Application of ionic liquids in electrolytic polishing of metal solids

Abstract

The invention discloses the application of ionic liquid in metal solid electrolytic polishing. The invention adopts ionic liquid for metal solid electrolytic polishing, which has the characteristics of low carbon, environmental protection and high efficiency, and can achieve fast and good polishing effect. In particular, for high-strength and corrosion-resistant metal materials such as titanium alloy, nickel alloy, tungsten alloy, copper alloy, aluminum alloy, magnesium alloy or steel, the ionic liquid is used for metal electrolytic polishing treatment, and excellent polishing effect is achieved, which has wide application and great application value.

Description

Technical Field

[0001] The invention relates to the technical field of metal surface treatment, in particular to the application of ionic liquid in metal solid electrolytic polishing. Background Art

[0002] With the development of society, metals with shiny surfaces are gaining more and more attention. In addition to improving the appearance, shiny metals can also reduce friction, improve mechanical precision, improve cutting performance, and extend service life. In the precision manufacturing and high-end consumer goods industries, there are strict requirements for the brightness of metal surfaces. Titanium alloys, nickel alloys, tungsten alloys, copper alloys, aluminum alloys, magnesium alloys, steel and other materials have excellent corrosion resistance and high strength and toughness. Only through multi-step manual polishing can a smooth surface be achieved. General chemical polishing and electrochemical polishing processes do not work. The high strength of the material will also greatly increase the difficulty of manual polishing, the construction period is long, it is difficult to obtain a unified standard and a low defective rate, and it is difficult to achieve a high leveling effect on corners, gaps and other parts.

[0003] How to find a polishing medium suitable for metal polishing, especially metal solid electrolytic polishing, has become a technical problem that urgently needs to be solved. Summary of the invention

[0004] The present invention aims to solve at least one of the above-mentioned technical problems existing in the prior art. To this end, one of the purposes of the present invention is to provide an application of ionic liquid in metal solid electropolishing, a second purpose of the present invention is to provide a polishing medium for metal solid electropolishing containing ionic liquid, and a third purpose of the present invention is to provide a method for metal solid electropolishing using ionic liquid.

[0005] The inventors have found through experimental research that the application of ionic liquids in metal solid electrolytic polishing has a good polishing effect and has the advantages of being low carbon, environmentally friendly, fast and efficient.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A first aspect of the present invention provides the use of ionic liquid in electrolytic polishing of metal solids.

[0008] Preferably, the ionic liquid is used as an electrolyte and / or solvent in the electrolytic polishing of metal solids; further preferably, the ionic liquid is used as an electrolyte, a solvent, or as both an electrolyte and a solvent in the electrolytic polishing of metal solids.

[0009] Preferably, the resistivity of the ionic liquid is ≤5×10 5 Ω / cm; further preferably, the resistivity of the ionic liquid is ≤1×10 5 Ω / cm.

[0010] Preferably, the ionic liquid includes at least one of imidazole ionic liquids, quaternary ammonium salt ionic liquids, quaternary phosphonium salt ionic liquids, pyrrole ionic liquids, and piperidine ionic liquids.

[0011] Preferably, the ionic liquid is a halogenated ionic liquid, that is, an ionic liquid containing halogen; more preferably, the ionic liquid is at least one of a chloride ionic liquid and a bromide ionic liquid.

[0012] Preferably, the ionic liquid includes at least one of 1-ethyl-3-methylimidazole ethyl sulfate, 1-ethyl-3-methylimidazole dimethyl phosphate, 1-ethyl-3-methylimidazole diethyl phosphate, 1-butyl-3-methylimidazole dibutyl phosphate, 1-ethyl-3-methylimidazole acetate, 1-butyl-3-methylimidazole acetate, 1-butyl-3-methylimidazole bromide, 1-ethyl-3-methylimidazole bromide, 1-ethyl-3-methylimidazole chloride, and 1-butyl-3-methylimidazole chloride.

