CN107447243B - A device for one-way surface modification of metal micro-arc oxidation - Google Patents

Abstract

The invention relates to a device for metal micro-arc oxidation unidirectional surface modification and a use method thereof. The device comprises a fastening bolt, an insulating pressing ring, a rubber sealing ring, a sample, a conductive cushion block, a stainless steel shielding frame, an insulating plastic outer frame, a conductive bolt, an insulating sheath and an anode circuit connected with a micro-arc oxidation power supply. The beneficial effects of the invention are as follows: 1. the device has good tightness, can realize unidirectional surface modification of the sample and the workpiece, and solves the problems that local surface modification is required due to the limitation of material performance requirements. 2. The stainless steel shielding frame in the device can shield the interference of the power line, and can ensure experimental precision. 3. The device can be suitable for samples with different thicknesses by adjusting and replacing conductive cushion blocks with different thicknesses. 4. The device has the characteristics of simple structure, easy manufacture, high precision, strong reliability and the like. The method is very suitable for the micro-arc oxidation unidirectional surface modification of various samples.

Description

A device for one-way surface modification of metal micro-arc oxidation

technical field

The invention relates to the field of surface modification of micro-arc oxidation technology, in particular to a device for unidirectional surface modification of metal micro-arc oxidation.

Background technique

Micro-arc oxidation technology is a new type of metal surface treatment technology that has emerged in China in recent years. Its principle is to use plasma chemistry and The electrochemical principle produces a micro-area arc discharge phenomenon and then grows a layer of ceramic layer on the metal surface in situ, so that the material has a wider range of physical and chemical properties to meet the higher requirements of modern industry for materials.

During the micro-arc oxidation modification process, the entire sample needs to be immersed in the solution, and some materials only need to modify their single surface due to their unique structure, and other parts will cause corrosion or change their properties when they are in contact with the solution.

Contents of the invention

The purpose of the present invention is to solve the problem of partial surface modification due to the limitation of material performance requirements, and provide a device for unidirectional surface modification of metal micro-arc oxidation and its application method. It has the characteristics of simple structure, easy manufacture, high precision and strong reliability. It is very suitable for micro-arc oxidation unidirectional surface modification of various samples.

The technical scheme that the present invention solves the problems of the technologies described above is:

A device for one-way surface modification of metal micro-arc oxidation, the device consists of n fastening bolts 1, n insulating pressure rings 2, n rubber sealing rings 3, samples 4, conductive pads 5, stainless steel The shielding frame 6, the insulating plastic outer frame 7, the conductive bolt 8, the conductive bolt insulating sheath 9, and the anode line 10 connected to the micro-arc oxidation power supply are assembled;

After assembly, any one of the n fastening bolts 1 passes through its corresponding insulating pressure ring and extends into the insulating outer frame 7, and the stainless steel shielding frame 6 is located between the conductive pad and the insulating plastic outer frame 7 and in close contact with both;

After assembly, the conductive bolt is covered with an insulating sheath 9; it penetrates the insulating plastic outer frame 7 and the stainless steel shielding frame 6 from the bottom and is embedded in the hole reserved by the conductive pad 5; the conductive bolt is also connected with Connect the anode line 10 of the micro-arc oxidation power supply;

After assembly, assume that the device is cut along plane A to obtain section B. The plane A is perpendicular to the bottom surface of the insulating plastic outer frame 7 and passes through two insulating pressure rings; project along the direction perpendicular to section B to obtain a projection diagram , on the projection diagram, a single insulating pressure ring is in a "step" shape, and a single rubber sealing ring is in an inverted "convex" shape;

Definition: the distance from the bottom of the stainless steel shielding frame 6 on the projection diagram to the plane where the top of the insulating plastic frame 7 is located is L, and the distance from the bottom of the stainless steel shielding frame 6 on the projection diagram to the plane where the top of the stainless steel shielding frame 6 is located is P ;

Define the height of the conductive pad as H; said H is less than P, and P is less than L; define the height of the protruding part of a single rubber sealing ring as E, and the total height of the inverted "convex" type as F; then E+P=L ; Define the length of a single "step" as M, the total height as Q, the length of the step surface as R, the height of the first step as S, the height of the second step as T, and the length of the second step as U, then S+T=Q , R+U=M; Define the width of the insulating plastic outer frame 7 top as V, define the edge of a single "convex" type as W, then U+W=V; define the length of a single "convex" type bottom as X, Then X=R.

The invention is a device for one-way surface modification of metal micro-arc oxidation. After assembly, a sample 4 is fixed by a conductive pad 5 and a rubber sealing ring.

