Essay: DESIGN AND DEVELOPMENT OF ELECTROCHEMICAL MACHINING SETUP WITH AUTOMATIC TOOL FEEDING MECHANISM

Abstract
Electrochemical Machining (ECM) is a non-traditional machining (NTM) process belonging to electrochemical category. ECM can be thought of a controlled anodic dissolution at atomic level of the work piece that is electrically conductive by a shaped tool due to flow of high current at relatively low potential difference through an electrolyte which is quite often water based neutral salt solution.
This project deals with the design and development of electrochemical machining setup. The different components required for setup of the machine are designed according to the available facilities. Also the different process parameters used for the machining are fixed. The work-piece material is taken as HCHCRD2 (High Carbon High Chromium Die Steel) to justify the process as this material cannot be machined with any other conventional machining source. The tool material is used as copper wire of 5mm diameter.
List of Figures
Figure 1.2 1 Working Of ECM [1] 1
Figure 1.2 2. Schematic View of ECM Machine [2] 2
Figure 1.7 1 Die Sinking [1] 4
Figure 1.7 2 3D Profiling [1] 4
Figure 1.7 3 Drilling [1] 5
Figure 1.7 4 Trepanning by ECM [1] 5
Figure 7.1 1 Proposed 3D Creo Model 17
Figure 7.1 2 ECM Machine with dimensions 17
Figure 8.1 1 Material Flow chart 18
Figure 8.2 1 Operation Process Chart 19
 
List of Tables
Table 5.7 1 Chemical Composition of HCHCRD2 14
Table 5.7 2 Mechanical Properties 14
Table 6.1 1 Composition and property of various components 16
 
TABLE OF CONTENT
Certificate………………………………………………………………………………………….i
Acknowledgement………………………………………………………………………………..ii
Abstract…………………………………………………………………………………………..iii
List of Figure……………………………………………………………………………………..iv
List of Tables………………………………………………………………………………………v
Table of Content………………………………………………………………………………….vi
1. Introduction 1
1.1 Overview 1
1.2 Introduction to ECM 1
1.3 Why ECM? 2
1.4 Key Features 3
1.5 Advantages 3
1.6 Disadvantages 3
1.7 Applications 4
2 Literature Review 6
2.1 Overview 6
2.2 Literature 6
2.2.1 Controlling of metal removal thickness in ECM process [3] 6
2.2.2 Investigation on Electrochemical Machining of EN31 Steel for Optimization of MRR and Surface Roughness using Artificial Bee Colony Algorithm [4] 6
2.2.3 Advancement in electrochemical micro-machining[2] 7
2.2.4 Generic aspects of tool design for electrochemical machining[5] 8
2.2.5 Design of Electrode Profile in Electrochemical Manufacturing Process [6] 8
2.2.6 Electrochemical machining of burn-resistant Ti40 alloy [7] 8
2.2.7 Effect of reinforcement particles on the abrasive assisted electrochemical machining of Aluminum-Boron carbide-Graphite composite [8] 9
3 Objective and Methodology 10
3.1 Overview 10
3.2 Objective 10
3.3 Methodology 10
4 Process Parameters 11
4.1 Overview 11
4.2 Parameters 11
5 Design and Selection of Various Components 12
5.1 Overview 12
5.2 Design of Lead Screw 12
5.2.1 Torque required by lead screw 12
5.3 Selection of nut 13
5.4 Selection of Stepper Motor 13
5.5 Selection of frame material 13
5.6 Power source details 14
5.7 Selection of the work piece 14
5.8 Work piece holding device 15
5.9 Selection of the container material 15
5.10 Selection of the tool 15
5.11 Selection of the X-Y position slide 15
5.12 Selection of the pump 15
6 Material removal Rate (MRR) 16
6.1 16
7 Proposed Creo Model of the Setup 17
7.1 17
8 Flow chart 18
8.1 Part list and Assembly chart 18
8.2 Operation Process Chart 19
9 Conclusion 20
9.1 Conclusion 20
9.2 Scope for future work 20
References 21
1. Introduction
1.1 Overview
This chapter describes Electrochemical Machining in brief stating its process, features, advantage, and limitations. Further it will give the idea of process parameters involved in experiments and how does it affects the Machining quality.
