1. A metal alloy surface micro-arc cleaning method is characterized by comprising the following steps: the metal alloy is placed in a water solution and communicated to form a conductive loop, high voltage is applied between the metal alloy and a counter electrode, plasma micro-arcs are formed on the surface of the metal alloy, and organic pollutants, a metal coating and old oxide scales on the surface of the metal alloy are removed and stripped by utilizing the high-temperature high-pressure effect of the plasma micro-arcs.

2. The metal alloy surface micro-arc cleaning method according to claim 1, comprising the steps of:

(1) clamping the metal alloy to be cleaned on a proper clamp, connecting a positive pole of a power supply through a lead to use the metal alloy as an anode, and connecting a stainless steel plate to a negative pole of the power supply through a lead to use the stainless steel plate as a cathode;

(2) respectively placing the metal alloy anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution to ensure that the metal alloy to be cleaned is completely immersed below the liquid level;

(3) setting the output voltage, frequency and duty ratio of a power supply, communicating a conductive loop and carrying out micro-arc cleaning treatment;

(4) and taking out the metal alloy anode after the micro-arc cleaning treatment, and washing the metal alloy anode with clear water.

3. The method for micro-arc cleaning of a metal alloy surface according to claim 2, wherein the aqueous solution comprises one or more of sodium hydroxide, sodium silicate and sodium dodecylbenzenesulfonate.

4. The method for cleaning the micro-arc on the surface of the metal alloy according to claim 3, wherein the concentration of the sodium hydroxide is 0 to 10g/L, the concentration of the sodium silicate is 0 to 8g/L, and the concentration of the sodium dodecyl benzene sulfonate is 0 to 2 g/L.

5. The method for micro-arc cleaning of a metal alloy surface according to claim 2, wherein the fixture is made of a material selected from the group consisting of aluminum and aluminum alloys, magnesium and magnesium alloys, and titanium alloys.

6. The method according to claim 2, wherein the total surface area of the cathode of the stainless steel plate is not less than one third of the total surface area of the anode of the metal alloy.

7. The metal alloy surface micro-arc cleaning method according to claim 2, wherein the output voltage in the step (3) is 400V to 800V, the frequency is 100Hz to 800Hz, and the duty ratio is 20% to 60%.

8. The metal alloy surface micro-arc cleaning method according to claim 2, wherein the treatment time of the micro-arc cleaning treatment in the step (3) is 30s to 20 min.

9. The method for micro-arc cleaning the surface of the metal alloy according to claim 2, wherein the temperature of the aqueous solution during the micro-arc cleaning treatment in the step (3) is 20 to 60 ℃.

10. Use of a method according to any of claims 1-9 for micro-arc cleaning of a metal alloy surface in the fields of degreasing, paint removal, glue removal, descaling, rust removal, surface cleaning, and surface activation.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

Metal sheets and profiles are widely used in various industries, and these metal products inevitably suffer from contamination and oxidation, especially oil stain, oxide scale and paint film, in the processing environment and in the transportation process during the processes of forming, temporary storage, transferring, recycling and reusing, which are very disadvantageous for the subsequent treatment of the metal products, and must be removed by a proper cleaning and decontamination process to obtain a clean surface.

Solvent cleaning is the most common method, which mainly adopts organic solvents such as benzene, acetone, ethanol and the like to scrub or ultrasonically clean, the method is simple to implement, but is easy to cause incomplete cleaning, so that the subsequent coating and plating have defects, and the method is not environment-friendly and causes great threat to the health and ecological environment of operators.

In addition, several patents report novel cleaning methods, laser cleaning and plasma cleaning. Laser cleaning is mainly to evaporate or sublimate the contaminants on the surface of the object to be cleaned by using the thermal effect of the focused laser beam. The laser cleaning process does not need chemical reagents basically, but the laser device is large in investment, and the most important point is that for parts with complex solid geometry, due to the linear transmission effect of laser beams and the mutual shielding effect of a plurality of groove holes of the parts, the laser cleaning process cannot clean all outer surfaces thoroughly.