[0013] Preferably, the metal includes at least one of titanium alloy, nickel alloy, tungsten alloy, copper alloy, aluminum alloy, magnesium alloy and steel.

[0014] The second aspect of the present invention provides a polishing medium for metal solid electrolytic polishing, comprising solid particles containing ionic liquid; the ionic liquid is the ionic liquid in the application described in the first aspect of the present invention.

[0015] Preferably, the ionic liquid is located inside the solid particles, or inside and on the surface of the solid particles. The ionic liquid can adjust the conductivity and ion exchange rate of the solid particles, and can play the role of conducting electricity and transporting ions.

[0016] Preferably, in the polishing medium, the mass ratio of the solid particles to the ionic liquid is 100:(0.1~100); further preferably, the mass ratio of the solid particles to the ionic liquid is 100:(1~100); further preferably, the mass ratio of the solid particles to the ionic liquid is 100:(1~50); further preferably, the mass ratio of the solid particles to the ionic liquid is 100:(10~50).

[0017] Preferably, in the polishing medium, the solid particles have a porous structure and groups that adsorb and complex metal ions.

[0018] Furthermore, in the polishing medium, the solid particles have a porous structure, are hydrophilic and have a certain hardness, will not break easily when slightly colliding with metal, can absorb a certain amount of solution and have conductivity and ion exchange properties, and may not have conductivity itself. The solid particles have groups that can adsorb and complex metal ions, thereby playing a role in fixing metal ions, reducing the concentration of metal ions in the electrolyte, reducing overpotential, and promoting the oxidation process on the metal surface.

[0019] Preferably, the groups in the solid particles that adsorb and complex metal ions include at least one of carboxyl groups, amine groups, and hydroxyl groups.

[0020] Preferably, in the polishing medium, the solid particles include one or more of ion exchange resin, silica gel, and molecular sieve.

[0021] Further preferably, the solid particles include an acrylic acid type ion exchange resin containing at least one of a carboxyl group, a hydroxyl group, and an amine group. The acrylic acid type ion exchange resin containing at least one of a carboxyl group, a hydroxyl group, and an amine group can be prepared by polymerizing a monomer containing a carboxyl group, a hydroxyl group, or an amine group with an acrylic acid (ester) monomer, etc., which is a conventional method in the art, such as the contents disclosed in CN114908409A, CN114908410A, and CN115029768A, or directly purchasing a commercially available product.

[0022] Preferably, the solid particles contain COOH / COO - Carboxylic acid type acrylic ion exchange resin.

[0023] Preferably, the solid particulate matter is a carboxylic acid type acrylic acid ion exchange resin with a pH value of 5≤<7.

[0024] Preferably, the polishing medium further contains at least one of salt, brightener and solvent.

[0025] Preferably, the salt includes at least one of sulfate, chloride, zinc, sodium, potassium, and ammonium salts; further preferably, the salt includes at least one of sodium sulfate, potassium sulfate, zinc sulfate, ammonium sulfate, sodium chloride, potassium chloride, zinc chloride, ammonium chloride, sodium fluoride, sodium nitrate, sodium phosphate, and disodium edetate.

[0026] Preferably, the brightener includes at least one of glucose, saccharin, starch, sucrose and benzotriazole.

[0027] Preferably, the solvent includes at least one of water, small molecule alcohol, small molecule ketone, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), and dioxane. Further preferably, the small molecule alcohol includes at least one of methanol, ethanol, n-propanol, isopropanol, butanol, and butanediol; the small molecule ketone includes at least one of acetone, butanone, and cyclohexanone.

[0028] Preferably, in the polishing medium, the mass ratio of the solid particles to the salt is 100:(0.1-30); further preferably, the mass ratio of the solid particles to the salt is 100:(0.1-15); further preferably, the mass ratio of the solid particles to the salt is 100:(0.5-10); further preferably, the mass ratio of the solid particles to the salt is 100:(0.8-5).

