. The obtained results may be applied in operation design for electrochemical machining of steels with relatively high carbon contents.

Development of a Prototype of Electrochemical Machining

2011 ◽  
Vol 223 ◽  
pp. 940-949 ◽  
Author(s):  
Silva Neto ◽  
João Cirilo
Keyword(s):  
Power Supply ◽  
Material Removal ◽  
Metal Removal ◽  
State Of The Art ◽  
Removal Rate ◽  
Three Dimensional ◽  
Electrochemical Machining ◽  
Electrolytic Cell ◽  
Parameter Control ◽  
Purification System

Electrochemical machining (ECM) is the controlled removal of material by anodic dissolution in an electrolytic cell in which the workpiece is the anode and the tool is the cathode. The ECM presents the advantages: three-dimensional surfaces with complicated profiles can be easily machined in a single operation, irrespective of the hardness and strength of the material. ECM offers a higher rate of metal removal as compared to traditional and nontraditional methods, especially when high machining currents are employed. There is no wear of the tool, which permits repeatable production. This work shows a study of development of a prototype of electrochemical machining (ECM) developed at the Federal University of Uberlândia Minas Gerais-Brazil. A state-of-the-art ECM system is the art of assemblage of facilities including a proper ECM machine, a power supply, a process parameter control system, and an electrolyte preparation, feed and purification system. With the prototype developed, the material removal rate (MRR) was studied. The MRR was influenced by tool feed rate and type of electrolyte.

The influence of zinc electrode substrate, electrolyte flow rate and current density on zinc-nickel flow cell performance

2021 ◽  
Vol 373 ◽  
pp. 137890
Author(s):  
David P. Trudgeon ◽  
Adeline Loh ◽  
Habib Ullah ◽  
Xiaohong Li ◽  
Vladimir Yufit ◽  
...  
Keyword(s):  
Flow Rate ◽  
Current Density ◽  
Flow Cell ◽  
Cell Performance ◽  
Zinc Electrode ◽  
Electrolyte Flow ◽  
Zinc Nickel

scholarly journals Research on Stagger Coupling Mode of Pulse Duration and Tool Vibration in Electrochemical Machining

2018 ◽  
Vol 8 (8) ◽  
pp. 1296 ◽  
Author(s):  
Xiaochen Jiang ◽  
Jia Liu ◽  
Di Zhu ◽  
Mingming Wang ◽  
Ningsong Qu
Keyword(s):  
Pulse Duration ◽  
Feed Rate ◽  
Electrochemical Machining ◽  
Machining Accuracy ◽  
Electrode Gap ◽  
Tool Vibration ◽  
Coupling Mode ◽  
Machining Localization ◽  
Electrolysis Products ◽  
Gas Void Fraction

Tuning the coupling of pulse duration and tool vibration in electrochemical machining (PVECM) is an effective method to improve machining accuracy and surface quality. In general, the pulse is set at the same frequency as the tool vibration, and a symmetrical distribution is attained at the minimum inter-electrode gap. To analyse the characteristics of the electrolyte fluid flow and of the electrolysis products in the oscillating inter-electrode gap, a dynamic simulation of the PVECM process was carried out. The simulation results indicated that the electrolyte pressure and gas void fraction when the pulse arrived as the inter-electrode gap was narrowing clearly differed from those when the inter-electrode gap was expanding. Therefore, in addition to the traditional symmetry coupling mode, two other coupling modes called the pre-position and the post-position coupling modes are proposed which use a pulse either just before or just after the minimum inter-electrode gap. Comparative experiments involving the feed rate and machining localization were carried out to evaluate the influence of the three coupling modes. In addition, current waveforms were recorded to analyse the differences between the three coupling modes. The results revealed that the highest feed rate and the best machining localization were achieved by using the pre-position coupling mode.