The invention is a device for unidirectional surface modification of metal micro-arc oxidation, wherein said n is selected from any integer in 3-8; preferably 6 or 4.

The present invention is a device for unidirectional surface modification of metal micro-arc oxidation. On the projection diagram, the width of a single "convex" top is defined as Y, which is consistent with the width of the top of the stainless steel shielding frame 6.

The invention is a device for unidirectional surface modification of metal micro-arc oxidation. On the projection diagram, the height E of the "convex"-shaped protruding part is equal to L-P.

The fastening bolts are M8 bolts with a diameter of 8mm, and the conductive bolts are M10 bolts with a diameter of 10mm. The outer diameter of the insulating pressure ring is 210 mm, and the inner diameter is 150 mm. Four uniform and symmetrical bolt holes with a diameter of 9 mm are drilled on the insulating pressure ring. The outer diameter of the insulating plastic outer frame is 210 mm, and the inner diameter is 170 mm. Drill M8 threaded holes at positions corresponding to the bolt holes on the insulating pressure ring, and drill 11 mm bolt holes at the center of the bottom. The stainless steel shielding frame has an outer diameter of 170mm and an inner diameter of 160mm, and an M10 threaded hole is drilled at the center of the bottom. The rubber sealing ring has an outer diameter of 180mm and an inner diameter of 150mm.

The sample is placed on a conductive pad, and a rubber sealing ring is put on the stainless steel shielding frame and the edge of the sample; the insulating pressure ring and the insulating plastic outer frame are connected and fastened by four fastening bolts.

The anode circuit of the micro-arc oxidation power supply is connected with conductive bolts.

A method for using a device for one-way surface modification of metal micro-arc oxidation, comprising the following steps:

Step 1: After the overall device is equipped, place the sample on the conductive pad, and then put a rubber sealing ring on the stainless steel shielding frame and the edge of the sample.

Step 2: Align the bolt through holes on the insulating pressure ring with the threaded holes of the insulating plastic frame, and tighten the fastening bolts so that the sealing rubber ring is in close contact with the sample.

Step 3: According to the thickness of the sample, the conductive pads of different thicknesses can be replaced to meet the experimental requirements.

Step 4: Connect the anode line of the micro-arc oxidation power supply at the conductive bolt.

Step 5: Place the device with the sample installed in the electrolytic cell, so that the surface of the sample is completely placed in the electrolyte, and adjust the appropriate depth to keep the sample parallel to the surface of the electrolyte.

Step 6: According to the pre-selected parameters, set the experimental parameters and experimental conditions, and turn on the power for micro-arc oxidation treatment.

The beneficial effects of the present invention are:

1. For the first time, the present invention adopts a rubber tight inverted "convex" sealing ring with an outer edge. Through its precise cooperation with fastening bolts, conductive pads, and stainless steel shielding frames, the perfect sealing of the device is realized, and further can be realized. One-way surface modification of samples and workpieces to solve problems such as local surface modification due to material performance requirements.

2. The stainless steel shielding frame in the device can shield the interference of the power line and ensure the accuracy of the experiment.

3. The device can be adjusted to replace conductive pads of different thicknesses and is suitable for samples of different thicknesses.

4. The device has the characteristics of simple structure, easy manufacture, high precision and strong reliability. It is very suitable for micro-arc oxidation unidirectional surface modification of various samples.

Description of drawings

Fig. 1 is a schematic structural view of the device for unidirectional surface modification of metal micro-arc oxidation according to the present invention.

Fig. 2 is the sketch map of projection;

Fig. 3 is the sketch map of partial projection;

In the figure: 1 fastening bolt, 2 insulating pressure ring, 3 rubber sealing ring, 4 sample, 5 conductive pad, 6 stainless steel shielding frame, 7 insulating plastic outer frame, 8 conductive bolt, 9 insulating sheath, 10 connecting power supply line.

Detailed ways

A device for unidirectional surface modification by micro-arc oxidation of metals and a method of use of the present invention will be further described in conjunction with the accompanying drawings and specific embodiments.

The structure of the sectional view of the unidirectional surface modification device for metal micro-arc oxidation is shown in Fig. 1 .

