Research of Pulse Inversion Power Supply of ECM and its Techniques

2009 ◽  
Vol 76-78 ◽  
pp. 630-634 ◽  
Author(s):  
Yong Jun Zhang ◽  
Yong Jun Tang ◽  
Zhong Ning Guo ◽  
Xiao Kang Liu ◽  
Feng Li

In order to improve machining accuracy and surface quality effectively in ECM (electrochemical machining), a novel pulse inversion power supply has been presented, which has following merits such as high-frequency short pulse, high-power, and compact size. The scheme of full bridge inversion has been selected in this power supply model, and feedback circuit realizes voltage adjusted automatically, and guarantees to stability of voltage. Protect circuit has designed to avoid the problem of workpiece-burn. Finally, a series of electrochemical mechanical polishing tests using the power supply have been carried out, and the results have proved that it helps to achieve well surface quality processed, and improve machining accuracy, and also verify feasibility of its scheme.

2010 ◽  
Vol 97-101 ◽  
pp. 2505-2508 ◽  
Author(s):  
Yuan Bo Li ◽  
Yong Jun Zhang ◽  
Zhong Ning Guo

A micro Electrochemical Machining (ECM) system has been developed, and macro/micro complex feed mechanism has been presented in order to achieve high-resolution. A nanosecond pulse power supply for micro-ECM has been developed, and the minimum pulse width can reach 50 ns. Complementary chopper circuit has been designed to avoid waveform distortion, which can achieve higher pulse frequency. A series of ECM experiments using the machining system have been carried out, and results of tests have proved that high-resolution spindle, and high frequency, short pulse width power supply help to achieve better quality surface, higher machining accuracy.


2009 ◽  
Vol 626-627 ◽  
pp. 369-374 ◽  
Author(s):  
Yong Jun Zhang ◽  
Yong Jun Tang ◽  
Xiao Kang Liu ◽  
Z.N. Guo ◽  
F. Li

A nanosecond pulse power supply for micro-ECM (Electrochemical Machining) has been developed, and the minimum pulse on-time is 50 ns. After the influence of ultra-short pulse on micro-ECM was analyzed, complementary chopper circuit was presented to avoid waveform distortion, which can achieve higher pulse frequency. A fast protect circuit was designed, and its response time is less than 5μs, which can avoid damaging workpiece and electrical components by switching off machining voltage and step motor as soon as a short circuit was detected. A series of ECM experiments using the power supply have been carried out, and results of test have proved that high frequency, short pulse width power supply helps to achieve better quality surface, higher machining accuracy.


2013 ◽  
Vol 395-396 ◽  
pp. 1062-1065 ◽  
Author(s):  
Xiao Hai Li ◽  
Li Ping Zhao ◽  
Ying Chun Shi ◽  
Li Jie Zhao

Electrochemical machining (ECM) is an anodic dissolution process of metal as anode ion by ion, and micro-ECM is a promising micromachining method at micro to meso-scale. Thus, a micro-ECM setup was developed to fabricate micro parts and explore the feasibility of micro-ECM at micro to meso-scale, including the design of high-frequency micro-energy pulse power supply. By using the detection unit of machining state and optical encoder, a closed loop control system for micro-ECM was developed. Under low concentration of passivating electrolyte, low machining voltage, micro rotating electrode and high-frequency short-pulse current, the machining gap can be reduced to about 10μm. The influence factors of the additives and the rotation of micro electrode on micro ECM were analysed by experiments. A micro-hole about 30μm in diameter was drilled by the rotating micro electrode.


Author(s):  
Zhaolong Li ◽  
Bingren Cao

Background: High-temperature alloy such as nickel-based alloy has become the main material for core components such as aero engines due to their high strength and good toughness. Therefore, it is of great significance to study how to improve the machining accuracy and stability of electrochemical machining (ECM) of deep small holes on the nickel-based alloy. The instantaneous high-density current during the pulse width of pulse ECM is beneficial to the dissolution of metal workpieces. Many experts and scholars have studied the pulse ECM of deep small holes. Objective: The purpose of this article is to propose and design a Positive And Negative Pulse (PANP) power supply to study the accuracy and stability of ECM of deep small holes on nickel-based alloys. Methods: First of all, an H-bridge composed of four MOSFET switches is designed to achieve PANP output in the main circuit of the power supply. Then, this paper studies the influence of the ratio of positive and negative pulses on short circuits, the influence of the ratio of positive and negative pulses on the mass removal rate, and the influence of the electrolyte concentration and pulse width on the mass removal rate. Finally, according to the obtained optimal parameters, the influence of electrolyte pressure on the average radial overcut of hole depth is analyzed. Results: The experimental results showed that the short-circuit frequency is reduced by more than 50% compared with non-negative pulse power supply; the ratio of positive and negative pulses, pulse width and electrolyte concentration and pressure were optimized by experiments to improve the mass removal rate of the workpiece and the average radial overcut of hole depth. Conclusion: The designed PANP power supply can improve the machining accuracy and stability of ECM of deep small holes on nickel-based alloys.