The cleaning principle of plasma cleaning is to put the workpiece to be cleaned in a vacuum environment, fill in process gas, vibrate the process gas into ions with certain reaction activity or high energy by using a high-voltage alternating electric field generated by a radio frequency source, the ions react or collide with organic pollutants or microparticle pollutants on the surface of the workpiece to form volatile substances, and then remove the volatile substances by using working gas and a vacuum pump, thereby achieving the purpose of cleaning and activating the surface. The plasma cleaning firstly needs to realize a vacuum environment, process gas needs to be reasonably selected, and the state of an electric field of a radio frequency source is adjusted, so that the plasma cleaning device is complex and unstable in process, and the efficiency of cleaning workpieces on a large scale is low.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a metal alloy surface micro-arc cleaning method and application, and the method can solve the defects of environmental pollution, large investment, incomplete cleaning, complex equipment and process and low cleaning efficiency in the traditional cleaning method; the metal alloy surface micro-arc cleaning method provided by the invention has the advantages of short process flow, stable control and simple requirements on equipment and construction conditions; the shape of the workpiece is not required, the phenomenon of shielding the workpiece when the workpiece is cleaned, such as bending of a hole groove, and the like, is avoided, and dead-angle-free cleaning can be achieved; the paint has the advantages of environmental protection, strong universality and wide application range, can effectively remove oil stains, paint layers, glue layers, oxide skins and rust layers on the surface of the metal alloy, and achieves the purposes of surface cleaning and surface activation.

In order to achieve the above object, the technical solution of the present invention is as follows:

in a first aspect of the present invention, a method for cleaning a micro-arc of a metal alloy surface is provided, which comprises the steps of: the metal alloy is placed in a water solution and communicated to form a conductive loop, high voltage is applied between the metal alloy and a counter electrode, plasma micro-arcs are formed on the surface of the metal alloy, and organic pollutants, a metal coating and old oxide scales on the surface of the metal alloy are removed and stripped by utilizing the high-temperature high-pressure effect of the plasma micro-arcs.

Specifically, the metal alloy surface micro-arc cleaning method specifically comprises the following steps:

(1) clamping the metal alloy to be cleaned on a proper clamp, connecting a positive pole of a power supply through a lead to use the metal alloy as an anode, and connecting a stainless steel plate to a negative pole of the power supply through a lead to use the stainless steel plate as a cathode;

(2) respectively placing the metal alloy anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution to ensure that the metal alloy to be cleaned is completely immersed below the liquid level;

(3) setting the output voltage, frequency and duty ratio of a power supply, communicating a conductive loop and carrying out micro-arc cleaning treatment;

(4) and taking out the metal alloy anode after the micro-arc cleaning treatment, and washing the metal alloy anode with clear water.

In a second aspect of the invention, the invention provides an application of the micro-arc cleaning method for the metal alloy surface in the fields of degreasing, paint removing, glue removing, scale removing, rust removing, surface cleaning and surface activation.

The specific embodiment of the invention has the following beneficial effects:

(1) the metal alloy surface micro-arc cleaning method provided by the invention has the advantages of clear cleaning principle, short process flow and stable control; the requirements on equipment and construction conditions are simple; particularly, the cleaning machine has no requirement on the shape of a workpiece, does not have the shielding phenomenon of bending of a hole groove and the like when the workpiece is cleaned, and can achieve cleaning without dead angles.

(2) The method for cleaning the micro-arc on the surface of the metal alloy is green and environment-friendly, does not involve the use and discharge of toxic and harmful substances such as acid mist, heavy metal ions, organic solvents, smoke dust and the like in the whole process, and is very friendly to the health of people and the ecological environment.

(3) The metal alloy surface micro-arc cleaning method provided by the invention has strong universality and wide application range, and can effectively remove oil stains, paint layers, adhesive layers, oxide skins and rust layers on the metal alloy surface, thereby achieving the purposes of surface cleaning and surface activation.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a diagram illustrating the effect of the cleaning process of the organic electrophoretic coating on the surface of the workpiece in example 1 of the present invention.

FIG. 2 is a graph showing the effect of the cleaning process of the inorganic phosphate coating on the workpiece surface in example 2 of the present invention.

FIG. 3 is a diagram illustrating the effect of the cleaning process of the copper plating layer on the workpiece surface in example 3 of the present invention.

Fig. 4 is a diagram showing the effects of cleaning and removing oil stains and scale on the workpiece surface in example 4 of the present invention.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In one embodiment of the present invention, a method for cleaning a micro-arc on a metal alloy surface is provided, the method comprising the steps of: the metal alloy is placed in a water solution and communicated to form a conductive loop, high voltage is applied between the metal alloy and a counter electrode, plasma micro-arcs are formed on the surface of the metal alloy, and organic pollutants, a metal coating and old oxide scales on the surface of the metal alloy are removed and stripped by utilizing the high-temperature high-pressure effect of the plasma micro-arcs.

Specifically, the metal alloy surface micro-arc cleaning method specifically comprises the following steps:

(1) clamping the metal alloy to be cleaned on a proper clamp, connecting a positive pole of a power supply through a lead to use the metal alloy as an anode, and connecting a stainless steel plate to a negative pole of the power supply through a lead to use the stainless steel plate as a cathode;

(2) respectively placing the metal alloy anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution to ensure that the metal alloy to be cleaned is completely immersed below the liquid level;

(3) setting the output voltage, frequency and duty ratio of a power supply, communicating a conductive loop and carrying out micro-arc cleaning treatment;

(4) and taking out the metal alloy anode after the micro-arc cleaning treatment, and washing the metal alloy anode with clear water.

