CN114656133B - An anti-viscosity and wear-reducing ultra-precision mold, processing system and method - Google Patents

Abstract

The invention belongs to the field of ultra-precision machining, and specifically proposes an anti-viscosity and wear-reducing ultra-precision mold, a processing system and a method. After obtaining a mold with an ultra-smooth surface using femtosecond laser processing technology, nano-texture is prepared on the surface of the mold by using femtosecond laser processing technology. Reduces mold-to-optical bonding and mold wear at high temperatures.

Description

An anti-viscosity and wear-reducing ultra-precision mold, processing system and method

technical field

The invention belongs to the field of ultra-precision machining, and in particular relates to an anti-viscosity and wear-reducing ultra-precision mold, a processing system and a method.

Background technique

Mold is an important basic process equipment in the manufacturing industry. It is mainly used for efficient mass production of related parts and components in industrial products, and is an important part of the equipment manufacturing industry. The mass-produced parts of the mold have the advantages of high efficiency, high consistency, low energy consumption, high precision and complexity, so they are widely used in machinery, electronics, automobiles, aviation, aerospace, military, medical, biological, energy, etc. and other industries. At present, the level of mold manufacturing has become an important symbol to measure the level of a country's manufacturing industry, and it is also one of the important guarantees for a country's industrial products to maintain international competitiveness.

Micro-complex structure devices, such as micro-complex structure optical elements, have a variety of optical functions due to their special geometric characteristics, which can realize functions that are difficult to be accomplished by traditional optical elements, and have important application value in the development of modern optical technology. At present, the manufacturing methods of micro-complex optical components are mainly based on single-point diamond cutting, photolithography and LIGA technology. Single-point diamond cutting has high machining accuracy, but because glass materials are brittle materials at room temperature, the feed rate of one cutting is very small, and the machining consistency is difficult to guarantee, which is not suitable for mass production; although lithography technology and LIGA technology It can complete micro-nano structure processing with small feature size and high surface quality, but this process is limited by production efficiency and process stability, and cannot well meet the needs of the industry.

The optical component molding technology has gradually gained attention in recent years. This technology refers to applying a certain pressure to the mold at high temperature to copy the specific structure of the mold surface to the surface of the optical component that is softened by heat, and then annealing, cooling and solidifying to obtain Ideal for miniature and complex optical components. This technology can realize high-volume and high-efficiency manufacturing of optical components. Since the removal of materials is not involved in the processing process, it can greatly reduce the consumption of raw materials and reduce manufacturing costs. It is considered to be one of the most effective methods for manufacturing optical components.

Among them, the compression molding technology is usually carried out at high temperature (500-1500 ℃). At present, since the surface shape accuracy and surface quality of optical components are determined by the mold, the existing molding process has high requirements on the surface quality of the mold. Smooth or ultra-smooth surface of any structure. However, the mold surface is prone to stick to the melted optical components at high temperature, thereby reducing the mold surface quality and service life, and increasing the production cost. In addition, under the action of heating-cooling temperature cycle and mold-clamping-release pressure cycle, the mold will experience thermal fatigue and stress fatigue, and the fatigue of mold material will easily cause mold wear and failure. The so-called mold wear refers to the normal dulling phenomenon of the working part of the mold due to high temperature and high pressure during the forming process. Mold breakage refers to the phenomenon that the mold is greatly deformed or the surface falls off, resulting in the phenomenon that the mold cannot be used normally. The mold damage is generally caused by the plastic flow of the microstructure caused by high temperature and high pressure, and the loss of forming ability.

At the same time, in recent years, high-temperature superhard materials such as tungsten carbide and silicon carbide have become the main materials for molds used in compression molding technology, but there are still many difficulties in the processing of superhard material molds. First, the efficiency of machining structure arrays on the surface of these hard materials by mechanical removal is very inefficient, and some structures cannot even be machined; secondly, due to the miniaturized size of microstructure arrays, once defects occur during the machining process, they cannot be repaired, and indirectly increase It reduces the manufacturing cost of micro-complex optical components.