[0029] Preferably, in the polishing medium, the mass ratio of the solid particles to the brightener is 100:(0.01-20); further preferably, the mass ratio of the solid particles to the brightener is 100:(0.1-15); further preferably, the mass ratio of the solid particles to the brightener is 100:(0.5-10); further preferably, the mass ratio of the solid particles to the brightener is 100:(0.8-5).

[0030] Preferably, in the polishing medium, the mass ratio of the solid particles to the solvent is 100:(0.001-100); further preferably, the mass ratio of the solid particles to the solvent is 100:(0.01-50); further preferably, the mass ratio of the solid particles to the solvent is 100:(0.1-30); further preferably, the mass ratio of the solid particles to the solvent is 100:(1-20).

[0031] It should be noted that electropolishing is to immerse the metal in a special chemical solution composed of various components, relying on high electrochemical potential to oxidize the metal to obtain a smooth and bright surface. The chemical solution used in conventional electropolishing is a strong acid or a highly volatile liquid, which is not convenient for transportation and storage, and is harmful to workers. Waste liquid treatment is also a big problem. Solid electropolishing uses solid particles with ion adsorption / exchange / complexation capabilities and internal conductive solutions to replace the electrolyte. The solid particles are in contact with the metal parts to be polished, thereby achieving polishing of the surface of the metal parts. Although the solid particles are in contact with the metal parts to be polished, the relative movement rate of this contact is low, and the hardness of the solid particles is lower than that of the metal parts, so the physical mechanical polishing process can be ignored.

[0032] The third aspect of the present invention provides a method for solid electrolytic polishing of metal, which uses the polishing medium described in the second aspect of the present invention to perform solid electrolytic polishing on the metal.

[0033] Preferably, the method for solid metal electrolytic polishing comprises the following steps:

[0034] 1) placing a metal to be polished and the polishing medium for metal solid electrolytic polishing according to the second aspect of the present invention in an electrochemical polishing device; the metal to be polished is connected to the positive electrode of the power supply of the electrochemical polishing device, and the polishing medium for metal solid electrolytic polishing is connected to the negative electrode of the power supply of the electrochemical polishing device;

[0035] 2) The electrochemical polishing device is powered on for electrolytic polishing. During electrolytic polishing, the metal to be polished and the polishing medium of the metal solid electrolytic polishing undergo relative friction movement.

[0036] Preferably, the voltage of the electropolishing is 10V to 110V; further preferably, the voltage of the electropolishing is 30V to 100V; still further preferably, the voltage of the electropolishing is 45V to 90V; further preferably, the voltage of the electropolishing is 50V to 70V.

[0037] Preferably, the electrolytic polishing time is 5 min to 90 min; further preferably, the electrolytic polishing time is 10 min to 80 min; further preferably, the electrolytic polishing time is 30 min to 60 min.

[0038] Preferably, in the electrolytic polishing, the relative friction movement rate is 30 r / min to 120 r / min; further preferably, the relative friction movement rate is 50 r / min to 100 r / min; further preferably, the relative friction movement rate is 60 r / min to 90 r / min.

[0039] The beneficial effects of the present invention are:

[0040] The present invention uses ionic liquid for metal solid electrolytic polishing, which has the characteristics of low carbon, environmental protection and high efficiency, and can achieve fast and good polishing effect. In particular, for high-strength and corrosion-resistant metal materials such as titanium alloy, nickel alloy, tungsten alloy, copper alloy, aluminum alloy, magnesium alloy or steel, the ionic liquid is used for metal electrolytic polishing treatment, and excellent polishing effect is achieved, which has wide application and great application value.

