Influence of Workpiece Shape on MRR and EWR in EDM of Steel

2014 ◽  
Vol 903 ◽  
pp. 51-55 ◽  
Author(s):  
Alexis Mouangue Nanimina ◽  
Ahmad Majdi Abdul Rani ◽  
Mohd Amri Lajis ◽  
Turnad Lenggo Ginta ◽  
T.V.V.L.N. Rao

Shape of workpiece, electrode orientation and flushing system play important role in electrical discharge machining (EDM) process. Low material removal rate and relatively high electrode wear ratio are some of the disadvantages of EDM process. This can be due to the flushing modes. Workpiece shape has a significant effect in effectiveness of dielectric flushing flow and orientation during EDM process. This research work is conducted to analyze the influence of various workpiece shapes. Square cavity, L shape, flat shape and U shape were machined with same cross-section electrode material. Test parameters are material removal rate (MRR) and electrode wear ratio (EWR). Experiment results show slight difference in MRR and EWR values for different shapes. U shape presents the highest MRR and the lowest EWR occurs in flat shape compared to cavity and L shapes. It can be concluded that flat and U shapes result in good EDM machining quality due to good dielectric flow and flushing conditions in the area of EDM machining.

2019 ◽  
Vol 26 (05) ◽  
pp. 1830008 ◽  
Author(s):  
K. P. MAITY ◽  
M. CHOUBEY

Electrical discharge machining (EDM) is an unconventional machining process used for machining of hard-to-cut materials. Both EDM and micro-EDM processes are extensively used for producing dies and molds, complex cavities, and 3D structures. In recent years, researchers have intensively focused on improving the performance of both micro-EDM and EDM processes. This paper reviews the research work carried out by the researchers on vibration-assisted EDM, micro-EDM, and wire EDM. The consolidated review of this research work enables better understanding of the vibration-assisted EDM process. This study also discusses the influence of vibration parameters such as vibration frequency and amplitude on the material removal rate (MRR), electrode wear rate (EWR), and surface roughness (SR). The important issues and research gaps in the respective area of research are also presented in this paper.


2020 ◽  
Vol 38 (9A) ◽  
pp. 1406-1413
Author(s):  
Yousif Q. Laibia ◽  
Saad K. Shather

Electrical discharge machining (EDM) is one of the most common non-traditional processes for the manufacture of high precision parts and complex shapes. The EDM process depends on the heat energy between the work material and the tool electrode. This study focused on the material removal rate (MRR), the surface roughness, and tool wear in a 304 stainless steel EDM. The composite electrode consisted of copper (Cu) and silicon carbide (SiC). The current effects imposed on the working material, as well as the pulses that change over time during the experiment. When the current used is (8, 5, 3, 2, 1.5) A, the pulse time used is (12, 25) μs and the size of the space used is (1) mm. Optimum surface roughness under a current of 1.5 A and the pulse time of 25 μs with a maximum MRR of 8 A and the pulse duration of 25 μs.


Manufacturing ◽  
2003 ◽  
Author(s):  
Scott F. Miller ◽  
Albert J. Shih

The development of new, advanced engineering materials and the needs for precise and flexible prototype and low-volume production have made wire electrical discharge machining (EDM) an important manufacturing process to meet such demand. This research investigates the effect of spark on-time duration and spark on-time ratio, two important EDM process parameters, on the material removal rate (MRR) and surface integrity of four types of advanced material: porous metal foams, metal bond diamond grinding wheels, sintered Nd-Fe-B magnets, and carbon-carbon bipolar plates. An experimental procedure was developed. During the wire EDM, five types of constraints on the MRR due to short circuit, wire breakage, machine slide speed limit, and spark on-time upper and lower limits have been identified. An envelope of feasible EDM process parameters is created and compared across different work-materials. Applications of such process envelope to select process parameters for maximum MRR and for machining of micro features are presented.


2021 ◽  
Vol 1018 ◽  
pp. 51-58
Author(s):  
Tran Thi Hong ◽  
Nguyen Van Cuong ◽  
Bui Thanh Danh ◽  
Le Hong Ky ◽  
Nguyen Hong Linh ◽  
...  

This study aims to minimize electrode wear (EW) and maximize material removal rate (MRR) in powder mixed electrical discharge machining (PMEDM) process of 9CrSi alloy steel with silicon carbide powder. To achieve these objectives, Taguchi method and Grey Relational Analysis (GRA) are applied to optimize one two-level and four three-level PMEDM process parameters, including Ton, Toff, CP, IP and SV in eighteen experiments based on an orthogonal array L18 (21 and 43). Results have provided a set of optimal PMEDM process parameters in which Ton has the strongest effect on SW and MRR while that of CP is insignificant. The obtained minimum EW and maximum MRR have been verified and proven by a PMEDM experiment using optimal process parameters. The proposed method can be further applied to optimize other PMEDM process parameters for different objectives.


Author(s):  
Jin Zhang ◽  
Fuzhu Han

Abstract This paper proposed a new method of high-speed electrical discharge machining (EDM) using rotating short arcs under composite field. By the Lorentz force, the electric force and the high-speed rotation of the tool electrode, rotating short arcs are generated between the tool electrode and the workpiece, which can greatly improve the material removal rate of difficult-to-cut materials such as titanium alloys and superalloys. Firstly, the machining equipment used to generate rotating short arcs was constructed. Secondly, single arc discharge experiment was carried out to investigate the motion characteristics of rotating short arcs. The result shows that the arcs can rotate between the tool electrode and workpiece under composite field. Then, the experiment of processing GH4169 was conducted to explore the machining characteristics of rotating short arcs milling, which indicated that rotating short arcs can achieve a much higher material removal rate (MRR). Additionally, it’s found that the magnetic field also has influence on debris, which is beneficial to debris removal. Finally, a comparative experiment was carried out. The MRR of rotating short arcs milling was three times than that of traditional EDM, and the tool electrode wear rate (TEWR) is only one-fifth of that of traditional EDM. The comparative experiment further verified that rotating short arcs milling can achieve higher MRR and lower TEWR.


2014 ◽  
Vol 941-944 ◽  
pp. 2127-2133 ◽  
Author(s):  
Nirdesh Ojha ◽  
Florian Zeller ◽  
Claas Mueller ◽  
Holger Reinecke

The ability to machine advanced ceramic materials such as ZrO2, SiC, and AlN is of high interest for various industries because of the extraordinary material properties that these ceramics possess. Once sintered, these ceramics are characterized with high mechanical strength, high thermal stability and high chemical inertness. Therefore it is extremely difficult to machine these ceramics with dimensions in few microns using traditional techniques. Electrical discharge machining (EDM) is an electro-thermal machining process used to structure conductive materials. By applying a conductive layer on top of the non-conductive material, the EDM process can also be used to machine the non-conductive material. This paper presents a study on the effect of tool polarity and tool rotation on the material removal rate and electrode wear ratio during the EDM process of non-conductive SiC, ZrO2 and AlN ceramics. The reasons for the variation in the material removal rates among the different ceramics are examined by comparing the material properties. Relatively lower value of flexural strength, fracture toughness and melting temperature is the reason for AlN ceramic to have the higher MRR than SiC and ZrO2 ceramics.


Sign in / Sign up

Export Citation Format

Share Document