SUMMARY OF THE INVENTION

Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide an anti-viscosity and wear-reducing ultra-precision mold, a processing system and a method.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

In the first aspect, the present invention provides an anti-viscosity and wear-reducing ultra-precision mold, the working surface of the mold is an ultra-smooth surface, and the ultra-smooth surface has nano-texture.

Compared with the conventional smooth or ultra-smooth mold with no defects or any texture on the surface, the present invention processes periodic or regularly arranged nano-textures on the surface of the ultra-smooth mold. Surface hardness, reducing the surface pressure of the mold, thereby improving the anti-sticking and anti-wear performance of the mold. The texture size proposed by the present invention is in nanometer order, and the optical element melted at high temperature cannot flow into the nanotexture due to the size effect, so the nanotexture on the surface of the ultra-smooth mold will not be transferred to the surface of the optical element, and the surface of the optical element cannot flow into the nanotexture due to the size effect. Quality and surface accuracy are not affected by nanotexturing.

As a further technical solution, when the working surface of the mold is a plane, the spacing of the nano-textures on the same surface is equal.

As a further technical solution, when the working surface of the mold is arc-shaped, the arcs of the nano-textures on the same working surface are equal.

As a further technical solution, the anti-viscosity and wear-reducing ultra-precision mold includes an upper mold and a lower mold, and the distance between the nano-textures on the working surface of the upper mold and the nano-textures on the working surface of the lower mold is equal.

As a further technical solution, a layer of film is also plated on the working surface of the anti-stick and wear-reducing ultra-precision mold.

In the second aspect, the present invention also provides a processing method of an anti-viscosity and wear-reducing ultra-precision mold, as follows:

Step 1 to obtain a mold with an ultra-smooth surface;

Step 2 Prepare nanotextures on the mold surface.

In a third aspect, the present invention also provides an ultra-precision mold for processing optical components, including an upper mold and a lower mold; the working surfaces of the upper mold and the lower mold are ultra-smooth surfaces, and the ultra-smooth surfaces The upper part has nano-texture; the lower mold is fixed on the heating cavity or in the heating cavity; the melting point of the mold is greater than the melting point of the optical element; the temperature in the heating cavity is greater than the melting point of the optical element and lower than the melting point of the mold.

In a fourth aspect, the present invention also provides a method for processing an optical element using the anti-viscosity and wear-reducing ultra-precision mold, as follows:

Fix the lower mold of the anti-viscosity and wear-reducing ultra-precision mold in the heating cavity;

Place the optical element to be processed above the lower mold;

Fix the upper mold of the anti-viscosity and wear-reducing ultra-precision mold above the optical element;

The heating chamber is heated, kept warm, and cooled to obtain an optical element.

In a fifth aspect, the present invention also provides a processing system for an anti-viscosity and wear-reducing ultra-precision mold, including a femtosecond laser, a spatial light modulator, a mirror, a dichroic mirror and an objective lens; the femtosecond laser is used for generating laser for processing; the spatial light modulator adjusts the light field, and the adjusted laser passes through the reflector, the dichroic mirror and the objective lens in sequence, and then acts on the surface of the processed mold, and the adjusted laser is applied to the surface of the processed mold. The surface forms nanotextures.

As a further technical solution, the processing system of the anti-viscosity and wear-reducing ultra-precision mold further includes a camera, which is arranged on one side of the dichroic mirror and is used to observe the surface morphology of the workpiece.

In the sixth aspect, a method for processing a periodic equal-arc-length nano-textured mold using the anti-viscosity and wear-reducing ultra-precision mold processing system is characterized in that: establishing a parametric equation of a complex curved surface and a corresponding coordinate system; determining a single The number of laser processing textures and the arc length between nano-textures; calculate the horizontal projection length of the arc length between two textures, substitute the projection length into the spatial light modulator, and adjust the femtosecond laser light field; use the adjustment After laser processing the curved mold, the periodic equal arc length nanotexture can be obtained.