[0041] Specifically, ionic liquids have a high electrical conductivity because they are composed entirely of anions and cations, and can simultaneously function as conductors and ion transporters. In addition, ionic liquids are in a liquid state and have a low viscosity, and can function as solvents. Therefore, ionic liquids can function as both solvents and electrolytes, and can be used alone or mixed with other solvents and electrolytes. At the same time, ionic liquids do not contain water, so they will not form oxides or hydroxides after metal electrolysis, thereby protecting the smooth surface. For metals that can oxidize and hydrolyze, such as magnesium, aluminum, copper, titanium, etc., the use of ionic liquids will have a better polishing effect than water systems. In addition, ionic liquids have a low vapor pressure, are difficult to volatilize, will not cause solvent volatilization pollution, and do not need to add new solvents during the long polishing process, which has good environmental protection and process reduction effects. Therefore, the application of ionic liquids in metal solid electrolytic polishing has broad market prospects. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below by specific examples. Unless otherwise specified, the raw materials, reagents or devices used in the examples and comparative examples can be obtained from conventional commercial sources or can be obtained by prior art methods. Unless otherwise specified, the experiments or test methods are conventional methods in the art.

[0043] The carboxylic acid type acrylic acid ion exchange resin used below is a COOH type acrylic acid ion exchange resin prepared by referring to the preparation method of polyacrylate porous resin microspheres with carboxyl groups disclosed in the specific embodiment of CN114908409A. The carboxylic acid type acrylic acid ion exchange resin used to prepare the solid particles in the examples and comparative examples all uses the same resin.

[0044] Among the ionic liquids used in the following examples, the resistivity of 1-ethyl-3-methylimidazolium ethyl sulfate is 7.4×10 4 Ω / cm, the resistivity of 1-ethyl-3-methylimidazole chloride is 8.1×10 4 Ω / cm.

[0045] Unless otherwise specified, the following "parts" refer to parts by mass.

[0046] The compositions of metal electrolytic polishing medium embodiments 1 to 4 are shown in Table 1.

[0047] Table 1 Composition of Metal Solid Electrolytic Polishing Media Examples 1 to 4

[0048]

[0049] Example 1

[0050] Referring to Table 1, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6 and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate.

[0051] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0052] The carboxylic acid type acrylic acid ion exchange resin is immersed in an aqueous solution of sodium hydroxide, and after the pH is stabilized to 6, it is dried at room temperature, and then washed with ethanol and dried at room temperature to obtain a carboxylic acid type acrylic acid ion exchange resin with a pH of 6.

[0053] 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6 and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate were mixed evenly to obtain solid particles for solid electrolytic polishing in this example.

[0054] Example 2

[0055] Referring to Table 1, the metal solid electrolytic polishing medium in this example is composed of 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6 and 1 part of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate. The difference between this example and Example 1 is only the amount of ionic liquid used, and the rest is the same as Example 1. Unless otherwise specified, the preparation method of carboxylic acid type acrylic acid ion exchange resin in the following examples or comparative examples is the same as the method for preparing carboxylic acid type acrylic acid ion exchange resin with pH=6 in Example 1.

[0056] Example 3

[0057] Referring to Table 1, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6 and 20 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate. The difference between this example and Example 1 is only the amount of ionic liquid used, and the rest is the same as Example 1.

[0058] Example 4

[0059] Referring to Table 1, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6 and 10 parts of ionic liquid 1-ethyl-3-methylimidazole chloride. The difference between this example and Example 1 is only the type of ionic liquid, and the rest is the same as Example 1.

[0060] The compositions of electrolytic polishing medium embodiments 5 to 8 are shown in Table 2.

[0061] Table 2 Composition of Metal Solid Electrolytic Polishing Media Examples 5 to 8

[0062]

[0063] Example 5

[0064] Referring to Table 2, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 3 parts of sodium sulfate.

[0065] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0066] 100 parts of carboxylic acid type acrylic acid ion exchange resin, 3 parts of sodium sulfate, and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate were mixed to obtain the metal solid electrolytic polishing medium of this example.

[0067] Example 6

[0068] Referring to Table 2, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 1 part of sodium sulfate. The difference between this example and Example 5 is only the amount of ionic liquid used, and the rest is the same as Example 5.

[0069] Example 7

[0070] Referring to Table 2, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 3 parts of sodium chloride.

[0071] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0072] 100 parts of carboxylic acid type acrylic acid ion exchange resin, 3 parts of sodium chloride, and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate were mixed to obtain the metal solid electrolytic polishing medium of this example.

