CN111250806A - A kind of electrolyte and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of electrochemistry and discloses an electrolytic solution comprising sodium chloride, ethanol and ethylene glycol. In the present invention, ethanol and ethylene glycol are used as solvents to dissolve sodium chloride to obtain a non-aqueous electrolyte solution, wherein ethanol and ethylene glycol can completely dissolve sodium chloride and have higher electrical conductivity. The prepared electrolyte has lower viscosity and can obtain higher flow rate in jet electrolysis; meanwhile, the electrolyte has higher boiling point and good stability. The electrolyte can effectively avoid the corrosion of the titanium alloy surface and the surface roughness caused during the processing, and the surface roughness Ra of the prepared titanium alloy material can be as low as 0.082um. The electrolyte of the invention has the advantages of simple preparation process, low cost of raw materials and environmental protection.

Description

A kind of electrolyte and preparation method thereof

technical field

The invention belongs to the field of electrochemistry, and particularly relates to an electrolyte and a preparation method thereof.

Background technique

Electrochemical machining, also known as electrochemical machining, is a process method based on the principle of anodic dissolution in the electrolytic process, and the workpiece is processed into a certain shape and size with the help of a pre-shaped cathode. In the process of processing, a low-voltage, high-current density direct current or pulse current is passed between the electrodes, and a high-speed flowing electrolyte is passed at the same time. The cathode workpiece is advanced at a certain speed to maintain a constant small gap between the electrodes. The anode workpiece follows Faraday's law and dissolves continuously according to the shape of the cathode workpiece until its shape and size meet the requirements.

This technology was mainly used in the processing of aviation turbine blades and barrel rifling in the early days, and then gradually expanded to the fields of forging cavity, deep hole, small hole, section blade, integral impeller and deburring processing. With the increasing demand for rapid manufacturing and process flexibility of electrolytic machining technology, based on the electrolytic machining mechanism, combined with numerical control technology, electrolytic jet machining technology has been gradually developed. It not only inherits many advantages of electrolytic machining, but also has high process flexibility and machining accuracy.

Titanium alloys are widely used in the manufacture of key components in the industrial field due to their excellent properties. However, as a typical difficult-to-machine material, titanium alloys face many difficulties in traditional processing techniques. Electrolytic jet machining, as a non-contact flexible machining, has no thermal influence during the machining process and is not affected by the hardness of the workpiece. It has become a potential technology for precision machining of titanium alloys. However, electrolytic jet processing uses a water-based electrolyte, using water as a solvent, and water has a certain oxidizing property, and a side reaction of water electrolysis will occur to form oxygen. For conventional target materials, this side reaction does not cause a degraded anode interface. However, for titanium alloys, because the titanium element is extremely active, the surface of titanium and titanium alloys is easy to react with oxidizing media, and the anode generates an extremely dense oxide layer, resulting in uneven corrosion, resulting in rough surface quality and degraded shape accuracy.

Therefore, it is desirable to provide an electrolyte that can effectively avoid surface roughness caused by corrosion of the titanium alloy surface during processing.

SUMMARY OF THE INVENTION

The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. Therefore, the present invention proposes an electrolyte, which can effectively avoid surface roughness caused by surface corrosion of titanium alloy and improve the surface precision of titanium alloy.

An electrolyte that includes sodium chloride, ethanol, and ethylene glycol.

Preferably, an electrolyte solution, in parts by weight, includes the following components: 1-8 parts of sodium chloride, 3-15 parts of ethanol, and 80-95 parts of ethylene glycol.

Further preferably, an electrolyte, in parts by weight, includes the following components: 3-5 parts of sodium chloride, 5-10 parts of ethanol, and 85-92 parts of ethylene glycol.

Most preferably, an electrolyte, in parts by weight, includes the following components: 5 parts of sodium chloride, 10 parts of ethanol, and 85 parts of ethylene glycol.

A preparation method of electrolyte, comprising the following steps:

Sodium chloride, ethylene glycol and ethanol are weighed, mixed and dissolved to prepare the electrolyte.

Concrete, a kind of preparation method of electrolyte, comprises the following steps:

Weigh ethylene glycol and ethanol according to the mass ratio, mix them evenly, then weigh sodium chloride and add it, and stir to dissolve the powder completely, that is, the electrolyte solution is prepared.

An electrolytic jet machining process of titanium alloy, comprising the following steps:

(1) install the titanium alloy workpiece in the electrolysis device;

(2) inject described electrolyte in electrolyzer, pressurize, make described electrolyte form high-speed flowing electrolyte, namely electrolyte jet;

(3) Turn on the power supply and the displacement device, and use the electrolyte jet described in step (2) to process the titanium alloy.