1.2 Introduction to ECM
The anodic dissolution of metals was already known in the previous century. But it was not until the 1960s that it came into use as a practical machining method. In non-traditional machining processes, electrochemical machining (ECM) has tremendous potential on account of versatility of its applications, and it is expected that it will be a promising, successful and commercially utilized machining process in the modern manufacturing industries. The ECM process was first patented by Gusseff in 1929. Significant advances during the 1950s and 1960s developed ECM into a major technology in the aircraft and aerospace industries for shaping, finishing, deburring and milling operations of large parts. All these processes of ECM now plays an important role in the manufacture of a variety of parts, ranging from machining complicated, shaped large metallic pieces to opening windows in silicon that are a few micrometers in diameter. ECM is an anodic dissolution process where work-piece and tool are respectively anode and cathode, which are separated by an electrolyte. When an electric current is passed through the electrolyte, the anode work-piece dissolves locally, so that the shape of the generated work-piece is approximately a negative mirror image of that of the tool.
Figure 1.2 1 Working Of ECM [1]
The electrolyte, which is generally a concentrated salt solution, is pumped at high velocities through the machining gap in order to remove the reaction products and to dissipate the heat generated. Machining performance in ECM is governed by the anodic behavior of the work piece material in a given electrolyte. In recent years, ECM has received much attention in the fabrication of micro parts. Fig shows a schematic view of an Electrochemical Machining (ECM) system set-up, which consists of pulsed DC power supply, machine controller, micro tool drive unit, mechanical machining unit, electrolyte flow system, etc
Figure 1.2 2.2.2 Schematic View of ECM Machine [2]
1.3 Why ECM?
ECM has seen a resurgence of industrial interest in the last decade due to its various advantages over other machining processes such as no tool wear, absence of stress/burr, high MRR, bright surface finish and the ability to machine complex shapes in materials regardless of their hardness. Recent changes in demand from society have forced the introduction of more and more micro-parts in various types of industrial products. For example, in the case of fuel injection nozzles for automobiles, several regulations arising from environmental problems have forced manufacturers to improve their design, making them smaller and more compact, with high accuracy.
1.4 Key Features
• Electrochemical Machining (ECM) is a non-traditional machining (NTM) process belonging to Electrochemical category
• It is the reverse process of Electroplating.
• This machining process is based on Michael Faraday’s classical laws of electrolysis.
• It basically requires two electrodes, an electrolyte, a gap and a source of DC power of sufficient capacity.
• Both internal and external geometries can be machined.
• Normally used for mass production and for hard materials that is difficult to machine using conventional processes.
1.5 Advantages
• Complete absence of any physical, structural, mechanical wear of tool electrode is ensured.
• Clamping is not required of the work piece as there are no cutting forces except for controlled motion.
• Can machine harder metals than the tool.
• No burrs and chips are obtained after machining.
• Precision machining.
• Relatively fast
• Hardness, toughness and magnetic qualities of the material do not change.
• Possibility to machine thin-walled contours
• Rough-machining, finish-machining and polishing in a single operation can be performed.
• Super alloys can be machined.
• Provides smooth surfaces.
• More sensitive and repeatable.
• Easily machines complex geometries.
• Surface finishes of up to Ra 0.05
1.6 Disadvantages
• In terms of cost, equipment is more expensive than standard machinery and equipment.
• Metal removal rate is slow
• Disposal of potentially harmful by-products
• Only electrically conductive materials can be machined
• High Specific Energy consumption
• The saline (or acidic) electrolyte poses the risk of corrosion to tool, work-piece and equipment.
• It produces a chemical sludge that needs to be disposed of.
1.7 Applications
ECM technique removes material by atomic level dissolution of the same by electrochemical action. Thus the material removal rate or machining is not dependent on the mechanical or physical properties of the work material. It only depends on the atomic weight and valency of the work material and the condition that it should be electrically conductive. Thus ECM can machine any electrically conductive work material irrespective of their hardness, strength or even thermal properties. Moreover as ECM leads to atomic level dissolution, the surface finish is excellent with almost stress free machined surface and without any thermal damage.
ECM is used for
• Die sinking
• Profiling and contouring
• Trepanning
• Grinding
• Drilling
• Micro-machining
Figure 1.7 1 Die Sinking [1]
Figure 1.7 2 3D Profiling [1]
Figure 1.7 3 Drilling [1]
Figure 1.7 4 Trepanning by ECM [1]
 
2 Literature Review
2.1 Overview
The chapter includes the various literature papers, journals, research work which has been done Electrochemical machining which we have studied. Based on the study we would further decide the design of the setup and process parameters of the process
2.2 Literature
2.2.1 Controlling of metal removal thickness in ECM process [3]
Electrochemical machining (ECM) offers the benefits of better accuracy and high surface finish of hard-machined components. A new method has been proposed to utilize a simultaneously moving and rotating electrode to remove a specific amount of material. One of the electrodes was provided with two simultaneous feeds, traverse speed and rotational speed. The electrolyte was pumped into the gap between the tool and the work-piece, through fine holes distributed along one of the electrode surface.