[0073] Example 8

[0074] Referring to Table 2, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic acid ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 1 part of sodium chloride. The difference between this example and Example 7 is only the amount of ionic liquid used, and the rest is the same as Example 7.

[0075] The compositions of metal electrolytic polishing medium Examples 9 to 11 and Comparative Examples 1 to 3 are shown in Table 2.

[0076] Table 3 Composition of Metal Solid Electrolytic Polishing Media Examples 9 to 11 and Comparative Examples 1 to 3

[0077]

[0078] Example 9

[0079] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 10 parts of ethanol.

[0080] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0081] 100 parts of carboxylic acid type acrylic ion exchange resin, 10 parts of ethanol and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate were mixed to obtain the metal solid electrolytic polishing medium of this example.

[0082] Example 10

[0083] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate and 10 parts of DMF.

[0084] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0085] 100 parts of carboxylic acid type acrylic acid ion exchange resin, 10 parts of DMF and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate were mixed to obtain the metal solid electrolytic polishing medium of this example.

[0086] Embodiment 11

[0087] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate, 10 parts of ethanol and 3 parts of sodium chloride.

[0088] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0089] 100 parts of carboxylic acid type acrylic ion exchange resin are mixed with 3 parts of sodium chloride, 10 parts of ethanol, and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate to obtain the metal solid electrolytic polishing medium of this example.

[0090] Comparative Example 1

[0091] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6 and 10 parts of ethanol.

[0092] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0093] 100 parts of carboxylic acid type acrylic ion exchange resin were mixed with 10 parts of ethanol solution to obtain the metal solid electrolytic polishing medium of this example.

[0094] Comparative Example 2

[0095] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ethanol and 3 parts of sodium chloride.

[0096] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0097] 100 parts of carboxylic acid type acrylic ion exchange resin are mixed with 3 parts of sodium chloride and 10 parts of ethanol to obtain the metal solid electrolytic polishing medium of this example.

[0098] Comparative Example 3

[0099] Referring to Table 3, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6 and 10 parts of DMF.

[0100] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0101] 100 parts of carboxylic acid type acrylic ion exchange resin and 10 parts of DMF were mixed to obtain the metal solid electrolytic polishing medium of this example.

[0102] The composition of metal electrolytic polishing medium Example 12 is shown in Table 4.

[0103] Table 4 Composition of Metal Solid Electrolytic Polishing Medium Example 12

[0104]

[0105] Example 12

[0106] Referring to Table 4, the metal solid electrolytic polishing medium of this example is composed of 100 parts of carboxylic acid type acrylic ion exchange resin with pH=6, 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate, 3 parts of glucose and 3 parts of sodium chloride.

[0107] The preparation method of the metal solid electrolytic polishing medium in this example is as follows:

[0108] 100 parts of carboxylic acid type acrylic ion exchange resin are mixed with 3 parts of sodium chloride, 3 parts of glucose and 10 parts of ionic liquid 1-ethyl-3-methylimidazole ethyl sulfate to obtain the metal solid electrolytic polishing medium of this example.

[0109] Titanium alloy solid electrolytic polishing experiment

[0110] The solid electrolytic polishing application experiments of titanium alloy were carried out respectively using the metal solid electrolytic polishing medium Examples 1 to 12 and Comparative Examples 1 to 3 prepared above. The titanium alloys used in the application experiments were all the same, and their surface roughness before polishing was 5.64 μm. The surface roughness is the roughness test result of the surface of the titanium alloy part using an optical profilometer.

[0111] The method of solid electrolytic polishing of titanium alloy parts is as follows:

[0112] The titanium alloy piece was connected to the positive electrode of the power supply of the electrochemical polishing device, and the metal solid electrolytic polishing medium Examples 1 to 12 and Comparative Examples 1 to 3 were placed in metal net bags and connected to the negative electrode of the power supply of the electrochemical polishing device. The electrochemical polishing device was powered on for electrolytic polishing, and the titanium alloy piece to be polished and the metal electrolytic polishing medium underwent relative friction motion during electrolytic polishing. The applied voltage was 60V, the relative motion rate was 90r / min, and the polishing time was 60min.