The beneficial effects of the above embodiments of the present invention are as follows:

1. The present invention breaks the conventional mold design thinking. The present invention processes nano-texture on the ultra-smooth surface of the mold. Because the size of the nano-texture is extremely small, it can ensure that the processed element melted under high temperature conditions cannot flow into the size. In the smaller nano-texture, the nano-texture on the surface of the ultra-precision mold will not be transferred to the surface of the component, so that the molded component has high surface quality and surface accuracy.

2. The phenomenon of increased hardness will occur in the mold texture area of the present invention, so processing the nano texture will increase the hardness of the mold and improve its wear resistance; at the same time, the nano texture increases the force area of the mold and reduces the surface pressure of the mold. , which can improve the anti-adhesion ability of the mold and further improve its wear resistance.

3. The ultra-smooth surface and nano-texture composite optical mold processing method proposed by the present invention, after obtaining the mold with ultra-smooth surface through ultra-precision grinding and polishing technology, adopt femtosecond laser processing method or focus ion beam or electron beam in The nano-texture is prepared on the surface of the mold. On the premise of not affecting the performance of the mold and the surface quality and surface accuracy of the optical element after molding, the nano-texture is used to reduce the adhesion between the mold and the optical element and the wear of the mold under high temperature.

4. The equal arc length processing method proposed by the present invention can realize the processing of multiple array structures with uniform spacing on the surface of the curved mold at one time, greatly improve the processing efficiency of the texture, further improve the anti-sticking and wear-reducing performance of the mold surface, and extend the mold surface. service life.

5. The present invention proposes a nano-texture processing system on the surface of the mold. Through the directional modulation of the femtosecond laser spot by the spatial light modulator, nano-structures of various shapes and structures can be obtained on the surface of the mold, thereby realizing the extremely small surface of the mold. The efficient processing of the chemical structure reduces the production cost.

Description of drawings

The accompanying drawings, which form a part of the present invention, are used to provide a further understanding of the present invention, wherein the dimensions of the mold in the drawings are on the order of millimeters or more, and the nanotexture on the surface of the mold is only on the order of nanometers. The shape and structural characteristics of the nano-texture have been enlarged, and the actual nano-structure area (size) accounts for a very small proportion of the mold surface. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention.

1 is a schematic diagram of the anti-viscosity and wear-reducing ultra-precision mold of the trapezoidal cross-section disclosed in Example 1;

2 is a schematic diagram of an anti-viscosity and wear-reducing ultra-precision mold of triangular sawtooth cross-section disclosed in Example 1;

3 is a schematic diagram of the anti-viscosity and wear-reducing ultra-precision curved mold disclosed in Example 1;

Fig. 4 is the anti-stick and wear-reducing ultra-precision mold after coating disclosed in embodiment 1;

5 is a schematic diagram of the processing of the anti-viscosity and wear-reducing ultra-precision mold disclosed in Example 2;

6 is a schematic diagram of the molding process of the nano-textured curved surface mold disclosed in Example 3;

7 is a schematic diagram of the molding process of the nano-textured trapezoidal cross-section mold disclosed in Example 3;

8 is a schematic diagram of the molding process of the nano-textured triangular section mold disclosed in Example 3;

9 is a schematic diagram of the surface coating of the nano-textured mold disclosed in Example 3;

In the picture: 1 CCD camera, 2 mirrors, 3 femtosecond lasers, 4 spatial light modulators, 5 mirrors, 6 dichroic mirrors, 7 objective lenses, 8 nanostructures, 9 molds, 10 upper molds, 11 optical elements , 12 lower die, 13 coating.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the invention clearly dictates otherwise, the singular is intended to include the plural as well, and it is also to be understood that when the terms "comprising" and/or "including" are used in this specification, Indicate the presence of features, steps, operations, devices, components and/or combinations thereof;

Explanation of terms: in the present invention, the shape accuracy of the "ultra-precision mold" is sub-micron, and the surface roughness is ≤10 nm; the surface roughness of the "ultra-smooth surface" is ≤1 nm; class.

The nanotextures in the present invention can also be referred to as periodic nanostructures.

