CN108793054A - A kind of micro-nano electrode preparation facilities and preparation method based on bidirectional pulse power supply - Google Patents

Abstract

The invention provides a micro-nano electrode preparation device and a preparation method based on a bidirectional pulse power supply. The preparation device includes: a working table, an electrolyte tank, a convex support block, a bidirectional pulse power supply, a connecting shaft, a platinum metal ring, a horizontal support arm and a vertical support arm. The preparation method steps include: loading potassium hydroxide solution in the electrolytic solution tank, and making the liquid level of the potassium hydroxide solution higher than the installation height of the platinum metal ring; clamping the upper end of the electrode rod on the clamp, and the lower end of the electrode rod Through the central ring hole of the platinum metal ring, the electrode rod is set concentrically with the central ring hole of the platinum metal ring; the positive pulse with a pulse width of 100ns‑150ns is alternately sent to the collet and sent to the platinum metal ring by using a bidirectional pulse power supply cycle A reverse pulse with a pulse width of 150ns-160ns to etch the electrode rod. The preparation device and method of the micro-nano electrode can reduce the taper of the prepared nano-electrode by only using a bidirectional pulse power supply without applying any external motion.

Description

A kind of micro-nano electrode preparation device and preparation method based on bidirectional pulse power supply

technical field

The invention relates to a micro-nano electrode preparation device and a preparation method, in particular to a micro-nano electrode preparation device and a preparation method based on a bidirectional pulse power supply.

Background technique

Micro-nano-scale electrodes are a necessary condition for microfabrication. At present, the methods for preparing micro-nano electrodes mainly include mechanical shearing, focused ion milling, and electrolytic machining. Electrodes prepared by mechanical shearing are mainly tapered electrodes, which have a low success rate and are difficult to guarantee the preparation accuracy. Focused ion milling can prepare electrodes with various shapes, but focused ion milling equipment is expensive, processing efficiency is low, and electrode preparation costs are high. Electrolytic machining is currently the most commonly used method for preparing micro-nano electrodes, and the size of the electrodes is controllable and relatively simple.

Using the electrolytic machining method, due to the accumulation of electrolytic products during the machining process, the processed tool electrode is in the shape of a large and small pointed cone. This cone-shaped electrode limits its machining accuracy to a certain extent. If the electrodes of this shape are used for electrolytic drilling, the side walls of the processed holes will have a large taper. In order to reduce the taper of the prepared electrode and increase the aspect ratio of the electrode, various movements are often applied during the processing, so that the distribution of electrolytic products tends to be uniform. Use piezoelectric ceramics to vibrate the electrolyte film up and down at a frequency of _35HZ in the process of electrolytic processing to reduce the influence of the diffusion layer on the electrode shape, thereby reducing the taper of the nano-electrode, but this requires additional equipment in the electrode preparation device. Equipped with vibration system.

Contents of the invention

The technical problem to be solved by the present invention is that the existing preparation device and preparation method require additional auxiliary devices and increase the preparation cost.

In order to solve the above technical problems, the present invention provides a micro-nano electrode preparation device based on a bidirectional pulse power supply, including a worktable, an electrolyte tank, a convex support block, a bidirectional pulse power supply, a connecting shaft, a platinum metal ring, and a transverse support arm and vertical support arm; the electrolyte tank is arranged on the worktable, and the vertical support arm is vertically fixedly installed on the worktable; one end of the horizontal support arm is fixedly installed on the vertical support arm through the first mounting bolt; One end of the shaft is fixedly installed on the other end of the horizontal support arm through the second mounting bolt; the connecting shaft is parallel to the vertical support arm; the convex support block is fixedly installed in the electrolyte tank, and the platinum metal ring is installed horizontally on the convex support shaped bracket block, and the platinum metal ring is located in the electrolyte tank; the lower end of the connecting shaft points to the central ring hole of the platinum metal ring; the lower end of the connecting shaft is provided with a chuck for clamping and fixing the electrode rod; the bidirectional pulse power supply The positive end is electrically connected to the chuck through a waterproof wire; the negative end of the bidirectional pulse power supply is electrically connected to the platinum metal ring through a waterproof wire.

