CN114558992B - Method for manufacturing micro-perforated metal plate - Google Patents

Abstract

The invention discloses a method for manufacturing a micro-perforated metal plate. Specifically, liquid metal is injected into a mold assembled from two independent parts of a concave template and filling particles, and solidified, cooled, and demolded to obtain perforations with variable cross-sections. The micro-perforated metal plate; the hole diameter is controlled by adjusting the injection amount of the liquid metal or the size of the filling particles. The invention can meet the perforation aperture requirements of any micro-perforated plate, is suitable for the production of various metal plates, and has the characteristics that the thicker the plate is, the smaller the perforation aperture is; the mold can be used repeatedly, and it is easy to adjust the size or replace the damage ,saving cost.

Description

A method of manufacturing a micro-perforated metal plate

technical field

The invention relates to the technical field of noise control, in particular to a method for manufacturing a micro-perforated metal plate.

Background technique

声抗

其中t为板厚，d为孔径，σ为穿孔率。由此可知，适当增加板厚，减小穿孔孔径，有利于提高微穿孔板的吸声性能。此外，采用变截面穿孔可进一步提升微穿孔板的吸声性能。The resonant sound-absorbing structure of the micro-perforated plate is widely used in the field of noise control. The perforated hole diameter is less than 1mm, and the perforation rate is not more than 5%. The sound absorption performance is better than that of the ordinary perforated plate resonant sound-absorbing structure. According to the sound absorption theory of micro-perforated plates, the sound absorption coefficient and frequency bandwidth that characterize the sound absorption characteristics of micro-perforated plates are mainly determined by the acoustic resistance r and acoustic reactance wm of the structure. Acoustic resistance

Acoustic reactance

Where t is the plate thickness, d is the hole diameter, and σ is the perforation rate. It can be seen that appropriately increasing the thickness of the plate and reducing the diameter of the perforated hole is conducive to improving the sound absorption performance of the micro-perforated plate. In addition, the use of variable cross-section perforations can further improve the sound absorption performance of the micro-perforated panels.

Metal sheets have attracted much attention due to their high mechanical strength, high temperature resistance, and corrosion resistance. Realizing the perforation of less than 1mm on a metal plate with a certain thickness and hardness is a technical difficulty in the production of micro-perforated metal plates. The traditional production of micro-perforated metal plates mainly adopts the method of mechanically punching, drilling, pressing, and piercing the metal plate. This method can generally process holes with a diameter of more than 0.5mm. It is often used to process plates with low hardness such as aluminum plates. It is particularly difficult to perforate a metal plate with high hardness, and the perforation aperture generally does not exceed the thickness of the steel plate. The use of laser perforation technology can meet the requirements of different perforation apertures, and is suitable for the processing of various plates, but the processing cost is high and the time is long.

The patent specification whose notification number is CN1136082C discloses a method for processing microporous metal plates by chemical corrosion, which is carried out in several steps in the following order:

First, according to the requirements of sound absorption, design the parameters of the microporous plate, including micropore diameter, perforation rate, hole spacing and hole shape, draw the layout of the microholes, and make a transparent film;

Second, clean the metal plate to be processed, and then stick the resist photosensitive film or apply the resist photosensitive adhesive on the front and back of the metal plate;

Third, place two transparent films printed with the layout of the micropores on the front and back sides of the metal plate with a resist photosensitive coating, and expose them together;

Fourth, put the exposed metal plate into the developing solution for developing treatment. After developing, the resist film at the position of the microhole disappears, exposing the metal surface;

Fifth, in the corrosion tank, spray the developed metal plate with a solution made of ferric chloride and acidic substances. After spraying, the metal exposed on the metal surface will be corroded, and the metal plate with the anti-corrosion film will be corroded. metal is preserved;

Sixth, wash the metal plate with clean water, and then soak the metal plate with alkaline solution to remove the anti-corrosion layer.

The above-mentioned method can produce metal plates with a hole diameter of 0.1-0.4 mm in large quantities, but it is mainly suitable for the processing of thin metal plates, and the chemical etchant is not friendly to the environment.

Contents of the invention

The purpose of the present invention is to provide a method for manufacturing a micro-perforated metal plate, which can meet the requirements of any micro-perforated aperture and is suitable for making micro-perforated plates of various metal materials.

A method for manufacturing a micro-perforated metal plate. Liquid metal is injected into a mold assembled from two independent parts of a concave template and filling particles, and solidified, cooled, and demolded to obtain a micro-perforated metal plate with variable cross-section perforations; The pore diameter is controlled by adjusting the injection amount of the liquid metal or the size of the filling particles.

Preferably, the concave formwork includes a base plate and side walls embedded in the base plate and located around it, and the base plate is provided with several platform-shaped (including circular truncated or edge-shaped) perforations, and the filling particles are used to embed the perforated holes. Inside, and the filled particles are in the shape of cones or terraces. Wherein, the top horizontal section size of the filling particles is smaller than the perforation hole diameter of the target micro-perforated metal plate.

Preferably, the filling particles are inserted into the perforations from below the bottom plate, the top of the filling particles passes through the upper surface of the bottom plate, the bottom of the filling particles exceeds the bottom of the bottom plate, and the upper opening of the perforation closely fits the filling particles.