The accuracy and the productivity of the Electrochemical Machining process with a rotating electrode are affected not only by the average electrolyte flow rate, but also by the entire cross-section of the inter electrode gap. For hole finishing, experiments
have been carried out using fine perforated electrodes with the objective of achieving optimum machining performance in terms of high surface quality and minimal metal removal thickness.
Experimental results showed that in order to keep the machining process without sparking, it was necessary to provide an electrolyte flow rate more than 3 l/min. Also using electrodes with closely packed perforations caused tendency to sparking. As the applied voltage increases, the final metal removal thickness also increases. This has been attributed to the increase of current density as the applied voltage increases. It has been observed that as the initial gap value increases, metal removal thickness decreases.
2.2.2 Investigation on Electrochemical Machining of EN31 Steel for Optimization of MRR and Surface Roughness using Artificial Bee Colony Algorithm [4]
Experiments are done to make an empirical relationship between process parameters and responses using response surface methodology (RSM).
In this paper, artificial bee colony (ABC) algorithm is used to find out the optimal combinations of process parameters in Electrochemical Machining of EN 31 steel for maximum material removal rate (MRR) and minimum surface roughness (Ra).
Four process parameters viz. electrolyte concentration, voltage, feed rate and inter-electrode gap are considered in this study.
Then a multi-objective optimization is implemented to calculate the best solutions for maximum MRR and minimum surface roughness simultaneously using ABC.
Confirmation tests are carried out to check the validity of the study. Also results of confirmation tests matches with the predicted results.
Also, variations of responses with respect to process parameters are studied using 3D surface plots. Then the surface morphology is studied with the scanning electron microscopy (SEM).
2.2.3 Advancement in electrochemical micro-machining [2]
In this paper, a review is presented on current research, development and industrial practice in micro-Elecrochemical Machining. This paper highlights the influence of various predominant factors of EMM such as, design and development of micro tool, role of inter-electrode gap controlled material removal, machining accuracy, power supply and electrolyte, etc.
Basic principles and recent developments in power supply for EMM are also discussed.
In addition, the role of the electrolyte and electrolyte flow has been presented for a better understanding of the EMM process.
Tool shape plays a vital role in achieving accurate shape. The influence and methods of prediction of the inter-electrode gap are also discussed.
For continuous voltage, the efficiency decreases slowly when the current density is reduced, whereas with the pulsed voltage, the decrease is much more rapid.
Tool design mainly deals with the determination of tool shape, which will produce a work-piece with proper dimensions and accuracy. It is not yet successful for practical applications due to the complex gap configuration. The tool shape is a perfect negative mirror image of the work-piece to be produced; prediction of the tool shape is a formidable inverse boundary problem involving Laplace equations.
ECM electrolytes are classified into two categories: passivating electrolytes containing oxidizing anions, e.g. sodium nitrate, sodium chlorate, and non-passivating electrolytes containing relatively aggressive anions such as sodium chloride.
2.2.4 Generic aspects of tool design for electrochemical machining[5]
This paper concerns some of the generic aspects of tooling design for the electrochemical machining (ECM) process.
One of the main considerations for ECM tooling is the flow of the electrolyte solution. If the electrolyte is restricted as it exits from the flow slot, there is a very high risk of a spark occurring between the electrode and the workface. This is because there will be no solution to carry away the disassociated electrons from the work-piece and therefore no machining will occur. The machining gap will then get smaller and smaller until the tool and workface are so close together that sparks will occur between the two
When developing any electrode for a new operation, the electrode will invariably require adjustment. It is therefore advisable to manufacture the electrode from a soft material that can be easily altered; in this case Naval Brass was used and found to suit this purpose very well.
Peaks and valleys on the electrode face should be avoided as they cause electrolyte flow restrictions. If they must be included in the design, they should be as smooth as possible.
Also insulation should be considered. At any point where the electrode is likely to be opposite to the area of the component face that is not to be machined, insulation is needed to prevent undercutting. For development purposes, a non-conductive chemical metal can be used; this will help reduce the tooling cost. When the finished tooling is manufactured a hard non-conductive material should be used.
