Manufacturing method of ultrahigh-precision screw extrusion equipment die head

Abstract

The invention provides a manufacturing method of an ultrahigh-precision screw extrusion equipment die head, and belongs to the technical field of die head preparation, and the manufacturing method comprises the following steps: processing a titanium alloy material to obtain a primary gap height which is greater than a required gap height to obtain an initial die head, immersing the initial die head into an organic solvent and an alkaline solution in sequence, and cleaning; a gap of the cleaned initial die head is fully coated with a lubricant, a steel sheet is inserted into the gap of the initial die head, and the thickness of the steel sheet is the same as the height of the gap needed by the final die head of the screw extruder; pressure is applied to the initial die head, so that a gap in the initial die head is tightly attached to the steel sheet, aqua regia is put into the initial die head to wait for partial corrosion of the steel sheet, and the remaining steel sheet is taken out; and cleaning and drying the initial die head from which the steel sheet is taken out, smearing a chemical polishing solution, and detecting the height of a gap to obtain a final die head of the screw extruder. The extrusion die head produced at low cost meets the gap height of 2-10 microns, and the process is simple and suitable for batch production.

Description

Technical Field

[0001] The invention relates to the technical field of die head preparation, and in particular to a method for manufacturing a die head of ultra-high precision screw extrusion equipment. Background Art

[0002] With the development of new energy materials and precision electronic components, thin film materials are widely used in cutting-edge scientific and technological fields such as flexible thin film batteries, conductive films, transparent electrodes, and functional coatings. These applications have extremely high requirements on the quality, thickness uniformity, and surface flatness of thin film materials, and extrusion die technology has an important impact on these properties. However, at present, traditional extrusion dies are difficult to meet the high-precision gap requirements of 5 microns and below. Ultra-precision machining or laser micromachining can be used in the existing technology to improve the accuracy of the gap, but the above-mentioned technical means have problems such as high cost, long cycle, high difficulty, and mass production bottlenecks. Therefore, it is necessary to provide an economical, controllable, and industrially friendly high-precision extrusion equipment die production process. Summary of the invention

[0003] In view of this, the present invention provides a method for manufacturing an ultra-high precision screw extrusion equipment die head, which can produce an extrusion die head at low cost and meet the gap height of 2 to 10 microns. The process is simple and suitable for mass production.

[0004] To achieve the above object, the present invention provides a method for manufacturing a die head of an ultra-high precision screw extruder, comprising the following steps: S1, selecting titanium alloy as the main material of the die, processing the titanium alloy material to obtain an initial gap height to obtain an initial die, wherein the initial gap height is greater than the required gap height, and immersing the initial die in an organic solvent and an alkaline solution in turn to clean it; S2, coating the cleaned initial die with lubricant, inserting a steel sheet into the gap of the initial die, wherein the thickness of the steel sheet is the same as the gap height required for the final die of the screw extruder; S3, applying pressure to the initial die head to make the gap in the initial die head fit closely with the steel sheet, putting in aqua regia to wait for the steel sheet to be partially corroded, and taking out the remaining steel sheet; S4, cleaning and drying the initial die head after taking out the steel sheet, applying chemical polishing liquid, detecting the gap height, and obtaining the final die head of the screw extruder.

[0005] Optionally, the organic solvent is acetone; and the alkaline solution is sodium bicarbonate solution.

[0006] The acetone and sodium bicarbonate used in the present invention can remove impurities and acidic substances on the surface of the initial die head.

[0007] Optionally, the lubricant is fluorine-containing oil.

[0008] Optionally, the model of the fluorine-containing oil is Superlube fluorine-containing oil.

[0009] The fluorine-containing oil used in the present invention does not react with highly corrosive chemical media such as aqua regia below 100° C., contains polytetrafluoroethylene particles, can form a smooth solid lubricating film, reduces the friction coefficient, and has anti-wear, anti-rust and anti-corrosion properties. It is non-toxic and odorless, has a wide operating temperature range and is environmentally friendly, which is conducive to the subsequent removal of the steel sheet.

[0010] Optionally, the aqua regia is a mixture of nitric acid and hydrochloric acid, and the volume ratio of the nitric acid to the hydrochloric acid is 1:3.