2011 ◽  
Vol 130-134 ◽  
pp. 3320-3323
Author(s):  
Guo Qiang Cao ◽  
Yi Tong Dai ◽  
Lan Yao

Recently, high frequency short pulse electrochemical machining is a focus engineering of national research, its mechanism of research must established in the foundation of correct mathematics model, capacitance model is a ideal model to analysis high frequency short pulse, this article is based on capacitance model, make a detailed formula deduction on the main factors for high frequency short pulse electrochemical machining, eventually, acquired high frequency narrow pulse electrolysis processing gap between poles formula which is based on capacitance model.


2011 ◽  
Vol 295-297 ◽  
pp. 834-839 ◽  
Author(s):  
Yong Wei Zhu ◽  
Xing Lei Miao ◽  
Chao Feng Zhang

The micro-PECM (Pulse Electrochemical Machining) combining synchronous ultrasonic vibration is proposed as a new technology for to solve the difficulty machining problems of conductive hard and tough materials. The feasibility of micro-PECM combining synchronous ultrasonic vibration is studied. The synchronous way is analyzed; the synchronous electrical circuit is designed and made. The synchronous electrochemical micro-machining system combining ultrasonical vibration are built and improved,which machining parameters can be adjusted in a wide ranges, and the synchronous target of the ultrasonical vibration with the voltage of micro-PECM can be realized. The micro-machining electrodes are manufactured in different sections and sizes by combined electrical discharge machining. The mechanism tests of micro-PECM are carried, which kentaniums (YBD151、YG8)and stainless steel are machined and the results are analyzed and discussed. Contrast with the single micro-USM, the micro-PECM combining ultrasonic vibration has high productivity, good machining accuracy and surface quality; furthermore, its cathode wastage is low. The micro-PECM combining synchronous ultrasonic vibration has the best machining precision and surface quality.


2010 ◽  
Vol 455 ◽  
pp. 653-657 ◽  
Author(s):  
Cheng Guang Zhang ◽  
Y.Z. Hu ◽  
Bo Zhao

The application of ultrasonic polishing and machining pulse electrochemical machining compound finishing is presented in the paper. The machining principle and experimental set-up of UPM-PECM compound finishing are introduced in the paper, discussing mechanism and model of the UPM-PECM in theory, and carrying on the experiment, which would co-act on hard-brittle metals in the machining. Furthermore, the material removal depth of UPM-PECM compound finishing is approximately proportional to the polishing time, and would decrease with the polishing time. This study indicates that machining velocity, machining accuracy and surface quality can be improved under UPM-PECM.


2006 ◽  
Vol 315-316 ◽  
pp. 731-735
Author(s):  
Xiao Hai Li ◽  
Zhen Long Wang ◽  
Wan Sheng Zhao

Electrochemical machining (ECM) has been rarely applied in micromachining because the electric field is not localized. In order to explore the feasibility of applying ECM to micromachining at micro to meso-scale, an experimental setup with precision control over electrochemical micromachining (EMM) was developed, which is in fact a multifunctional machine tool. The micro tool electrodes for EMM can also be fabricated by micro electrical discharge machining (EDM) on the same machine tool. A high-frequency short-pulse micro-energy MOSFET power supply was designed. Lower machining voltage and lower concentration of passivity electrolyte are utilized together to localize dissolution area in EMM. A micro hole 45 ,m in diameter was drilled by EMM on stainless steel foil with 100 μm thickness. A new approach of fabricating microstructures by means of EMM milling using a simple micro tool electrode is proposed, and a shaped hole and a micro cantilever beam with high precision were acquired by EMM milling. The satisfactory process results indicate the potential capability of EMM for higher machining accuracy and smaller machining size.


2021 ◽  
Vol 11 (5) ◽  
pp. 2237
Author(s):  
Oh Heon Kwon ◽  
Won Bin Park ◽  
Juho Yun ◽  
Hong Jun Lim ◽  
Keum Cheol Hwang

In this paper, a low-profile HF (high-frequency) meandered dipole antenna with a ferrite-loaded artificial magnetic conductor (AMC) is proposed. To operate in the HF band while retaining a compact size, ferrite with high permeability is applied to the unit cell of the AMC. The operating frequency bandwidth of the designed unit cell of the AMC is 1.89:1 (19–36 MHz). Thereafter, a meandered dipole antenna is designed by implementing a binary genetic algorithm and is combined with the AMC. The overall size of the designed antenna is 0.06×0.06×0.002 λ3 at the lowest operating frequency. The proposed dipole antenna with a ferrite-loaded AMC is fabricated and measured. The measured VSWR bandwidth (<3) covers 20–30 MHz on the HF band. To confirm the performance of the antenna, a reference monopole antenna which operates on the HF band was selected, and the measured receiving power is compared with the result of the proposed antenna with the AMC.


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