SU1301595A2 - Method of pulsed dimensional electrochemical working - Google Patents

Abstract

This invention relates to electrophysical and electrochemical processing methods. The purpose of the invention is the expansion of technological capabilities by using sources of pulsed technological voltage with a gentle back front in the conditions of forming the back front of a current pulse by reducing the electrical conductivity of the interelectrode gap during electrolyte boiling. At the time of generating the technological voltage pulse, the resistance of the interelectrode gap is controlled and when reaching bubble bubbling mode, as measured by the growth of the derivative of the voltage-to-current ratio, increases the voltage 2-3 times higher than the electrolyte provided effervescence and stop of the current (formation adjustable current pulse). 2 Il. i SL C JV with SL NJ

Description

The invention relates to electrophysical and electrochemical processing methods, in particular to methods of pulsed dimensional electrochemical processing, and is an improvement on the method according to the authors. St. No. 522937.

The purpose of the invention is to expand the technological capabilities of the method by applying unregulated sources of technological current.

Figure 1 shows a device for implementing the method; Fig. 2 shows voltage diagrams for the method.

 The device contains an electric holder 1, on which a processing electrode is fixed, a table 2 for fixing a part, a measurement unit 3

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The pulse voltage is of such a magnitude that the electrolyte boils within one field of the supply current wave. At the moment of action of the pulse, the current is measured by block 3 and, using block 4, the operating voltage is measured in the shape of the operating voltage. Block 5 calculates the resistance of the interelectrode gap as the ratio of the current to the voltage, then in block 6 subtracts the derivative of the obtained ratio, determines its sign, and if a positive increment is detected, a signal is given to turn on the additional source 7, as a result of which the voltage increases by 2-3 ra

After the additional source 7 is connected, a rapid ejection of the electrolyte occurs, which leads to flowing values of the current, unit 4, measuring-20 current jerking (pulses in fig. 2c).

nor current voltage values, block 5 for calculating the resistance of the interelectrode gap, block 6 for calculating the derivative, additional source 7 for voltage, source 8 for process voltage.

Fig. 2a shows the voltage developed by the process voltage source 8. The No. 4 pulses have a steep leading front (the moment thyristors are turned on in the rectifier) and a gentle falling front (the shutdown of the source valves is not adjustable). Fig. 26 shows the voltage developed by the additional source 7. This voltage is chosen 2-3 times greater than the voltage of the source 8. Fig. 2c shows the current pulses when implementing the method. The falling edge of the current pulses coincides with the moment of action of the additional source 7.

After installing the necessary interelectrode gap between, the electrode and the part turn on the source 8 of the technological voltage with the advance

The pulse voltage is of such a magnitude that the boiling of the electrolyte occurs during one half-wave of the supply current. At the moment of action of the pulse, the current value is measured by block 3 and the value of the operating voltage by block 4. Block 5 calculates the resistance of the interelectrode gap as the ratio of current to voltage, then in block 6 calculates the derivative of the ratio obtained, determines its sign, and if a positive increment is detected, it gives a signal to turn on an additional source 7, as a result of which the voltage increases 2-3 times.

After the additional source 7 is connected, the electrolyte boils rapidly, which leads to

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Using the proposed method allows processing at high current densities, which improves the processing accuracy.

The achievable effect of switching current due to the forced displacement of electrolyte during boiling expands the technological capabilities of the method, since the use of sources of technological voltage is not limited by the quality of the formation of the trailing edge of pulses.

the invention

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The method of pulse dimensional electrochemical processing according to ed. St. No. 522937, similar to the fact that, in order to expand technological capabilities, at the time of increasing the derivative ratio of the technological voltage to current, the technological voltage is boosted 2-3 times.

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Editor A. Kozoriz

Compiled by R. Melder

Tehred A. Kravchuk Proofreader M.Samborsk

Order 1181/14 Circulation 976 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

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Claims (1)

Claim The method of pulsed dimensional electrochemical processing according to ed. St. No. 522937, characterized in that, in order to expand technological capabilities, at the time of increasing the derivative of the ratio of technological voltage to current, they increase the technological voltage by 2-3 times. 13 015 95 Figure 1