Effect of Process Variables on Efficiency and Particle Growth of Spilanthes oleracea Seeds Coating

2010 ◽  
Vol 660-661 ◽  
pp. 419-425 ◽  
Author(s):  
C.M.L. Costa ◽  
L.J.G. Faria ◽  
Cristina dos Santos Rocha Sandra
Keyword(s):  
Fluidized Bed ◽  
Flow Rate ◽  
Particle Growth ◽  
Process Variables ◽  
Relative Growth ◽  
Coating Efficiency ◽  
Fluidized Bed Coating ◽  
Common Technique ◽  
Coating Suspension ◽  
Granule Growth

The coating of vegetable seeds is a very common technique, mainly for the species which have small seeds. One of its functions is to increase the seed size to direct sowing. In the present study the coating of Spilanthes oleracea L. seeds with a polymeric suspension in fluidized bed was analyzed. The effects of process variables on the coating efficiency of top-spray fluidized bed coating were evaluated. The independent variables studied were the flow rate of coating suspension and the air mass flow. The quantification for the entrance variables influence on the coating efficiency and granule growth, as well as the identification of optimal conditions were made by means of an experiment factorial design technique. Polynomial models for the responses: efficiency and relative growth of the particles were deduced. The highest coating efficiency was achieved at a high flow rate of coating suspension.

Parameters Research of Precise Straightening Process in Roll Straightener

2015 ◽  
Vol 1095 ◽  
pp. 800-803
Author(s):  
Qiang Chen ◽  
Shan Li ◽  
Ying Luo ◽  
Wen Long Lu
Keyword(s):  
Computer Simulation ◽  
Electrochemical Machining ◽  
Electrolytic Cell ◽  
Copper Cathode ◽  
Optimization Analysis ◽  
High Quality ◽  
Plate Method ◽  
Plate Spacing ◽  
Urgent Task ◽  
Computer Optimization

Refined copper to obtain high quality can use the electrolytic method; the copper cathode plate is applied to the electrochemical machining. In order to make copper cathode plate has high flatness, assuring electrolytic cell cathode and anode plate spacing, so that the purity of copper electrolysis precipitation is higher, so change the straightening plate method has become the urgent task of the enterprise. Through the computer simulation, the ANSYS/LS-DYNA computer optimization, analysis precise straightening device parameters, in ensuring the copper starting sheet straightening can meet basic factories requirements, improve the machining precise straightening machine and copper starting sheet straightening efficiency.

LTCC 3D FLOW FOCALIZATION DEVICE FOR LIQUID-LIQUID PARTIAL SOLVENT EXTRACTION

2016 ◽  
Vol 2016 (CICMT) ◽  
pp. 000111-000117
Author(s):  
Houari Cobas Gomez ◽  
Jéssica Gonçalves da Silva ◽  
Jocasta Mileski Machado ◽  
Bianca Oliveira Agio ◽  
Francisco Jorge Soares de Oliveira ◽  
...  
Keyword(s):  
Solvent Extraction ◽  
Aqueous Phase ◽  
Microfluidic Device ◽  
Flow Rate ◽  
Extraction Efficiency ◽  
Channel Length ◽  
Main Channel ◽  
Process Variables ◽  
3D Flow ◽  
Acetone Concentration

Abstract The present work shows a ceramics microfluidic device for partial solvent extraction scheme. The technology used for device fabrication was Low Temperature Cofired Ceramics (LTCC) which allows us for complex and chemical resistant 3D microfluidic devices. The proposed system aims to partially extract the solvent present in a mixture containing aqueous and organic phases. This scheme uses a 3D flow focalization in order to improve the solvent diffusion into the external aqueous phase. The device is composed by three different parts, the input channels distribution, the main channel and the output channels distribution. The designed input channels distribution ensures a centered 3D focalized solvent stream along the main channel. The focalized solvent mixes with the surrounding water thanks to diffusion. Projected output channels take the central fluid out separately from the surrounding. Thus the device has two different outputs, one for the focalized fluid and another one for the waste fluid, which is the aqueous phase plus solvent. For a device concept proof, acetone and water were used as organic and aqueous phases, respectively. COMSOL Multiphysics was used for device microfluidics and chemical transport simulation. The extraction efficiency was the variable used as indicator for device performance validation. The flow rate ratio between phases, total flow rate, main channel length and focalized stream channel output hydraulic diameter (ODH) were used as process variables for simulation purposes. A factorial experimental planning was used in order to analyze the extraction efficiency taking into account process variables effects. From simulation results it was determined main channel length and ODH as the variables with stronger effect on extraction efficiency. Obtained simulated efficiencies were as high as 80.6%. Considering previous results observations a microfluidic device was fabricated with a main channel length of 21,4 mm and ODH of 214,63 μm. Gas chromatography was used to measured acetone concentration in outputs samples and from here the extraction efficiency. Experimental results were in agreement with simulation, returning extraction efficiencies in the order of 80.8% ± 2.2%.

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