Further, the thickness of the ring piece of the platinum metal ring is 2-3 mm, and the diameter of the central ring hole is 6-7 mm.

Further, the following steps are included:

Step 1, loading potassium hydroxide solution in the electrolytic solution tank, and making the liquid level of the potassium hydroxide solution higher than the installation height of the platinum metal ring;

Step 2, the upper end of the electrode rod is clamped on the chuck, and the lower end of the electrode rod passes through the central ring hole of the platinum metal ring, and the electrode rod and the central ring hole of the platinum metal ring are arranged concentrically;

Step 3, using a bidirectional pulse power supply to alternately send forward pulses with a pulse width of 100 ns-150 ns to the chuck and send reverse pulses with a pulse width of 150 ns-160 ns to the platinum metal ring, so as to etch the electrode rod.

Further, the solubility of the potassium hydroxide solution loaded in the electrolyte tank is 1.5 mol/L.

The beneficial effect of the present invention is that: in order to obtain a better length-to-diameter ratio, measures should be taken to make the distribution of electrolytic products around the electrode rod tend to be uniform. The taper of the nano-electrode is prepared; during the forward pulse, the electrode rod as the anode is electrochemically dissolved, and the product moves down under the action of gravity and accumulates around the electrode rod, forming a cone-shaped accumulation; when the reverse pulse is applied, the electrode The rod acts as the cathode to generate hydrogen gas. The formation and escape of hydrogen bubbles disturb the electrolysis products accumulated around the electrode rod during the positive pulse, making the product distribution tend to be uniform or dispersed in the electrolyte, making the conductivity around the electrode rod tend to be It is uniform and repeated so that the prepared tool electrode has a good aspect ratio.

Description of drawings

1 is a schematic diagram of the overall structure of the micro-nano electrode preparation device of the present invention;

Fig. 2 is the distribution situation of the electrolysis product around the tungsten rod when Fig. 2 is positive pulse;

Fig. 3 shows the distribution of electrolytic products around the tungsten rod during the reverse pulse of the present invention.

Detailed ways

As shown in Figure 1, the micro-nano electrode preparation device based on bidirectional pulse power supply provided by the present invention includes: worktable 1, electrolyte tank 2, convex support block 4, bidirectional pulse power supply 6, connecting shaft 9, platinum metal ring 12. The horizontal support arm 13 and the vertical support arm 15; the electrolyte tank 2 is arranged on the worktable 1, and the vertical support arm 15 is vertically fixedly installed on the worktable 1; one end of the horizontal support arm 13 passes through the first Mounting bolt 14 is fixedly installed on the vertical support arm 15; One end of connection shaft 9 is fixedly installed on the other end of transverse support arm 13 by second mounting bolt 8; Connection shaft 9 is parallel with vertical support arm 15; Convex support The block 4 is fixedly installed in the electrolyte tank 2 through the screw 3, the platinum metal ring 12 is horizontally installed on the convex support block 4 through the cantilever, and the end of the cantilever is installed on the convex support block 4 through the screw 3, and the platinum metal ring 12 is located in the electrolyte tank 2; the lower end of the connecting shaft 9 points to the central ring hole of the platinum metal ring 12; the lower end of the connecting shaft 9 is provided with a chuck 10 for clamping and fixing the electrode rod 11; the positive side of the bidirectional pulse power supply 6 The extreme end is electrically connected to the chuck 10 through the waterproof wire 7; the negative end of the bidirectional pulse power supply 6 is electrically connected to the platinum metal ring 12 through the waterproof wire 7. The ring piece thickness of the platinum metal ring 12 is 2-3mm, and the diameter of the central ring hole is 6-7mm.