The pressure of the pressurization process in step (2) is 0.1-0.5Mpa; preferably, the pressure of the pressurization process in step (2) is 0.2-0.3Mpa.

During the processing of step (3), the moving speed of the nozzle is 3-15mm/s, the processing current is 0.1-0.3A, and the processing gap is 0.3-1mm.

A titanium alloy material is prepared by electrolysis of the electrolyte.

In the process of jet electrolytic machining of titanium alloys, on the one hand, titanium alloys are very easy to form oxide layers, and the formed oxide layers are extremely stable; on the other hand, there is a small current density distributed at the edge of the electrolyte jet. The surface of the alloy will undergo oxidation reaction with water molecules to form a stable oxide layer. It is difficult to completely remove the oxide layer. After the oxide layer is partially damaged, the corrosion rate is faster, and the accuracy is deteriorated after corrosion.

Therefore, in principle, it is very important to eliminate water molecules to avoid the formation of oxide layers. However, the electrolyte of traditional electrolysis uses water as the solvent, and there must be a large number of water molecules. The inventors found that ethanol and ethylene glycol are used as solvents to dissolve sodium chloride to prepare a non-aqueous electrolyte solution, wherein ethanol and ethylene glycol can completely dissolve sodium chloride and have higher conductivity. The prepared electrolyte has lower viscosity and can obtain higher flow rate in jet electrolysis; meanwhile, the electrolyte has higher boiling point and good stability.

Adding ethanol in the preparation of the electrolyte can stabilize the ethylene glycol solvent, because ethylene glycol has a certain hygroscopicity. After being exposed to the air, it will absorb the water vapor in the air and bring it into the electrolyte. Causes oxidation of titanium alloys, resulting in poor accuracy, while adding ethanol can reduce the hygroscopicity of ethylene glycol. On the other hand, adding ethanol can reduce the viscosity of the electrolyte, and can form a high-speed flow field in the electrolytic machining gap to ensure the machining accuracy.

With respect to the prior art, the beneficial effects of the present invention are as follows:

(1) the present invention adopts ethanol and ethylene glycol as solvent, dissolves sodium chloride, makes non-aqueous-based electrolyte, wherein ethanol and ethylene glycol can both completely dissolve sodium chloride, also have higher conductivity. The prepared electrolyte has lower viscosity and can obtain higher flow rate in jet electrolysis; meanwhile, the electrolyte has higher boiling point and good stability. The electrolyte can effectively avoid the corrosion of the titanium alloy surface and the surface roughness caused during the processing, and the surface roughness Ra of the prepared titanium alloy material can be as low as 0.082um.

(2) The electrolyte of the present invention has the advantages of simple preparation process, low cost of raw materials and environmental protection.

Detailed ways

In order to make those skilled in the art understand the technical solutions of the present invention more clearly, the following examples are now given for illustration. It should be noted that the following examples do not limit the protection scope of the present invention.

Example 1

Weigh 9200 g of ethylene glycol and 500 g of ethanol solvent, mix well, weigh 300 g of sodium chloride, add it to the electrolyte tank containing the mixed solvent, and stir until the powder is completely dissolved to obtain an electrolyte. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. During the processing, firstly install the stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the anode and cathode as tools and workpieces, inject the electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor 0.5Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 10mm/s, processing current 0.15A, processing gap 0.5mm, nozzle movement trajectory superimposed 200 times, in 200s processing time, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. The titanium alloy surface structure with mirror surface is 0.06mm, the machined surface is extremely smooth, and the average roughness reaches Ra=0.084um.

Example 2

Weigh 8500 g of ethylene glycol and 1000 g of ethanol solvent, mix well, weigh 500 g of sodium chloride, add it to the electrolyte tank containing the mixed solvent, and stir until the powder is completely dissolved to prepare an electrolyte. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. In the process of processing, firstly install a stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the cathode and anode as tools and workpieces, inject electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor. 0.3Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 10mm/s, processing current 0.15A, processing gap 0.5mm, nozzle movement trajectory superimposed 200 times, in 200s processing time, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. The titanium alloy surface structure with mirror surface is 0.06mm, the machined surface is extremely smooth, and the average roughness reaches Ra=0.082um.

Example 3

Weigh 9500 g of ethylene glycol and 1500 g of ethanol solvent, mix well, weigh 800 g of sodium chloride, add it to the electrolyte tank containing the mixed solvent, and stir until the powder is completely dissolved to prepare an electrolyte. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. During the processing, firstly install the stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the anode and cathode as tools and workpieces, inject the electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor 0.2Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 10mm/s, processing current 0.15A, processing gap 0.5mm, nozzle movement trajectory superimposed 200 times, in 200s processing time, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. The titanium alloy surface structure with mirror surface is 0.06mm, the machined surface is extremely smooth, and the average roughness reaches Ra=0.086um.