Example 1

In a typical embodiment of the present invention, as shown in FIG. 1 to FIG. 3 , this embodiment provides a variety of anti-viscosity and wear-reducing ultra-precision molds, the working surface of the mold is an ultra-smooth surface, and the ultra-smooth surface has nano Texture, in which the shape of the working surface can be either a plane or a curved surface. As shown in Figure 1, it is a schematic diagram of the anti-viscosity and wear-reducing ultra-precision mold with trapezoidal cross-section. There are several nano-textures in the form of circular pits; as shown in Figure 2, it is a schematic diagram of the anti-viscosity and wear-reducing ultra-precision mold with triangular sawtooth cross-section; on the working surface of the anti-viscosity and wear-reducing ultra-precision mold with triangular cross-section, there are a number of water droplets. As shown in Figure 3, Figure 3 is a schematic diagram of the anti-viscosity and wear-reducing ultra-precision curved mold; on the working surface of the anti-viscosity and wear-reducing ultra-precision ultra-precision mold, a number of nano-textures are processed.

The anti-stick and wear-reducing ultra-precision mold proposed in this embodiment breaks the conventional mold design idea. In the field of ultra-precision machining, in order to ensure the accuracy of the workpiece, the smoother the mold surface is generally required, and the present application breaks the conventional mold. The idea is to process the nano-texture on the ultra-smooth surface of the mold. Since the size of the nano-texture is extremely small, it can ensure that the processed components melted under high temperature conditions cannot flow into the smaller-sized nano-texture, so the ultra-precision The nano-texture of the mold surface will not be transferred to the component surface, so that the molded component has high surface quality and surface accuracy.

In this embodiment, the nano-texture area of the mold will increase the hardness, so processing the nano-texture will increase the hardness of the mold and improve its wear resistance; at the same time, the nano-texture increases the force-bearing area of the mold and reduces the surface of the mold. The pressure can improve the anti-adhesion ability of the mold and further improve its wear resistance.

In order to further exert the viscosity-reducing and anti-wear properties of nano-textures, the nano-textures on the workpiece surface need to maintain a uniform spacing; that is, when the working surface of the mold is flat, the nano-textures on the same surface have the same spacing, as shown in the figure As shown in Figure 1, the working surface is a plurality of planes with high and low settings. The spacing of nano-textures on the same plane is equal, and the spacing of nano-textures on different planes can be equal or unequal, depending on the actual processing requirements. Make settings. As shown in Figure 2, the working surface is a plurality of inclined planes, and the spacing of nanotextures on the same inclined plane is equal, and the spacing of nanotextures on different inclined planes can be equal or unequal; when the working surface of the mold is When it is a curved surface, the radians of the nano-textures on the entire working surface are equal. Specifically, as shown in Figure 3, the working surface of the mold is a continuous curved surface, and the radians of the nano-textures on the entire working surface are equal.

More specifically, the anti-viscosity and wear-reducing ultra-precision mold includes an upper mold and a lower mold. The distance between the nano-textures on the working surface of the upper mold and the nano-textures on the working surface of the lower mold is equal or different, depending on the actual needs. Just set it up.

Further, the materials of anti-sticking and anti-wear ultra-precision molds mainly include nickel-phosphorus alloy, glass carbon, silicon carbide, tungsten carbide, single crystal silicon, mold steel, quartz glass, copper-nickel alloy, polymethyl methacrylate, etc., among which , the surface roughness of the mold after ultra-precision grinding and polishing is less than or equal to 1nm.

Further, the nano-texture of the mold surface in this embodiment can be straight grooves, intersecting grooves, periodic circular pits, etc.; in the mold shown in FIG. The groove is formed by the intersection of two straight grooves in different directions. The periodic circular pit refers to the formation of multiple independent pits on the surface of the mold. The shape of the pit is semicircle, or hemisphere, arc, etc.; The specific dimensions of the groove, the general requirements are as follows:

Linear groove or cross groove-shaped nano-texture, the width of the groove is ≤ 100nm, the depth is ≤ 50 nm; the nano-texture of periodic circular pit shape, the diameter of the circular pit is ≤ 100 nm, and the depth is ≤ 50 nm; at the same time, in the straight line In the groove and periodic circular pit nanotexture, the distance between the groove and the circular pit can be 100-500 nm.