The micro-nano electrode preparation method based on bidirectional pulse power supply provided by the present invention comprises the following steps:

Step 1, loading potassium hydroxide solution in electrolyte tank 2, and make the liquid level of potassium hydroxide solution 5 higher than the installation height of platinum metal ring 12, the solubility of potassium hydroxide solution 5 is 1.5mol/L;

Step 2, the upper end of the electrode rod 11 is clamped on the chuck 10, and the lower end of the electrode rod 11 passes through the central ring hole of the platinum metal ring 12, and the electrode rod 11 and the central ring hole of the platinum metal ring 12 are arranged concentrically;

Step 3, use the bidirectional pulse power supply 6 cycles to alternately send forward pulses with a pulse width of 100ns-150ns to the chuck 10 and send reverse pulses with a pulse width of 150ns-160ns to the platinum metal ring 12, that is, send pulses to the chuck 10 After the forward pulse with a width of 100ns-150ns, a reverse pulse with a pulse width of 150ns-160ns is sent to the platinum metal ring 12, so that the cycle alternates, the amplitude of the forward pulse and the reverse pulse is 4V, so that the electrode rod 11 for etching, when the positive pulse, the electrode rod 11 is gradually etched in the electrolyte tank 2 due to the electrolytic reaction, and the electrolytic products are accumulated around the electrode rod 11, forming a small upper part and a larger lower part due to the action of gravity. distribution state, as shown in Figure 2; when the reverse pulse is applied, the electrode rod 11 is equivalent to the negative pole connected to the power supply, and a large number of bubbles are generated. The floating and bursting of the bubbles disturb the electrolytic product around the electrode rod 11, making The distribution of electrolytic products around the electrode rod 11 tends to be uniform, as shown in FIG. 3 , and the cycle repeats itself, so that the taper of the prepared micro-nano electrode is smaller.

Claims (4)

1. A micro-nano electrode preparation device based on a bidirectional pulse power supply, characterized in that it comprises a worktable (1), an electrolyte tank (2), a convex support block (4), a bidirectional pulse power supply (6), a connection Shaft (9), platinum metal ring (12), transverse support arm (13) and vertical support arm (15); electrolyte tank (2) is arranged on the worktable (1), vertical support arm (15) Vertically fixedly installed on the workbench (1); one end of the horizontal support arm (13) is fixedly installed on the vertical support arm (15) by the first mounting bolt (14); one end of the connecting shaft (9) passes through the second Mounting bolts (8) are fixedly mounted on the other end of the horizontal support arm (13); the connecting shaft (9) is parallel to the vertical support arm (15); the convex support block (4) is fixedly mounted on the electrolyte tank (2 ), the platinum metal ring (12) is installed horizontally on the convex support block (4) through a cantilever, and the platinum metal ring (12) is located in the electrolyte tank (2); the lower end of the connecting shaft (9) points to the platinum metal ring (12) in the central ring hole; the lower end of the connecting shaft (9) is provided with a chuck (10) for clamping and fixing the electrode rod (11); the positive end of the bidirectional pulse power supply (6) passes through the waterproof wire (7) It is electrically connected with the chuck (10); the negative terminal of the bidirectional pulse power supply (6) is electrically connected with the platinum metal ring (12) through a waterproof wire (7). 2. The micro-nano electrode preparation device based on bidirectional pulse power supply according to claim 1, characterized in that, the ring sheet thickness of the platinum metal ring (12) is 2-3mm, and the diameter of the central ring hole is 6-7mm. 3. the preparation method of the micro-nano electrode preparation device based on bidirectional pulse power supply according to claim 1, is characterized in that, comprises the steps: Step 1, loading potassium hydroxide solution in the electrolytic solution tank (2), and making the liquid level of the potassium hydroxide solution higher than the installation height of the platinum metal ring (12); Step 2, clamp the upper end of the electrode rod (11) on the chuck (10), and the lower end of the electrode rod (11) passes through the central ring hole of the platinum metal ring (12), the electrode rod (11) and the platinum metal ring (12) The central ring hole is set with the coaxial center; Step 3, using the bidirectional pulse power supply (6) to periodically alternately send forward pulses with a pulse width of 100ns-150ns to the chuck (10) and send reverse pulses with a pulse width of 150ns-160ns to the platinum metal ring (12), thereby The electrode rod (11) is etched. 4. the preparation method of the micro-nano electrode preparation device based on bidirectional pulse power supply according to claim 3, is characterized in that, the solubility of the potassium hydroxide solution loaded in electrolyte tank (2) is 1.5mol/L.