[0011] The present invention uses aqua regia to corrode the steel sheet, but aqua regia cannot corrode titanium alloy. Therefore, after corroding part of the steel sheet, the steel sheet can be easily taken out. After the steel sheet is taken out, its thickness is the gap height, and a simple process can be used to prepare a high-precision gap.

[0012] Optionally, the time for waiting for the steel sheet to be partially corroded by placing it in aqua regia is 10 to 30 minutes.

[0013] Optionally, the initial gap height is 0.2-0.5 mm, and the thickness of the steel sheet is 2-10 μm.

[0014] Optionally, the chemical polishing liquid is a phosphoric acid-sulfuric acid polishing liquid.

[0015] Optionally, the phosphoric acid-sulfuric acid polishing liquid includes chromic anhydride and glycerol.

[0016] The mixed acid of phosphoric acid and sulfuric acid used in the present invention can corrode the oxide film and metal titanium on the titanium surface, chromic anhydride can play a passivation role to prevent excessive corrosion, and glycerol can increase the viscosity of the polishing liquid, making the polishing process more stable and helping to improve the surface quality.

[0017] Optionally, the cleaning is to rinse the initial die head with clean water and then perform ultrasonic cleaning.

[0018] The above technical solution of the present invention includes at least the following beneficial effects: The preparation method provided by the present invention realizes the ultra-high precision of 2 to 10 microns of the extrusion die at low cost, is suitable for the preparation of the extrusion die of thin-film battery materials, reduces the complexity and cost of high-precision processing of traditional extrusion dies, and is simple in process and convenient for mass production. The use of cleaning and lubricant application procedures improves the quality and performance of the extrusion die, facilitates the removal of steel sheets, prolongs the service life of the die, and makes the use of the extrusion die more stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure is a process flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0021] Example 1 High-precision extrusion equipment die head for preparing 5 micron gap Initial die processing and cleaning: Choose titanium alloy as the main material of the die, process the titanium alloy into an initial die with a gap of 0.5 mm, soak the initial die with acetone, then wipe it lightly with a clean cloth or brush and rinse with water; then wipe it with an alcohol cotton ball; then soak it with sodium bicarbonate solution to remove acidic substances, and then rinse with water.

[0022] Apply lubricant and insert steel sheet: Apply Superlube fluorinated oil lubricant to the cleaned die gap and insert a 5-micron thick steel sheet into the die gap.

[0023] Compacting treatment and steel sheet corrosion: vertical pressure is applied by a hydraulic press to make the die head gap fit tightly with the steel sheet, and the die head is immersed in aqua regia to wait for the steel sheet to corrode. Aqua regia is a mixture of nitric acid and hydrochloric acid, and the volume ratio of the nitric acid to the hydrochloric acid is 1:3; after waiting for 10 minutes, the steel sheet is partially corroded and easy to take out. After the steel sheet is taken out, the thickness of the steel sheet is the gap height of the die head.

[0024] Cleaning and testing: First rinse the die head with plenty of clean water to remove residual aqua regia and impurities; then perform ultrasonic cleaning; polish with a phosphoric acid-sulfuric acid polishing solution containing a small amount of chromic anhydride and glycerol, and then use a microscope to detect that the gap height is 5 microns.

[0025] Example 2 High-precision extrusion equipment die head for preparing 2 micron gap Initial die processing and cleaning: Choose titanium alloy as the main material of the die, process the titanium alloy into an initial die with a gap of 0.2 mm, soak the initial die with acetone, then wipe it lightly with a clean cloth or brush and rinse with water; then wipe it with an alcohol cotton ball; then soak it with sodium bicarbonate solution to remove acidic substances, and then rinse with water.

[0026] Apply lubricant and embed steel sheet: Apply fluorine-containing oil lubricant to the cleaned die gap and insert a 2-micron thick steel sheet into the die gap.

[0027] Compacting treatment and steel sheet corrosion: vertical pressure is applied by a hydraulic press to make the die head gap fit tightly with the steel sheet, and the die head is immersed in aqua regia to wait for the steel sheet to corrode. Aqua regia is a mixture of nitric acid and hydrochloric acid, and the volume ratio of the nitric acid to the hydrochloric acid is 1:3; after waiting for 30 minutes, the steel sheet is partially corroded and easy to take out. After the steel sheet is taken out, the thickness of the steel sheet is the gap height of the die head.