The metal alloy surface micro-arc cleaning method has clear cleaning principle, short process flow and stable control, has no requirement on the shape of the workpiece, does not have the shielding phenomenon of bending of a hole groove and the like when the workpiece is cleaned, and can achieve the purpose of cleaning without dead angles.

In one or more embodiments, the aqueous solution comprises one or more of sodium hydroxide, sodium silicate, and sodium dodecylbenzene sulfonate;

further, the concentration of sodium hydroxide is 0-10 g/L, the concentration of sodium silicate is 0-8 g/L, and the concentration of sodium dodecyl benzene sulfonate is 0-2 g/L;

the sodium hydroxide is used for adjusting the conductivity and the pH value of the aqueous solution, the sodium silicate is used for inducing the generation of plasma micro-arcs, and the sodium dodecyl benzene sulfonate is used for activating organic substances on the surface of a workpiece. The micro-arc cleaning method for the surface of the metal alloy does not adopt and generate toxic and harmful substances such as acid mist, heavy metal ions, organic solvents, smoke dust and the like, and is very friendly to the health of people and the ecological environment.

In one or more embodiments, the material of the clamp is aluminum and aluminum alloy, magnesium and magnesium alloy, titanium and titanium alloy.

In one or more embodiments, the total surface area of the stainless steel plate cathode is no less than one third of the total surface area of the metal alloy anode.

In one or more embodiments, the output voltage in the step (3) is 400V to 800V, the frequency is 100Hz to 800Hz, and the duty ratio is 20% to 60%. Under the voltage and frequency conditions, the plasma micro-arc formed on the surface of the metal alloy has the best high-temperature and high-pressure effect, and organic pollutants, a metal coating and old oxide scales on the surface of the metal alloy can be better removed and stripped.

In one or more embodiments, the treatment time of the micro-arc cleaning treatment in the step (3) is 30s to 20 min; the cleaning method of the invention has the advantages of high cleaning speed and high efficiency.

In one or more embodiments, the temperature of the aqueous solution during the micro-arc cleaning treatment in the step (3) is 20-60 ℃.

In an embodiment of the invention, the application of the micro-arc cleaning method for the surface of the metal alloy in the fields of degreasing, paint removing, glue removing, descaling, rust removing, surface cleaning and surface activation is provided.

The metal alloy surface micro-arc cleaning method has strong universality and wide application range, can effectively remove oil stains, paint layers, adhesive layers, oxide skins and rust layers on the surface of the metal alloy, and achieves the purposes of surface cleaning and surface activation.

The invention will be further explained and illustrated with reference to specific examples.

Example 1

Cleaning an organic electrophoretic coating on the surface of a workpiece:

firstly, clamping a magnesium alloy workpiece with an organic electrophoretic coating on the surface on a clamp made of pure aluminum, connecting a positive electrode of a power supply through a lead to use the magnesium alloy workpiece as an anode, and connecting a stainless steel plate to a negative electrode of the power supply through a lead to use the stainless steel plate as a cathode, wherein the total surface area of the cathode is about 3 times of that of the anode;

then, respectively placing the workpiece anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution, so that the metal alloy to be cleaned is completely immersed below the liquid level, wherein the aqueous solution comprises 5g/L of sodium hydroxide, 5g/L of sodium silicate, 0.2g/L of sodium dodecyl benzene sulfonate and deionized water as a solvent;

then setting the output voltage of a power supply to be 500V, the frequency to be 500Hz and the duty ratio to be 30%, communicating a conductive loop, and performing micro-arc cleaning treatment, wherein the duration time of the micro-arc cleaning treatment is 6min, and the temperature of an aqueous solution is kept to be 30 ℃ in the cleaning process;

after the micro-arc cleaning treatment is finished, taking out the workpiece, and washing the workpiece with clear water; removing the clamp after drying;

FIG. 1 records the cleaning state of the organic electrophoretic coating on the surface of the workpiece before and after the workpiece is subjected to micro-arc cleaning and during the cleaning process, wherein the surface of the workpiece is completely covered by the black electrophoretic coating before the micro-arc cleaning, and the electrophoretic coating is gradually cleaned from the edge to the center in the cleaning process until the electrophoretic coating is completely removed finally.

