Experimental Research on Small Holes by Electrical Discharge Machining Combined with Ultrasonic Vibration and Assisted Inwall Polish with the Ultrasonic Vibrating

2007 ◽  
Vol 359-360 ◽  
pp. 374-378
Author(s):  
Ming Rang Cao ◽  
Shi Chun Yang ◽  
Wen Hui Li ◽  
Sheng Qiang Yang
Keyword(s):  
Surface Roughness ◽  
Machine Tool ◽  
Surface Quality ◽  
Ultrasonic Vibration ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Small Hole ◽  
Tool Electrode ◽  
One Machine

The EDM can machined some superhard conducting material that cannot be handled by the traditional method, such as carbide alloy, tool steel and engineering materials etc., however, it is also accompanied with slow material removal rate(MRR) and poor surface quality (surface roughness). For some fine machining having rigorous criterion on size and surface roughness, the EDM cannot meet the demand. Some researches indicate that the MRR of small hole by electrical discharge machining combined with ultrasonic vibration (UEDM) can increase in certain range, but the surface quality is still poor. Although there are lots of the researches on the UEDM, some debates on machining mechanism and applied scope existed, and technology of UEDM needs the further study. After small hole machined by the UEDM, it is polished by ultrasonic vibrating. Two steps are includes in this technology. In the first place, on a high velocity electro discharge small hole machine with high-pressure dielectric liquid and hollow electrode, a transducer and horn are attached between the spindle and the electrode. The ultrasonic vibration of the tool electrode is implemented by connecting the horn and the tool electrode together with a chucking appliance. The second, after the small hole is complete, with the same machine tool and tool electrode the process of polishing the inwall of the small hole is carried out by accompanying the ultrasonic vibration, revolution and feed of the tool electrode with the abrasive material. In the experiments, the reference point for UEDM is found and the new theory is proposed to explain the increase of the MRR and the decrease of the surface roughness value .The polish with the ultrasonic vibration can improve further the surface roughness. The ultrasonic vibrating polish after the hole by UEDM is an economical and effective technology, which realizes machining of two procedures in one machine tool. So the process for changing machine tool and tool is not needed any more and the efficiency is further improved.

scholarly journals Research on Ultrasonic Vibration Assisted Electrical Discharge Machining SiCp/Al Composite

2021 ◽  
Author(s):  
Xiang Gao ◽  
Jucai Li ◽  
Qixuan Xing ◽  
Qinhe Zhang
Keyword(s):  
Surface Roughness ◽  
Flow Field ◽  
Ultrasonic Vibration ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Pulse Interval ◽  
Tool Electrode ◽  
Gap Flow ◽  
Al Composite

Abstract In this paper, ultrasonic-vibration assisted electrical discharge machining (UEDM) is used to process SiCp/Al composite materials in order to achieve a higher material removal rate (MRR) and lower surface roughness, width overcut, and relative tool wear rate (RTWR). FLUENT software was used to simulate the gap flow field. The simulation results of the gap flow field show that the ultrasonic vibration of the tool electrode is conducive to the removal of chips, which makes the discharge more stable and improves the machining efficiency. Based on the single factor experiment, the effects of peak current, reference voltage, pulse width, and pulse interval on MRR, surface roughness, width overcut, and RTWR of the workpiece are studied. Then, based on the orthogonal experiment, the grey relational analysis method was used to optimize the process parameters, and the order of the influence of the 4 process indicators on the comprehensive performance and the optimal processing parameter combination was obtained. The reliability of the process optimization was verified with experiments.

Study on the improvement of the surface integrity and efficiency of electrical-discharge-machined TC4 titanium alloy via abrasive flow machining

2020 ◽  
pp. 095440542097109
Author(s):  
Ze Yu ◽  
Dunwen Zuo ◽  
Yuli Sun ◽  
Guohua Li ◽  
Xuemei Chen ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Titanium Alloy ◽  
Surface Quality ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Small Hole ◽  
Machining Process ◽  
Machining Efficiency ◽  
Abrasive Flow Machining ◽  
Tc4 Titanium Alloy