[0028] Cleaning and testing: First rinse the die head with plenty of clean water to remove residual aqua regia and impurities; then perform ultrasonic cleaning; polish with phosphoric acid-sulfuric acid polishing liquid, and then use a microscope to detect the gap height of 2 microns.

[0029] Example 3 High-precision extrusion equipment die head for preparing 10 micron gap Initial die processing and cleaning: Choose titanium alloy as the main material of the die, process the titanium alloy into an initial die with a gap of 0.4 mm, soak the initial die with acetone, then wipe it lightly with a clean cloth or brush and rinse with water; then wipe it with an alcohol cotton ball; then soak it with sodium bicarbonate solution to remove acidic substances, and then rinse with water.

[0030] Apply lubricant and embed steel sheet: Apply fluorine-containing oil lubricant to the cleaned die gap and insert a 10-micron thick steel sheet into the die gap.

[0031] Compacting treatment and steel sheet corrosion: vertical pressure is applied by a hydraulic press to make the die head gap fit tightly with the steel sheet, and the die head is immersed in aqua regia to wait for the steel sheet to corrode. Aqua regia is a mixture of nitric acid and hydrochloric acid, and the volume ratio of the nitric acid to the hydrochloric acid is 1:3; after waiting for 20 minutes, the steel sheet is partially corroded and easy to take out. After the steel sheet is taken out, the thickness of the steel sheet is the gap height of the die head.

[0032] Cleaning and testing: First rinse the die head with plenty of clean water to remove residual aqua regia and impurities; then perform ultrasonic cleaning; polish with phosphoric acid-sulfuric acid polishing liquid, and then use a microscope to detect the gap height of 10 microns.

[0033] Example 4 Extrusion test using a high-precision die with a 10-micron gap height The die head with a gap of 10 microns prepared in Example 3 was installed on a screw extruder (conventional screw extrusion equipment on the market). According to the operating process of the screw extruder, polyethylene powder (30 mesh) was added, the front-stage heating temperature was set to 180°C, the rear-end heating temperature was set to 200°C, the screw rotation speed was 20 rpm, a screw extrusion test was carried out, and a polyethylene film was obtained at the die head outlet. The thickness of the polyethylene film was detected by microscope and was 10 microns.

[0034] In the present invention, unless otherwise clearly stipulated and limited, for example, it can be a fixed connection, a detachable connection, or an integrated one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0035] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for manufacturing a die head of an ultra-high precision screw extruder, characterized in that: The following steps are involved: S1, selecting titanium alloy as the main material of the die, processing the titanium alloy material to obtain an initial gap height to obtain an initial die, wherein the initial gap height is greater than the required gap height, and immersing the initial die in an organic solvent and an alkaline solution in turn to clean it; S2, coating the cleaned initial die with lubricant, inserting a steel sheet into the gap of the initial die, wherein the thickness of the steel sheet is the same as the gap height required for the final die of the screw extruder; S3, applying pressure to the initial die head to make the gap in the initial die head fit closely with the steel sheet, putting in aqua regia to wait for the steel sheet to be partially corroded, and taking out the remaining steel sheet; S4, cleaning and drying the initial die head after taking out the steel sheet, applying chemical polishing liquid, detecting the gap height, and obtaining the final die head product of the screw extruder.

2. The method for making a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The organic solvent is acetone; and the alkaline solution is a sodium bicarbonate solution.

3. The method for making a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The lubricant is fluorine-containing oil.

4. The method for manufacturing the die head of the ultra-high precision screw extruder according to claim 1, characterized in that: The model of the fluorinated oil is Superlube fluorinated oil.

5. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The aqua regia is a mixture of nitric acid and hydrochloric acid, and the volume ratio of the nitric acid to the hydrochloric acid is 1:

3.

6. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The time for waiting for the steel sheet to be partially corroded after putting it in aqua regia is 10 to 30 minutes.

7. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The initial gap height is 0.2-0.5 mm, and the thickness of the steel sheet is 2-10 μm.

8. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The chemical polishing liquid is a phosphoric acid-sulfuric acid polishing liquid.

9. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 8, characterized in that: The phosphoric acid-sulfuric acid polishing liquid includes chromic anhydride and glycerol.

10. The method for manufacturing a die head of an ultra-high precision screw extruder according to claim 1, characterized in that: The cleaning is to rinse the initial die head with clean water and then perform ultrasonic cleaning.

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