A laser cutting method for ceramics that produces no microcracks and has a low incision roughness

Abstract

A laser cutting method for ceramics with no microcracks and low cut surface roughness. A phase change layer is provided on the ceramic surface. During the heating process of the laser, the heat absorption characteristic of the phase change layer during the phase change process reduces the thermal damage of the ceramic during processing, improves the stability of ceramic processing, makes it not easy to break, and greatly reduces the roughness of the cut surface during ceramic processing. And because the energy required for laser processing increases with the increase of the ceramic thickness, the thermal damage of the ceramic will intensify when processing thicker ceramics. The existence of the phase change layer increases the energy of the laser and increases the thickness of ceramic processing.

Description

Technical Field: The present invention relates to a ceramic cutting method, and particularly to a method for laser cutting ceramics. Background Art:

[0003] Currently, in the field of ceramic cutting, lasers have been used for cutting. More often, lasers are directly used to cut ceramics. Since ceramics have a certain brittleness, when processing ceramics with a thickness of more than 2 mm, direct laser cutting is prone to fracture and processing failure. Moreover, the laser absorption rate of ceramics is poor. In the direct laser cutting method, the cut surface of ceramic laser cutting is prone to thermal damage, resulting in a rough processing cross-section. Summary of the Invention:

[0005] The technical problem to be solved by the present invention is to provide a method for laser cutting ceramics to achieve laser cutting of ceramic products with various thicknesses, and the purpose of high yield and better cutting accuracy of the cut ceramics.

[0006] To solve the above technical problem, the technical solution of the present invention is:

[0007] A method for laser cutting ceramics: comprising the following steps:

[0008] Step 1: Select the area on the ceramic that needs to be laser cut;

[0009] Step 2: Add a phase change layer to the part that needs laser cutting;

[0010] Step 3: Turn on the laser and cut the pottery when the phase change layer changes from a solid state to a gaseous state.

[0011] As a preferred technical solution of the present invention; the phase change layer is composed of a base layer and a material layer. After heating the material layer from a solid state to a liquid state, it is evenly applied on the base layer and then cooled and dried.

[0012] As a preferred technical solution of the present invention: the material layer is: a solid paraffin layer, a refined paraffin layer or a microcrystalline wax layer, etc., and the base layer is a PET film, an ABS film, a PU film, etc.

[0013] As a preferred technical solution of the present invention; the base layer is a PET film, and the material layer is a refined paraffin layer. Place the refined paraffin in a crucible and change it from a solid state to a liquid state. After heating until it is completely changed from a solid state to a liquid state, place it in a drying and heat-insulating box and keep it for 10 - 30 minutes. Heat the PET film and the coater on a heating table. Pour the prepared liquid refined paraffin onto the coater and fully infiltrate the coater. Horizontally pull the coater from one end of the PET film to the other end of the PET film, and place the PET film horizontally in water to form a phase change layer.

[0014] As a preferred technical solution of the present invention; after heating the ceramic surface, the phase change layer is placed on the ceramic surface, the PET film is first covered on one side, then the other side is slowly put down, and then the material layer is attached to the ceramic. After the ceramic surface cools down, the PET film is removed, and a refined paraffin layer is formed on the ceramic surface.

[0015] As a preferred technical solution of the present invention; when the laser power is 1000 - 2000w, the frequency is increased by 100 - 200hz.

[0016] Due to the adoption of the above technical solution in the present invention, during the laser heating process, the heat absorption characteristic of the phase change layer during the phase change process reduces the thermal damage of the ceramic during processing. It improves the stability of ceramic processing, is not easy to break, greatly reduces the roughness of the cut during ceramic processing, and because the energy required for laser processing increases with the increase of the ceramic thickness, the thermal damage of the ceramic will intensify when processing thicker ceramics. The presence of the phase change layer increases the laser energy and increases the thickness of ceramic processing. Specific implementation method:

[0018] A method for laser cutting ceramics: includes the following steps:

[0019] Select the area on the ceramic that needs to be laser cut;

[0020] Add a phase change layer to the part that needs laser cutting; utilize the characteristic that the phase change material undergoes a phase change at a certain temperature. The phase change layer consists of a base layer and a material layer. The material layer is attached to the ceramic surface. The base layer uses a PET film. Since the PET film has the advantages of anti-static and anti-scratch, good adsorption, adhesion and polarity, and a relatively high melting point. It can prevent dust adsorption during the film production process and ensure the cleanliness of the film. It has good adsorption and adhesion, and can be well attached to the ceramic and the material layer. And it has a relatively high melting point and can be compatible with most phase change materials.

[0021] The material selected for the material layer needs to have characteristics such as stable physical and chemical properties, large latent heat of phase change, being solid at room temperature, and the solid-liquid phase change temperature being less than 150°C, etc. The material layer is: a solid paraffin layer, a refined paraffin layer or a microcrystalline wax layer, etc. The material of the base layer needs to have adsorption, polarity and a relatively high melting point. The base layer is a PET film, an ABS film, a PU film, etc.