Example 2

Cleaning an inorganic phosphating coating on the surface of a workpiece:

firstly, clamping a magnesium alloy workpiece with an inorganic phosphating coating on the surface on a clamp made of pure aluminum, connecting a positive electrode of a power supply through a lead to use the magnesium alloy workpiece as an anode, and connecting a stainless steel plate to a negative electrode of the power supply through a lead to use the stainless steel plate as a cathode; wherein the total surface area of the cathode is about 2 times the total surface area of the anode;

then, respectively placing the workpiece anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution to ensure that the metal alloy to be cleaned is completely immersed below the liquid level; the composition of the aqueous solution is 7g/L sodium hydroxide and 3g/L sodium silicate, and the solvent is deionized water;

then setting the output voltage of a power supply to be 650V, the frequency to be 400Hz and the duty ratio to be 40%, communicating a conductive loop, and performing micro-arc cleaning treatment, wherein the duration time of the micro-arc cleaning treatment is 15min, and the temperature of an aqueous solution is kept to be 40 ℃ in the cleaning process;

after the micro-arc cleaning treatment is finished, taking out the workpiece, and washing the workpiece with clear water; and removing the clamp after drying.

FIG. 2 records the cleaning state of the inorganic phosphate coating on the surface of the workpiece before and after the workpiece is subjected to micro-arc cleaning and during the cleaning process, wherein the surface of the workpiece is completely covered by the black phosphate coating before the micro-arc cleaning, and the weak part of the phosphate coating is firstly subjected to micro-arc breakdown and cleaned off during the cleaning process, and then is gradually cleaned off by outward diffusion from the position until the weak part is completely removed.

Example 3

Cleaning a copper plating layer on the surface of a workpiece:

firstly, clamping an aluminum alloy workpiece with a copper-plated layer on the surface on a clamp made of pure aluminum, connecting a positive electrode of a power supply through a lead to use the aluminum alloy workpiece as an anode, and connecting a stainless steel plate to a negative electrode of the power supply through a lead to use the stainless steel plate as a cathode; wherein the total surface area of the cathode is about 8 times the total surface area of the anode;

then, respectively placing the workpiece anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution, so that the metal alloy to be cleaned is completely immersed below the liquid level, wherein the aqueous solution comprises 5g/L of sodium hydroxide, 8g/L of sodium silicate and deionized water as a solvent;

then setting the output voltage of a power supply to be 400V, the frequency to be 600Hz and the duty ratio to be 20%, communicating a conductive loop, and performing micro-arc cleaning treatment, wherein the duration time of the micro-arc cleaning treatment is 4min, and the temperature of an aqueous solution is kept to be 30 ℃ in the cleaning process;

after the micro-arc cleaning treatment is finished, taking out the workpiece, and washing the workpiece with clear water; and removing the clamp after drying.

FIG. 3 records the cleaning state of the copper plating layer on the surface of the workpiece before and after the workpiece is subjected to micro-arc cleaning and in the cleaning process, wherein the surface of the workpiece is completely covered by the red-orange copper plating layer before the micro-arc cleaning, and the copper plating layer is uniformly burned by the high-temperature and high-pressure plasma micro-arc in the cleaning process until the copper plating layer is completely removed finally.

Example 4

Cleaning oil stains and oxide scales on the surface of the workpiece:

firstly, clamping a magnesium alloy workpiece with greasy dirt and oxide skin on the surface on a clamp made of pure aluminum, connecting a positive electrode of a power supply through a lead to use the workpiece as an anode, and connecting a stainless steel plate to a negative electrode of the power supply through a lead to use the workpiece as a cathode; wherein the total surface area of the cathode is about 2 times the total surface area of the anode;

then, respectively placing the workpiece anode and the stainless steel plate cathode in an insulating tank filled with aqueous solution, so that the metal alloy to be cleaned is completely immersed below the liquid level, wherein the aqueous solution comprises 3g/L of sodium hydroxide, 3g/L of sodium silicate, 0.1g/L of sodium dodecyl benzene sulfonate, and the solvent is deionized water.

Then setting the output voltage of a power supply to be 400V, the frequency to be 500Hz and the duty ratio to be 30%, communicating a conductive loop, and performing micro-arc cleaning treatment, wherein the duration time of the micro-arc cleaning treatment is 1min, and the temperature of an aqueous solution is kept to be 30 ℃ in the cleaning process;

after the micro-arc cleaning treatment is finished, taking out the workpiece, and washing the workpiece with clear water; and removing the clamp after drying.

Fig. 4 records the cleaning state of the oil stain and the oxide skin on the surface of the workpiece before and after the workpiece is subjected to micro-arc cleaning, the surface of the workpiece is stained and stained by the oil stain and the oxide skin before micro-arc cleaning, the initial oil stain and the oxide skin are completely removed after micro-arc cleaning, the surface of the workpiece is in a fresh and clean state, and the micro-arc cleaning effect is excellent.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.