To simultaneously optimize the surface quality and machining efficiency of the electrical discharge machining (EDM) processes used to produce titanium alloy quadrilateral group small hole parts, a combined “EDM + AFM” machining technology is proposed in this paper as an efficient and high-quality machining approach. In the proposed method, TC4 titanium alloy is first machined using the EDM process with graphite electrodes and the abrasive flow machining (AFM) process is then used to finish the machined surface. The effects of various electrical parameters on EDM-derived surface quality and improvements in EDM-derived quality under the application of AFM were assessed and, using the final surface roughness as a constraint condition, the effects of various combinations of EDM and “EDM + AFM” on efficiency were studied. The results revealed that the thickness and surface roughness of the superficial recast layer of the TC4 titanium alloy increase with both current and pulse width; in particular, increasing these parameters can increase the surface roughness by two to three grades. Following AFM, the alloy has a more uniform hardness distribution and the surface stress state changes from tensile to compressive stress, indicating that the combined “EDM + AFM” machining scheme can significantly enhance the surface quality of EDM-produced titanium alloy quadrilateral small group holes. The combined scheme achieves a balancing point beyond which increasing the roughness or the number of machining holes enhances either the machining efficiency or the machining surface quality. In the case of typical titanium alloy quadrilateral group small hole parts, the combined machining process can improve the finishing efficiency and total machining efficiency by 71.2% and 25.36%, respectively.

Experimental Research on Technology of Ultrasonic Vibration Aided Electrical Discharge Machining (UEDM) in Gas

2006 ◽  
Vol 315-316 ◽  
pp. 81-84 ◽  
Author(s):  
Qin He Zhang ◽  
Jian Hua Zhang ◽  
Q.B. Zhang ◽  
Shu Peng Su
Keyword(s):  
Ultrasonic Vibration ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Machining Parameters ◽  
Environment Pollution ◽  
Dielectric Fluids

Ultrasonic vibration aided electrical discharge machining (UEDM) in gas is an electrical discharge machining (EDM) technology, in which gases such as air and oxygen are used as dielectrics and ultrasonic vibration is applied. UEDM in gas can avoid environment pollution, the most serious disadvantage of conventional EDM in kerosene-based oil or other dielectric fluids, and it is environmental-friendly. The technology also possesses virtues of wide applications, high machining efficiency and simple tool electrodes and so on. The principle of UEDM in gas is introduced in this paper. Experiments have been carried out to study the effects of machining parameters on material removal rate (MRR), surface roughness of the workpiece and tool electrode wear ratio (TWR), and the experiments results have also been analyzed.

Dry WEDM in Improving LS-WEDMed Surface Quality

2008 ◽  
Vol 53-54 ◽  
pp. 387-392 ◽  
Author(s):  
Tong Wang ◽  
Yu Mei Lu ◽  
Shu Qiang Xie ◽  
Shuang Shuang Hao ◽  
H. Zhao
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Wire Electrical Discharge Machining ◽  
Dry Wedm ◽  
Cut Surface ◽  
Discharge Gap

Utilizing gas as the dielectric instead of dielectric liquid has enabled the development of dry wire electrical discharge machining (dry WEDM) technology for finishing cut. Experiment results showed that Low-Speed WEDM (LS-WEDM) in gas offers advantages such as better straightness, and shorter discharge gap. This paper studies on influence of different gas dielectrics, wire winding speed and pulse duration on the WEDMed surface quality (discharge gap, straightness, surface roughness, removal rate) in finishing. New attempt of applying dry WEDM as the 4th cut had been proved feasible in improving conventional multiple cut surface quality of LS-WEDM.

The Mechanism of Ultrasonic Vibration Improving MRR in UEDM in Gas

2004 ◽  
Vol 471-472 ◽  
pp. 741-745 ◽  
Author(s):  
Qin He Zhang ◽  
Ru Du ◽  
Jian Hua Zhang ◽  
J.Y. Yang ◽  
Sheng Feng Ren
Keyword(s):  
Ultrasonic Vibration ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Machining Process ◽  
Tool Electrode ◽  
Metallic Liquid ◽  
Liquid Drops ◽  
Effective Discharge ◽  
Gas Medium

A new machining method, ultrasonic vibration aided electrical discharge machining (UEDM) in gas, is proposed in this paper. It is shown that electrical discharge machining with ultrasonic vibration aid can be achieved well in gas medium. In the process of UEDM in gas, the tool electrode is formed to be thin-walled pipe, high pressure gas medium is supplied from inside, and ultrasonic vibration is applied to workpiece. The property of ultrasonic is introduced. The same to other sound waves, ultrasonic have the characteristics of reflecting, refracting, intervening and resonance. The mechanism of elastic pole keeping in resonance with ultrasonic transferring from one end to the other end is explained with characteristics of ultrasonic. During the process of UEDM in gas, ultrasonic vibration of workpiece can improve the machining process. The theories of ultrasonic vibration increasing materials removal rate (MRR) are introduced. One theory is that the adhere strength between the metallic liquid drops and workpiece is not enough for the accelerative vibration, so metallic liquid drops will be ejected off easily. Another theory is that ultrasonic vibration increases the number of the effective discharge.