Specifically, the concave formwork is inverted so that the filling particles are inserted into the platform-shaped perforations from the bottom of the bottom plate, the top of the filling particles passes through the upper surface of the bottom plate, the bottom of the particles exceeds the bottom of the bottom plate, and the upper opening of the platform-shaped perforation of the bottom plate is closely attached to the filling particles. combine. After the assembly is complete, place the mold upright.

Preferably, the bottom of the filling particles is provided with a handle for easy grasping by the manipulator, which facilitates the placement of the filling particles into the perforation of the concave formwork platform and facilitates the replacement of damaged filling particles during the production process.

The thickness of the liquid metal injection is smaller than the height of the filling particles protruding from the upper surface of the bottom plate.

Preferably, when the size of the mold is constant, the injection amount of the liquid metal is increased to increase the thickness of the liquid metal layer and reduce the hole diameter; when the thickness of the target micro-perforated metal plate is constant, the concave template remains unchanged and decreases The cone angle or the included angle between the side edges of the filled particles reduces the pore diameter.

Preferably, the filling particles and the concave template are made of high temperature resistant materials.

Preferably, the bottom plate and the side wall are integrally formed.

Beneficial effects of the present invention:

(1) The present invention is suitable for making all kinds of micro-perforated metal plates, which can meet the requirements of any micro-perforated aperture, and the plate has the characteristics that the larger the thickness, the smaller the perforated aperture, which is beneficial to improve the sound absorption performance and Mechanical strength.

(2) The mold in the present invention can be used repeatedly. Compared with the one-piece mold, the concave formwork and the filling particles are independent of each other, so it is easy to adjust the size or damage and replace, saving cost.

Description of drawings

Fig. 1 is the schematic diagram of filling particle and concave formwork of the present invention;

Fig. 2 is a schematic diagram of making the microporous metal plate of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example

A micro-perforated steel plate with a plate thickness of 0.6 mm and a square of 100 mm×100 mm was produced, with a perforation diameter of 0.4 mm, a hole spacing of 3 mm, and a perforation rate of 1.1%.

The specific implementation steps are as follows:

Ceramics are used as materials to make the filling particles 1 and the concave template. As shown in Figure 1, the filling particle 1 is conical, with a height H of 3.2mm and a bottom diameter D of 3.2mm; the bottom of the filling particle 1 has a hexagonal nut, the size M of the hexagonal nut is 3.5mm, and the thickness K is 3mm. Concave formwork is made up of base plate 21 and side wall 22, base plate 21 length 120mm, width 120mm, thickness m is 1mm, length direction side wall 22 length 110mm, width direction side wall 22 length 110mm, side wall 22 height 10mm, thickness n is 5mm, the distance l between the outer edge of the side wall 22 and the boundary of the bottom plate 21 is 5mm, and the depth s of the side wall 22 embedded in the bottom plate 21 is 0.5mm; b is 1 mm, and the perforation spacing c is 2.4 mm. The filler particles 1 are inserted into the perforations 3 from below the bottom plate 21 .

As shown in Figure 2, molten steel 4 is injected into the concave template 2 embedded with filling particles 1, so that the thickness of the molten steel layer is 0.6 mm. The molten steel is solidified to form a steel plate, and after the steel plate is cooled, the mold is demoulded, and the cooled steel plate is removed from the mold to obtain the target perforated steel plate.

Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or perform equivalent replacements for some of the technical features. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (5)

1. A method for manufacturing a micro-perforated metal plate is characterized in that liquid metal is injected into a mold assembled by two independent parts, namely a concave template and filling particles, and the micro-perforated metal plate with variable cross-section perforations is manufactured after solidification, cooling and demolding; the pore-forming aperture is controlled by adjusting the injection amount of the liquid metal or the size of the filling particles;

the concave template comprises a bottom plate and side walls which are embedded on the bottom plate and located on the periphery of the bottom plate, a plurality of platform-shaped through holes are formed in the bottom plate, the filling particles are embedded into the through holes and are cone-shaped or platform-shaped, and the horizontal cross section size of the tops of the particles is smaller than the aperture of the target micro-perforated metal plate through holes;

the filling particles are embedded into the through holes from the lower part of the bottom plate, the tops of the filling particles penetrate out of the upper surface of the bottom plate, the bottoms of the filling particles exceed the bottom of the bottom plate, and the openings at the upper parts of the through holes are tightly attached to the filling particles;

when the size of the die is fixed, increasing the injection amount of the liquid metal to increase the thickness of the liquid metal layer and reduce the pore diameter of the formed hole; when the thickness of the target micro-perforated metal plate is constant, the concave template is kept unchanged, the cone angle or the included angle between lateral edges of the filling particles is reduced, and the pore-forming aperture is reduced.

2. The method of claim 1, wherein the bottom of the filler particles is provided with a handle for easy gripping by a robot.

3. The method of claim 1, wherein the liquid metal is injected to a thickness less than the height of the filler particles protruding above the upper surface of the base plate.

4. The method of claim 1, wherein the filler particles and the concave form are made of a high temperature resistant material.

5. The method of claim 1, wherein the base plate and the sidewalls are integrally formed.

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