Definition: the distance from the bottom of the stainless steel shielding frame 6 on the projection diagram to the plane where the top of the insulating plastic frame 7 is located is L, and the distance from the bottom of the stainless steel shielding frame 6 on the projection diagram to the plane where the top of the stainless steel shielding frame 6 is located is P ;

Define the height of the conductive pad as H; said H is less than P, and P is less than L; define the height of the protruding part of a single rubber sealing ring as E, and the total height of the inverted "convex" type as F; then E+P=L ; Define the length of a single "step" as M, the total height as Q, the length of the step surface as R, the height of the first step as S, the height of the second step as T, and the length of the second step as U, then S+T=Q , R+U=M; Define the width of the insulating plastic outer frame 7 top as V, define the edge of a single "convex" type as W, then U+W=V; define the length of a single "convex" type bottom as X, Then X=R. See Figure 2 and Figure 3 for details.

In this embodiment, n is selected as 6.

On the projection diagram of the device used for metal micro-arc oxidation unidirectional surface modification designed in this embodiment, the width of a single "convex" top is defined as Y, which is consistent with the width of the top of the stainless steel shielding frame 6 .

In the projected view of the device designed in this embodiment for the unidirectional surface modification of metal by micro-arc oxidation, the height E of the "convex" type protruding part is equal to L-P.

A device for micro-arc oxidation unidirectional surface modification, the device consists of fastening bolt 1, insulating pressure ring 2, rubber sealing ring 3, sample 4, conductive pad 5, stainless steel shielding frame 6, insulating plastic outer Frame 7, conductive bolt 8 and its insulating sheath 9, and anode line 10 connected to the micro-arc oxidation power supply. The fastening bolt 1 is a bolt with an M8 specification and a diameter of 8 mm, and the conductive bolt 8 is a bolt with a diameter of M10 and a diameter of 10 mm. The outer diameter of the insulating pressure ring 2 is 210 mm, and the inner diameter is 150 mm. Four uniform and symmetrical bolt holes with a diameter of 9 mm are drilled on the insulating pressure ring 2 . The outer diameter of the insulating plastic outer frame 7 is 210 mm, and the inner diameter is 170 mm. M8 standard threaded holes are drilled at positions corresponding to the bolt through holes on the insulating pressure ring 2, and 11 mm bolt through holes are drilled at the center of the bottom. The stainless steel shielding frame 6 has an outer diameter of 170mm and an inner diameter of 160mm, and an M10 threaded hole is drilled at the center of the bottom. The rubber sealing ring 3 has an outer diameter of 180mm and an inner diameter of 150mm.

The sample 4 is placed on the conductive pad 5, and the rubber sealing ring 3 is put on the edge of the stainless steel shielding frame 6 and the sample 4; the insulating pressure ring 2 and the insulating plastic outer frame 7 are connected by four fastening bolts 1 Connect, fasten.

The anode line 10 of the micro-arc oxidation power supply is connected to the conductive bolt 8 .

2. A method for using a device for one-way surface modification of metal micro-arc oxidation, comprising the following steps:

Step 1: After the overall device is equipped, place the sample 4 on the conductive pad 5, and then put the rubber sealing ring 3 on the edge of the stainless steel shielding frame 6 and the sample 4.

Step 2: align the bolt through hole on the insulating pressure ring 3 with the threaded hole of the insulating plastic frame 7, and tighten the fastening bolt 1 so that the sealing rubber ring 3 is in close contact with the sample 4.

Step 3: According to the thickness of the sample, the conductive pads 5 of different thicknesses can be replaced to meet the experimental requirements.

Step 4: Connect the anode line 10 of the micro-arc oxidation power supply at the conductive bolt 8 .

Step 5: Place the device with the sample installed in the electrolytic cell, so that the surface of the sample is completely placed in the electrolyte, and adjust the appropriate depth to keep the sample parallel to the surface of the electrolyte.

Step 6: According to the pre-selected parameters, set the experimental parameters and experimental conditions, and turn on the power for micro-arc oxidation treatment.

Application example

Micro-arc oxidation treatment of 2A12 aluminum alloy:

In this example, the sample is a 2A12 circular plate with a diameter of φ=155mm and a thickness of h=4mm. The sample is placed on a conductive pad, and then a rubber sealing ring is placed on the stainless steel shielding frame and the edge of the sample, and the insulating pressure ring Align the upper bolt through hole with the threaded hole of the insulating plastic frame, and tighten the fastening bolt so that the sealing rubber ring is in close contact with the sample. Place the device with the sample installed in the electrolytic cell, so that the surface of the sample is completely placed in the electrolyte and kept parallel to the surface of the electrolyte, the anode line is connected to the micro-arc oxidation anode, and the power is turned on. In this example, the electrolyte solution uses Na ₂ SiO ₃ +KOH solution system, the concentration of which is Na ₂ SiO ₃ : 20g/L and KOH: 4g/L. The process parameters of micro-arc oxidation are: constant current mode, current density 20A/dm ² , frequency 500Hz, duty cycle 15% and time 30min. During the micro-arc oxidation process, the current is stable and the spark is uniform. After the micro-arc oxidation surface modification was completed, the sample was taken out, and it was observed that the surface of the sample contacted with the solution formed a film with uniform thickness and compactness, and there was no change on the reverse side. The unidirectional surface modification of the micro-arc oxidation was successfully achieved.