2.2.5 Design of Electrode Profile in Electrochemical Manufacturing Process [6]
Electrochemical manufacturing technologies based on Faraday law, including electrochemical machining (ECM) and electroforming plays an important role in the manufacturing industry.
According to theories of electric field and Electrochemistry, Laplace equation is used to describe electric potential distribution within gap domain.
The electroforming illustrated in Figure is an inverse process to ECM. The metal ions deposit on the pre shaped cathode mould when low voltage is applied across the gap between the anode and the cathode mould. The deposition process continues until the required thickness is reached. Then the deposited metal layer is mechanically separated from the cathode mould. The Inner or outer shape of the electroformed part is an exact negative mirror image of the cathode mould.
2.2.6 Electrochemical machining of burn-resistant Ti40 alloy [7]
This study investigates the feasibility of using electrochemical machining (ECM) to produce critical aero engine components from a new burn-resistant titanium alloy (Ti40), thereby reducing costs and improving efficiency relative to conventional mechanical machining. Through this, it is found that an aqueous mix of sodium chloride and potassium bromide provides the optimal electrolyte and that the surface quality of the Ti40 work-piece is improved by using a pulsed current of 1 kHz rather than a direct current. Furthermore, the quality of cavities produced by ECM and the overall material removal rate are determined to be dependent on a combination of operating voltage, electrolyte inlet pressure, cathode feeding rate and electrolyte concentration. By optimizing these parameters, a surface roughness of 0.371 lm has been achieved in conjunction with a specific removal rate of more than 3.1mm3/min.
2.2.7 Effect of reinforcement particles on the abrasive assisted electrochemical machining of Aluminum-Boron carbide-Graphite composite [8]
In this paper, attempts have been made to model and optimize process parameters in Abrasive assisted Electro-Chemical Machining (AECM) of Aluminium-5-15% boron carbide- 5-10% graphite composite using pre-shaped cylindrical copper tool electrodes. Sic abrasive particle size of 50μm is used along with NaCl electrolyte.
Optimization of process parameters is based on the statistical techniques with four independent input parameters such as voltage, current, reinforcement and feed rate were used to assess the AECM process performance in terms of material removal rate and surface roughness. The obtained results are compared with and without abrasive assisted ECM machining of Aluminium-B4C-Graphite composite.
The experiments were conducted on the specimens using METATECH ECM equipment. The tool was made of copper with circular cross section with central hole. The electrolyte was axially fed to the cutting zone through the central hole of the tool. NaCl is used as an electrolyte for both abrasive assisted and without abrasive ECM.
 
3 Objective and Methodology
3.1 Overview
This Chapter includes the objective of the project and the methodology to achieve it.
3.2 Objective
Design and development of electrochemical machining setup With Automatic Tool feeding Mechanism.
3.3 Methodology
 
4 Process Parameters
4.1 Overview
This chapter contains the working process parameters.
4.2 Parameters
• Power Supply Type :Direct current
Voltage 20V
Current: 50 A
• Electrolyte
Material: NaCl
Flow rate: 15-25 lpm
Dilution: 25% by Weight
• Working gap: 0.5 mm to 1.5 mm
• Feed rate: 0.5 mm/min to 1.5mm/min
• Electrode material: Tungsten
5 Design and Selection of Various Components
5.1 Overview
This chapter gives the design and selection of various mechanical components.
5.2 Design of Lead Screw
Load On Lead Screw: 20N
Nominal Diameter of lead screw (D): 10 mm
Pitch : 1mm
Pitch Diameter (D2) = D-0.5P
=9.5 mm
Basic Minor Diameter (D1) = D-P
= 9 mm
5.2.1 Torque required by lead screw
The Torque required by lead screw
F = Load on lead screw
= 20N
µ = Coefficient of Friction.
= 0.25
2α=29°
α = 14.5
dm = Mean Diameter of the lead screw= 10mm
l = lead
= 1mm
Torque required to raise the load is given by
= 0.298 kg-cm
Torque required to lower the load is given by
=0.2889 kg-cm
So the Lead screw with pitch 1mm and nominal diameter 10mm must be selected.
5.3 Selection of nut
The nut with nominal diameter 9.5mm is compatible with the lead screw
5.4 Selection of Stepper Motor
Step Angle required=1.8°
The torque required by the stepper motor ≥ Torque required for raising or lowering the load.