Study on Finishing Cut with Dry WEDM

2006 ◽  
Vol 532-533 ◽  
pp. 273-276 ◽  
Author(s):  
Tong Wang ◽  
Xin Fu Zhang ◽  
Xue Fang Zhao
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Lower Surface ◽  
Wire Electrical Discharge Machining ◽  
Dry Wedm

Utilizing gas as the dielectric instead of dielectric liquid has enabled the development of dry wire electrical discharge machining (WEDM) technology for finishing cut. This paper studies on the surface quality of tool steel with WEDM method, which is conducted in gas to improve the accuracy of finishing cut, and compares the surface quality in atmosphere and in water. Experiment results showed that Low-Speed WEDM in atmosphere offers advantages such as better straightness, lower surface roughness and shorter gap length, but WEDM in atmosphere has poorer material removal rate than conventional WEDM in water. It was also found the removal rate in atmosphere can be improved by increasing the wire winding speed.

Effect of SiC-Cu Electrode on Material Removal Rate, Tool Wear and Surface Roughness in EDM Process

2020 ◽  
Vol 38 (9A) ◽  
pp. 1406-1413
Author(s):  
Yousif Q. Laibia ◽  
Saad K. Shather
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Material Removal Rate ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
304 Stainless Steel ◽  
Tool Electrode ◽  
Pulse Time ◽  
Edm Process

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.

Optimization of μEDM process assisted with rotating magnetic pulling force and ultrasonic vibration

2021 ◽  
pp. 095440892098440
Author(s):  
Gurpreet Singh ◽  
DR Prajapati ◽  
PS Satsangi
Keyword(s):  
Ultrasonic Vibration ◽  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Machining Process ◽  
Micro Electrical Discharge Machining ◽  
Pulling Force ◽  
Tool Rotation

The micro-electrical discharge machining process is hindered by low material removal rate and low surface quality, which bound its capability. The assistance of ultrasonic vibration and magnetic pulling force in micro-electrical discharge machining helps to overcome this limitation and increase the stability of the machining process. In the present research, an attempt has been made on Taguchi based GRA optimization for µEDM assisted with ultrasonic vibration and magnetic pulling force while µEDM of SKD-5 die steel with the tubular copper electrode. The process parameters such as ultrasonic vibration, magnetic pulling force, tool rotation, energy and feed rate have been chosen as process variables. Material removal rate and taper of the feature have been selected as response measures. From the experimental study, it has been found that response output measures have been significantly improved by 18% as compared to non assisted µEDM. The best optimal combination of input parameters for improved performance measures were recorded as machining with ultrasonic vibration (U1), 0.25 kgf of magnetic pulling force (M1), 600 rpm of tool rotation (R2), 3.38 mJ of energy (E3) and 1.5 mm/min of Tool feed rate (F3). The confirmation trail was also carried out for the validation of the results attained by Grey Relational Analysis and confirmed that there is a substantial improvement with both assistance applied simultaneously.

scholarly journals The Effect of Discharge Current and Pulse-On Time on Biocompatible Zr-based BMG Sinking-EDM

2020 ◽  
Vol 10 (1) ◽  
pp. 401-407
Author(s):  
Yanuar Rohmat Aji Pradana ◽  
Aldi Ferara ◽  
Aminnudin Aminnudin ◽  
Wahono Wahono ◽  
Jason Shian-Ching Jang
Keyword(s):  
Surface Roughness ◽  
Metallic Glasses ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Surface Hardness ◽  
Recast Layer ◽  
Surface Evaporation ◽  
Pulse On Time

AbstractThe machinability information of Zr-based bulk metallic glasses (BMGs) are recently limited but essential to provide technological recommendation for the fabrication of the medical devices due to the material’s metastable nature. This study aims to investigate the material removal rate (MRR) and surface roughness under different current and pulse-on time of newly developed Ni- and Cu-free Zr-based BMG using sinking-electrical discharge machining (EDM). By using weightloss calculation, surface roughness test and scanning electron microscopy (SEM) observation on the workpiece after machining, both MRR and surface roughness were obtained to be increased up to 0.594 mm3/min and 5.50 μm, respectively, when the higher current was applied. On the other hand, the longer pulse-on time shifted the Ra into the higher value but lower the MRR value to only 0.183 mm3/min at 150 μs. Contrary, the surface hardness value was enhanced by both higher current and pulse-on time applied during machining indicating different level of structural change after high-temperature spark exposure on the BMG surface. These phenomena are strongly related to the surface evaporation which characterize the formation of crater and recast layer in various thicknesses and morphologies as well as the crystallization under the different discharge energy and exposure time.

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