Claims (6)

1. A device for modifying a metal micro-arc oxidation unidirectional surface, which is characterized in that: the device is formed by assembling n fastening bolts (1), n insulating pressing rings (2), n rubber sealing rings (3), a sample (4), a conductive cushion block (5), a stainless steel shielding frame (6), an insulating plastic outer frame (7), conductive bolts (8), a conductive bolt insulating sheath (9) and an anode circuit (10) connected with a micro-arc oxidation power supply;

after assembly, any one of the n fastening bolts (1) penetrates through the corresponding insulating pressing ring and extends into the insulating outer frame (7), and the stainless steel shielding frame (6) is positioned in a space formed by the conductive cushion block and the insulating plastic outer frame (7) and is in close contact with the conductive cushion block and the insulating plastic outer frame (7);

after assembly, the conductive bolt is coated with an insulating sheath (9); the bottom of the insulating plastic outer frame (7) and the stainless steel shielding frame (6) are penetrated through and embedded into the reserved holes of the conductive cushion block (5); the conductive bolt is also connected with an anode circuit (10) connected with a micro-arc oxidation power supply;

after assembly, cutting the device along the surface A to obtain a section B, wherein the surface A is perpendicular to the bottom surface of the insulating plastic outer frame (7) and passes through 2 insulating pressing rings; projecting along the direction vertical to the section B to obtain a projection diagram, wherein on the projection diagram, a single insulating pressing ring is in a step shape, and a single rubber sealing ring is in an inverted convex shape;

definition: the distance from the bottom of the stainless steel shielding frame (6) to the plane of the top of the insulating plastic outer frame (7) on the projection view is L, and the distance from the bottom of the stainless steel shielding frame (6) to the plane of the top of the stainless steel shielding frame (6) on the projection view is P; defining the height of the conductive cushion block as H; the H is less than P, and P is less than L; defining the height of the protruding part of the single rubber sealing ring as E and the total height of the inverted convex part as F; e+p=l; defining the length of a single insulating pressing ring 'step' as M, the total height as Q, the length of a step surface as R, the first step height S, the second step height as T and the length of the second step as U, and then S+T= Q, R +U=M; the width of the top of the insulating plastic outer frame (7) is defined as V, the width of the table edge of the single rubber sealing ring 'convex' is defined as W, and then U+W=V; defining the length of the "convex" bottom of a single rubber seal as X, then x=r.

2. A device for unidirectional surface modification of metal micro-arc oxidation according to claim 1, wherein: after assembly, the sample (4) is fixed by a conductive cushion block (5) and a rubber sealing ring.

3. A device for unidirectional surface modification of metal micro-arc oxidation according to claim 1, wherein: and n is any integer from 3 to 8.

4. A device for unidirectional surface modification of metal micro-arc oxidation according to claim 1, wherein: and n is 6 or 4.

5. A device for unidirectional surface modification of metal micro-arc oxidation according to claim 1, wherein: on the projection, the width of the top of the single rubber sealing ring 'convex' is defined as Y, and the width of the single rubber sealing ring is consistent with the width of the top of the stainless steel shielding frame (6).

6. A device for unidirectional surface modification of metal micro-arc oxidation according to claim 1, wherein:

the fastening bolt is an M8-specification bolt with the diameter of 8mm, and the conductive bolt is an M10-specification bolt with the diameter of 10 mm;

the outer diameter of the insulating pressing ring is 210mm, the inner diameter of the insulating pressing ring is 150mm, and four uniformly symmetrical bolt through holes with the diameter of 9mm are drilled on the insulating pressing ring;

the outer diameter of the insulating plastic outer frame is 210mm, the inner diameter of the insulating plastic outer frame is 170mm, M8-specification threaded holes are drilled at positions corresponding to the bolt through holes on the insulating pressing ring, and 11-mm bolt through holes are drilled at the center of the bottom of the insulating plastic outer frame;

the outer diameter of the stainless steel shielding frame is 170mm, the inner diameter of the stainless steel shielding frame is 160mm, and a M10 specification threaded hole is drilled in the center of the bottom; the outer diameter of the rubber sealing ring is 180mm, and the inner diameter of the rubber sealing ring is 150mm.

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