The stepper motor that fits the above and cost requirement is 4 kg-cm NEMA 17 Stepper Motor.
5.5 Selection of frame dimensions
• The process of designing the frame was started from the dimensions of X-Y slide, from which the dimensions of base were obtained.
• After that the dimensions of container were obtained in which the work-piece and its holding device are to be kept.
• From all these components the total height from the base was obtained.
• Then the height of tool holder was obtained with respect to the work-piece and tool.
• Then height of tie rod was obtained from the base.
• And so the height of entire frame was obtained from base.
• The available sections for frame were box section, angle section, C section, I section, hollow circular section.
• To decrease overall weight and easy availability of angle section frame at ADIT workshop angle section was decided.
• For beam containing the lead screw and stepper motor the rectangular-section is used.
5.6 Power source details
The power source is 3 Phase DC Rectifier.
Maximum available current= 400A.
Maximum Voltage = 80 V.
5.7 Selection of the work piece
The material of the work piece should be such that it justifies the use of ECM as a working process. So HCHCRD2 (High carbon high Chromium Die Steel) is used as the material of the work piece because it has high hardness and cannot be easily machined by conventional methods.
• Chemical Composition.
Element Content(%)
C 1.5
Mn 0.25
Si 0.15
S 0.03
Cr 11.13
Mo 0.8
P 0.03
Fe 86.24
Table 5.7 1 Chemical Composition of HCHCRD2
• Mechanical Properties.
Property Value
Density (lb./cu.in.) 0.284
Specific Gravity 7.9
Specific heat(Btu/lb./Deg F-[32-212 Deg F]) 0.107
Melting point (Deg F) 2740
Thermal conductivity 360
Modulus of elasticity tension 30
Hardness 58 HRC
Table 5.7 2 Mechanical Properties
The size of the work piece to be used is 50mm x 50mm x 10mm.
5.8 Work piece holding device
The work holding device must be a non-conductor of the electricity. So it is made of acrylic. It can accommodate a work piece with maximum size of 50mm x 100mm x20mm.
5.9 Selection of the container material
The container will act as the machining chamber, so its material must be non-conductor of electricity. Also the container should contain required amount of electrolyte in the machining chamber.
Thus container is made of the acrylic sheet of thickness 10mm. The dimension of the machining chamber is 250mm x 250mm x 100mm.
5.10 Selection of the tool
There is no direct contact between work piece and the tool. Tool can machine any conductive work piece irrespective of its hardness. The main use of the tool material is to transfer the electricity.
So here Copper rod of diameter 5mm is used as tool.
5.11 Selection of the X-Y position slide
The X-Y position slide is selected such that it gives the maximum travel 15 cm in both the directions. An acrylic container of base area 250mmx250mm is to be mounted on it.
5.12 Selection of the pump
A 12 Watt Pump with discharge 80-120 liters/hour is selected for pumping the electrolyte.
 
6 Material removal Rate (MRR)
6.1
The formula for MRR is given by: –
F= Faraday’s constant.
Δa =Total volume of material dissolved.
t =Time of machining.
ρ =Density of work piece.
αi =Proportion of ith component in work piece.
Ï…i = Valency of the ith component
Ai = Atomic weight of ith component in work piece.
I = Current in Ampere.
The component used here is HCHCRD2
Sr no Name of Component Percentage of Composition(%) Valency Atomic Weight(gm)
1 C 1.5 4 12
2 Mn 0.25 2 54
3 Si 0.15 4 28
4 S 0.03 2 32
5 Cr 11.13 2 51
6 Mo 0.8 6 95
7 P 0.03 3 30
8 Fe 86.24 3 55
Table 6.1 1 Composition and property of various components
Material Removal Rate obtained for 50A from above formula is 6694 mm3/sec.