[0113] The experimental results of metal solid electrolytic polishing of titanium alloys using metal solid electrolytic polishing medium Examples 1 to 12 and Comparative Examples 1 to 3 are shown in Table 5.

[0114] Table 5 Experimental results of solid electrolytic polishing of titanium alloy

[0115]

[0116]

[0117] According to the experimental results in Table 5:

[0118] 1. From the experimental results of Examples 1 to 4, it can be seen that the use of ionic liquid as electrolyte and solvent for metal solid electrolytic polishing has a good polishing effect, and the chlorine-containing ionic liquid has a better polishing effect.

[0119] 2. From the experimental results of Examples 5-8, it can be seen that adding inorganic salts on the basis of Example 1 can further improve the polishing effect. Among them, the effect of using chloride salts is better, because chloride salts can enhance the etching effect and enhance the conductivity, thereby achieving better polishing effect.

[0120] 3. From the experimental results of Examples 9-10, it can be seen that the polishing effect can be improved by adding organic solvents such as ethanol or DMF on the basis of Example 1. This is because the addition of organic solvents can reduce viscosity and accelerate ion exchange, thereby improving the polishing effect.

[0121] 4. It can be seen from the experimental results of Example 11 and Example 7 that adding small molecule alcohol to the chloride salt in Example 7 can also improve the polishing effect. This is because adding organic solvents can reduce viscosity and accelerate ion exchange.

[0122] 5. It can be seen from the experimental results of Example 12 that the polishing brightness can be further improved by adding a brightener. On the basis of Example 7, by adding a brightener such as sugar, the surface roughness of the polished titanium alloy part can be further reduced from 0.79 μm to 0.41 μm.

[0123] 6. From the experimental results of Comparative Examples 1-3, it can be seen that when using organic solvents such as ethanol and DMF, the current is too low and the polishing effect is poor, which is not as good as the polishing effect of the embodiment using ionic liquids.

[0124] Brass metal solid electrolytic polishing experiment

[0125] The brass solid electrolytic polishing application experiment was carried out using the metal solid electrolytic polishing medium Example 7 prepared above. The surface roughness of the brass before polishing was 1.86 μm.

[0126] The method of solid electrolytic polishing of brass parts is as follows:

[0127] The brass piece was connected to the positive electrode of the power supply of the electrochemical polishing device, and the metal solid electrolytic polishing medium Example 7 was placed in a metal net bag and connected to the negative electrode of the power supply of the electrochemical polishing device. The electrochemical polishing device was powered on for electrolytic polishing, and the brass piece to be polished and the metal electrolytic polishing medium underwent relative frictional motion during electrolytic polishing. The applied voltage was 60V, the relative motion rate was 90r / min, and the polishing time was 60min.

[0128] The results of the brass metal solid electrolytic polishing experiment show that after the brass is polished using the metal solid electrolytic polishing medium of Example 7, its surface roughness is reduced from 1.86 μm before polishing to 0.19 μm after polishing.

[0129] Stainless steel metal solid electrolytic polishing experiment

[0130] The solid electrolytic polishing application experiment of stainless steel 316 was carried out using the metal solid electrolytic polishing medium Example 7 prepared above. The surface roughness of the stainless steel 316 before polishing was 2.97 μm.

[0131] The method of solid electrolytic polishing of stainless steel parts is as follows:

[0132] The stainless steel part 316 is connected to the positive electrode of the power supply of the electrochemical polishing device, and the metal solid electrolytic polishing medium Example 7 is placed in a metal net bag and connected to the negative electrode of the power supply of the electrochemical polishing device. The electrochemical polishing device is powered on for electrolytic polishing, and the stainless steel part to be polished and the metal electrolytic polishing medium undergo relative frictional motion during electrolytic polishing. The applied voltage is 60V, the relative motion rate is 90r / min, and the polishing time is 60min.