Example 4

Weigh 8000 g of ethylene glycol and 300 g of ethanol solvent, mix well, weigh 100 g of sodium chloride, add it to the electrolyte tank containing the mixed solvent, and stir until the powder is completely dissolved to obtain an electrolyte solution. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. During the processing, firstly install the stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the anode and cathode as tools and workpieces, inject the electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor 0.3Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 10mm/s, processing current 0.15A, processing gap 0.5mm, nozzle movement trajectory superimposed 200 times, in 200s processing time, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. The titanium alloy surface structure with mirror surface is 0.06mm, the machined surface is extremely smooth, and the average roughness reaches Ra=0.087um.

Example 5

Weigh 8500 g of ethylene glycol and 1000 g of ethanol solvent, mix well, weigh 500 g of sodium chloride, add it to the electrolyte tank containing the mixed solvent, and stir until the powder is completely dissolved to prepare an electrolyte. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. During the processing, firstly install the stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the anode and cathode as tools and workpieces, inject the electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor 0.3Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 15mm/s, processing current 0.2A, processing gap 0.8mm, nozzle movement trajectory superimposed 200 times, in the processing time of 200s, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. The titanium alloy surface structure with mirror surface is 0.06mm, the machined surface is extremely smooth, and the average roughness reaches Ra=0.083um.

Comparative Example 1

Weigh 200g of sodium chloride and 800g of water, mix and dissolve completely to prepare an electrolyte. The precision jet electrolytic machining test of titanium alloy is carried out through the electrolyte. The test device includes an XYZ axis displacement platform, an electrolytic machining power source, a machining tank and a current acquisition system. During the processing, firstly install the stainless steel nozzle with an inner diameter of 1.11mm and a titanium alloy sheet with a thickness of 1.5mm on the anode and cathode as tools and workpieces, inject the electrolyte into the electrolytic cell, and apply pressure to the electrolytic cell through the air compressor 0.3Mpa, so that the electrolyte is shot to the workpiece through the nozzle to form an electrolyte jet. After the formation of the electrolyte jet is stable, the processing power supply and the displacement device are turned on, and the precision processing of the titanium alloy surface structure is carried out. The parameters used for processing are: nozzle moving speed 10mm/s, processing current 0.15A, processing gap 0.5mm, nozzle movement trajectory superimposed 200 times, in 200s processing time, the length of 10mm, the width of 1.8mm and the depth of 1.8mm can be processed. It is a titanium alloy material of 0.06mm, and the average surface roughness Ra=12.4um.

Comparative Example 2

The difference between Comparative Example 2 and Example 2 is that 8,500 g of ethylene glycol and 1,000 g of ethanol solvent in Example 2 were replaced with 9,500 g of water, and the rest of the formula and processing were the same as those of Example 2. The average surface roughness of the prepared titanium alloy material is Ra=2.4um.

Comparative Example 3

The difference between Comparative Example 3 and Example 2 is that 1000 g of ethanol in Example 2 was replaced with ethylene glycol, and the rest of the formula and processing were the same as those of Example 2. The average surface roughness Ra=0.1um of the prepared titanium alloy material.

Claims (8)

1. An electrolyte, comprising sodium chloride, ethanol, and ethylene glycol.

2. The electrolyte according to claim 1, comprising the following components in parts by weight: 1-8 parts of sodium chloride, 3-15 parts of ethanol and 80-95 parts of ethylene glycol.

3. The electrolyte according to claim 2, comprising the following components in parts by weight: 3-5 parts of sodium chloride, 5-10 parts of ethanol and 85-92 parts of ethylene glycol.

4. The electrolyte according to claim 3, comprising the following components in parts by weight: 5 parts of sodium chloride, 10 parts of ethanol and 85 parts of ethylene glycol.

5. The preparation method of the electrolyte is characterized by comprising the following steps:

and weighing sodium chloride, ethylene glycol and ethanol, mixing and dissolving to obtain the electrolyte.

6. The electrolytic jet machining process of the titanium alloy is characterized by comprising the following steps of:

(1) mounting a titanium alloy workpiece in an electrolysis device;

(2) injecting the electrolyte solution of any one of claims 1 to 4 into an electrolytic cell, and pressurizing to form the electrolyte solution into an electrolyte solution jet;

(3) and (3) starting a power supply and a displacement device, and processing the titanium alloy by adopting the electrolyte jet flow in the step (2).

7. The electrolytic jet machining process according to claim 6, wherein the moving speed of the nozzle during the machining in the step (3) is 3 to 15mm/s, the machining current is 0.1 to 0.3A, and the machining gap is 0.3 to 1 mm.

8. The use of the electrolyte according to any one of claims 1 to 4 in the preparation of a titanium alloy material.