7 Proposed Creo Model of the Setup
7.1
Figure 7.1 1 Proposed 3D Creo Model
Figure 7.1 2 ECM Machine with dimensions
8 Flow chart
8.1 Part list and Assembly chart
PART LIST ASSEMBLY 1 ASSEMBLY 2 FINAL ASSEMBLY
WORK-PIECE WORK-PIECE MACHINING CHAMBER WITH WORK-PIECE ELECTROCHEMICAL MACHINING SETUP FINAL ASSEMBLY
WORK-PIECE HOLDING DEVICE
NOZZLE MACHINING CHAMBER
ACRYLIC CONTAINER
TOOL TOOL MAIN FRAME
TOOL HOLDING DEVICE
TIE RODS & VERTICAL COLUMN FRAME
X-Y SLIDE
STEPPER MOTOR TOOL MOTION MECHANISM
ARDUINO
DC POWER SOURCE POWER SOURCE
CLAMPING DEVICE FOR WORK-PIECE
CLAMPING DEVICE FOR ELECTRODE
RESERVOIR FOR ELECTROLYTE ELECTROLYTE ASSEMBLY
PUMP
ELECTROLYTE
PIPING SYSTEM
FILTER
SETTLING TANK
RETURN SYSTEM FROM CHAMBER TO RESERVOIR
Figure 8.1 1 Part list and Assmebly chart
8.2 Operation Process Chart
2. Conclusion
8.3 Conclusion
• As per the objective the design parameters and process parameters for the setup to be prepared are obtained.
• The complete part-list of components required for setup is obtained.
• The dimensions of the components to be included in setup are obtained.
• The work-piece material is taken as HCHCRD2 (High Carbon High Chromium Die Steel) to justify the process as this material cannot be machined with any other conventional machining source.
• The tool material is used as copper wire of 5mm diameter.
• Also the process parameters which are to be used while machining are fixed according to the available facilities.
• The Operation Flow Chart is obtained for sequence of the operations to be performed for preparation of setup.
• The material flow chart according to which the assemblies are required to be prepared is obtained.
• The ranges for the dimensions of work-piece and motion transfer are obtained.
• The design of entire assembly for the setup is completed.
8.4 Scope for future work
• Fabricate and develop the Electrochemical machining setup with automatic feed mechanism using the designed design parameters as well as process parameters.
• Check the feasibility and working of the setup with respect to different parameters.
• Modify the setup if required.
References
[1]. Module 9 Non-conventional Machining Version 2 ME, IIT Kharagpur.
[2]. Advancement in electrochemical micro-Machining by B Bhattacharya,J Munda, M Malapati, Department of Production engineering , Jadavpur university, Kolkata, 700032 India, International Journal of Machine Tools & Manufacture 44 (2004) 1577—1589.
[3]. Controlling of metal removal thickness in ECM Process, M.S.Hewidy, Department of Production Engineering and Machine Design, Faculty of Engineering, Menoufia University, Shebin El-Kom Egypt, Received 18th April 2001, Received in revised form 6th March 2002Acepted 6th August 2003, Journal of material Procressing Technology 160(2005) 348-535
[4]. Investigation on Electrochemical Machining of EN31 Steel for Optimization of MRR and Surface Roughness using Artificial Bee Colony Algorithm, Milan Kumar Dasa, Kaushik Kumarb, Tapan Kr. Barmana and Prasanta Sahooa Procedia Engineering 97 ( 2014 ) 1587 — 1596
[5]. Generic aspects of tool design for electrochemical machining. J.A. Westley a, J. Atkinson a,∗ A. Duffield b. Manufacturing Division, Department of Mechanical Engineering, University of Manchester Institute of Science and Technology, P.O. Box 88, Sackville Street, Manchester M60 1QD, UK b Hampson Aerospace, Pegasus House, Bromford Gate, Bromford Lane, Birmingham B24 8DW, UK. Journal of Materials Processing Technology 149 (2004) 384—392
[6]. Design of Electrode Proflle In Electrochemical Manufacturing Process. D.Zhu’(2),K.Wang’, J. M. Yang’. Research Center for Nontraditional Machining. College of Mechanical and Electrical Engineering. Nanjing University of Aeronautics and Astronautics, China
[7]. Electrochemical machining of burn-resistant Ti40 alloy. Xu Zhengyang *, Liu Jia, Zhu Dong, Qu Ningsong, Wu Xiaolong, Chen Xuezhen. College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. Chinese Journal of Aeronautics, (2015), 28(4): 1263—1272
[8]. Effect of reinforcement particles on the abrasive assisted electrochemical machining of Aluminium —Boron carbide Graphite composite. M.Sankara, A.Gnanavelbabub, K.Rajkumarc. aAssistant Professor, Department of Mechanical Engineering, Surya Group of Institutions, Villupuram- 605652, Tamil Nadu, India. Associate Professor, Department of Industrial Engineering, CEG Campus, Anna University, Chennai-600025, Tamil Nadu, India. Associate Professor, Department of Mechanical Engineering, SSN College of Engineering, Chennai-603110, Tamil Nadu, India. Procedia Engineering 97 ( 2014 ) 381 — 389