[0133] The results of the metal solid electrolytic polishing experiment on stainless steel 316 show that after the stainless steel is polished using the metal solid electrolytic polishing medium of Example 7, its surface roughness is reduced from 2.97 μm before polishing to 0.37 μm after polishing.

[0134] Aluminum alloy metal solid electrolytic polishing experiment

[0135] The solid electrolytic polishing application experiment of aluminum alloy was carried out using the metal solid electrolytic polishing medium Example 7 prepared above. The surface roughness of the aluminum alloy before polishing was 1.58 μm.

[0136] The method of solid electrolytic polishing of aluminum alloy parts is as follows:

[0137] The aluminum alloy piece was connected to the positive electrode of the power supply of the electrochemical polishing device, and the metal solid electrolytic polishing medium Example 7 was placed in a metal net bag and connected to the negative electrode of the power supply of the electrochemical polishing device. The electrochemical polishing device was powered on for electrolytic polishing, and the aluminum alloy piece to be polished and the metal electrolytic polishing medium underwent relative frictional motion during electrolytic polishing. The applied voltage was 60V, the relative motion rate was 90r / min, and the polishing time was 60min.

[0138] The experimental results of the solid electrolytic polishing of aluminum alloy show that after the aluminum alloy is polished with the solid electrolytic polishing medium of Example 7, its surface roughness is reduced from 1.58 μm before polishing to 0.24 μm after polishing.

[0139] It can be seen from the above experimental results that the present invention applies ionic liquids to solid electrolytic polishing of high-strength and corrosion-resistant metals such as titanium alloys, nickel alloys, tungsten alloys, copper alloys, aluminum alloys, magnesium alloys or steel, which can achieve fast and good polishing effects, has the characteristics of low carbon, environmental protection and high efficiency, and has broad application prospects.

[0140] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A polishing medium for metal solid electrolytic polishing, characterized in that: A solid particulate matter comprising an ionic liquid; The ionic liquid is used as electrolyte and solvent in electrolytic polishing of metal solids; The solid particles have a porous structure and groups capable of adsorbing and complexing metal ions; The group that adsorbs and complexes metal ions includes at least one of a carboxyl group, an amine group, and a hydroxyl group; The solid particles include one or more of ion exchange resin, silica gel, and molecular sieve.

2. The polishing medium according to claim 1, characterized in that The resistivity of the ionic liquid is ≤5×10 5 Ω / cm.

3. The polishing medium according to claim 1 or 2, characterized in that The ionic liquid is a halogenated ionic liquid.

4. The polishing medium according to claim 1, characterized in that The metal includes at least one of titanium alloy, nickel alloy, tungsten alloy, copper alloy, aluminum alloy, magnesium alloy and steel.

5. The polishing medium according to claim 1, characterized in that The mass ratio of the solid particles to the ionic liquid is 100:(0.1~100).

6. The polishing medium according to claim 1, 2, 4 or 5, characterized in that The polishing medium further contains at least one of salt, brightener and solvent.

7. The polishing medium according to claim 6, characterized in that The salt includes at least one of sulfate, chloride, zinc, sodium, potassium and ammonium salts.

8. The polishing medium according to claim 6, characterized in that The brightener includes at least one of glucose, saccharin, starch, sucrose and benzotriazole.

9. The polishing medium according to claim 6, characterized in that The solvent includes at least one of water, small molecule alcohol, small molecule ketone, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran and dioxane.

10. The polishing medium according to claim 6, characterized in that The mass ratio of the solid particles to the salt is 100:(0.1~30); And / or, the mass ratio of the solid particles to the brightener is 100:(0.01-20); And / or, the mass ratio of the solid particles to the solvent is 100:(0.001~100).

11. A method for electrolytic polishing of metal solids, characterized in that: The polishing medium according to any one of claims 1 to 10 is used to perform solid electrolytic polishing on metal.

Images