[0022] The material layer is selected as a refined paraffin layer. When making the refined paraffin layer, first put the refined paraffin into a crucible and heat the crucible through a heating table to turn the refined paraffin from solid to liquid. During the heating process, do not use tools to stir, as bubbles will be generated during stirring, which will affect the quality of the refined paraffin layer. The heating temperature can be 30°C higher than the phase change temperature. After heating until it is completely changed from solid to liquid and there are no obvious particles, place it in a drying and insulation box and keep it for 20 minutes to volatilize the moisture in the refined paraffin. Then it can be used. If there is too much residual moisture in the material, it will affect the quality of the refined paraffin layer.

[0023] After the refined paraffin layer is heated to a liquid state, heat the PET film and the coater on the heating table, and set the temperature 5°C higher than the phase change temperature. This is beneficial to reducing the fluidity of the refined paraffin layer and facilitating subsequent cooling to form a film. Pour the prepared liquid refined paraffin onto the coater and fully wet the coater. Pull the coater horizontally from one end of the PET film to the other end of the PET film to obtain a liquid film with uniform thickness. Place the PET film horizontally in pure water at a temperature 40 - 50°C lower than the phase change temperature. The specific heat capacity of pure water is relatively large, which can quickly cool down and prevent the phase change film from cracking due to too rapid cooling, and make the phase change material solidify quickly to form a solid refined paraffin layer with uniform thickness.

[0024] After the refined paraffin layer is made, heat the ceramic to be cut through a wafer heating table until the surface temperature is 5°C higher than the phase change temperature, so as to make the ceramic surface temperature uniform.

[0025] Place the phase change layer on the ceramic surface so that the PET film fits the ceramic surface. The PET film is covered with one side first, and then the other side is slowly put down to prevent bubbles from generating inside. After pasting the film, let it stand still, and use the gravity of the PET film to force the film to evenly fill the ceramic surface. Under the heating state, due to the strong polarity of the PET film, the adhesion between the refined paraffin layer and the PET film and the adhesion between the refined paraffin layer and the ceramic, the refined paraffin layer will separate from the PET film. After cooling, remove the PET film, and a refined paraffin layer is formed on the ceramic surface.

[0026] Turn on the laser to cut the pottery when the phase change layer changes from solid to gaseous state.

[0027] After placing the phase change layer on the ceramic surface, perform laser processing according to normal parameters. Due to the existence of the phase change layer on the ceramic surface, during the laser processing, the phase change layer on the ceramic surface undergoes a phase change, and the refined paraffin layer changes from solid to gaseous state, taking away a large amount of heat, which can reduce the heat accumulation on the ceramic surface and reduce the generation of microcracks on the ceramic surface. At the same time, the laser processing power can be increased. The power is increased from the original 1000w to 1500w, and the laser processing frequency can be increased by 100 - 200hz, which can make the ceramic withstand a more intensive punching frequency and improve the processing accuracy.

[0028] Meanwhile, the characteristic of the phase change layer absorbing heat during the laser processing effectively improves the thermal effect. At the same time, the phase change layer has the characteristic of being solid at normal temperature and is easy to form a uniform protective film on the ceramic surface. If, during the processing, the material layer changes from solid to liquid, the processing must be stopped immediately because of the heat accumulation on the ceramic surface, and the laser power parameters need to be adjusted.

Claims

1. A method for laser cutting ceramics, characterized in that: It includes the following steps: Step 1: Select the area on the ceramic that needs to be laser cut; Step 2: Add a phase change layer to the part that needs to be laser cut; Step 3: Turn on the laser and cut the ceramic when the phase change layer changes from solid state to gaseous state; The phase change layer is composed of a base layer and a material layer. After heating the material layer from solid state to liquid state, it is evenly applied on the base layer and then cooled and dried; The base layer is a PET film, and the material layer is a refined paraffin layer. Place the refined paraffin in a crucible and change it from solid state to liquid state. Heat it until it completely changes from solid state to liquid state, then put it in a drying and heat preservation box and keep it for 10 - 30 minutes. Heat the PET film and the coater on a heating table. Pour the prepared liquid refined paraffin onto the coater to fully wet the coater, horizontally pull the coater from one end of the PET film to the other end, and place the PET film horizontally in water to form a phase change layer.

2. The method for laser cutting ceramics according to claim 1, characterized in that: After heating the ceramic surface, place the phase change layer on the ceramic surface. First cover one side with the PET film, then slowly put down the other side, and then the material layer adheres to the ceramic. After the ceramic surface cools down, remove the PET film, and a refined paraffin layer is formed on the ceramic surface.

3. The method for laser cutting ceramics according to claim 1 or 2, characterized in that: The power of the laser is 1000 - 2000w, and the frequency is increased by 100 - 200hz.