Further, the surface of the nano-textured mold working surface can also be coated, as shown in Figure 4, the coating can further improve the anti-sticking and wear-reducing performance of the mold, and at the same time, the textured surface can improve the mold surface and the coating material. strength, improve the coating effect. Specifically, the thickness of the coating can be 10-20 nm; the coating materials generally include three kinds, and one of the three materials can be selected, specifically including: (1) metal or precious metal alloy films, such as Pt-Ir, Ir- Re alloys; (2) ceramic films such as TaN, TiAIN and CrWN; (3) carbon-based films such as diamond-like carbon (DLC).

Example 2

The present embodiment also provides a method for processing an anti-viscosity and wear-reducing ultra-precision mold. In step 1, a mold with an ultra-smooth surface is obtained; in step 2, nano-texture is prepared on the surface of the mold; After obtaining a mold with an ultra-smooth surface, nanotextures are prepared on the surface of the mold by femtosecond laser processing or focused ion beam or electron beam.

Further, since the ultra-precision grinding and polishing methods are performed by using the existing processing methods, they will not be described in detail here.

Further, the above-mentioned femtosecond laser technology can process flat and curved molds; focused ion beam or electron beam mainly processes flat molds.

In this embodiment, the femtosecond laser processing method is mainly described. The processing system used in the femtosecond laser processing method is shown in FIG. 5, which includes a femtosecond laser 3, a spatial light modulator 4, a mirror 2, a mirror 5, The dichroic mirror 6 , the objective lens 7 and the CCD camera 1 are composed. The femtosecond laser 3 generates laser light for processing and enters the spatial light modulator 4, which can adjust the laser light field, and then the laser passes through the mirror 2, the mirror 5, the dichroic mirror 6 and the objective lens 7, and acts on the surface of the object , so as to realize the processing of the workpiece. By using the spatial light modulator 4 to modulate the laser amplitude, phase, polarization state, and coherence, light field distributions in various shapes such as parallel linear arrays, crossed linear arrays, and circular arrays can be obtained. When using the modulated laser to process the curved mold, compared with the single point or line-by-line groove processing in the traditional laser processing, the system can process multiple circular pits, linear grooves or intersecting grooves at one time. Nano-textures of different shapes greatly increase the processing area and improve the efficiency of laser processing.

The dichroic mirror 6 is used for spectral splitting, and can selectively transmit or reflect laser light of a certain wavelength. The wavelength of the femtosecond laser used in this system is 800 nanometers. In order to realize the functions of laser transmission and visible light reflection, a dichroic mirror 6 that can transmit wavelengths above 800 nm and cannot transmit wavelengths below 800 nm is selected.

The CCD camera 1 is used to observe the surface topography of the workpiece. The visible light on the surface of the object is reflected to the CCD camera 1 after passing through the dichroic mirror 6, which can realize the observation of the surface morphology of the workpiece before and after processing and during the processing, which is convenient for laser focusing and analysis of the surface morphology of the workpiece.

Femtosecond laser is used to process nano-texture on the surface of the mold, thereby improving the anti-adhesion and anti-wear properties of the mold. The spatial light modulator can change the distribution of the laser light field, so as to process multiple nano-textures of different shapes such as circular pits, straight grooves or cross grooves at one time.

In order to further exert the viscosity-reducing and anti-wear properties of nanotextures, the textures on the workpiece surface need to maintain a uniform spacing. By generating a periodic laser light field with a spatial light modulator, nanotextures with uniform pitch can be processed on the surfaces of trapezoidal cross-section molds and triangular cross-section molds. Due to the curvature of the circular-arc cross-section mold, the periodic light field generated by the spatial light modulator cannot process nanotextures with uniform spacing on its surface.

The following is a detailed description of the processing method of the arc-length periodic nanotexture on the surface of the curved mold, including the following steps:

First, establish the parametric equation of the complex surface and establish the corresponding coordinate system. The equation of the complex surface section is generally as follows:

（1）

(1)

In formula (1), R represents the vertex radius, and K represents the cone coefficient, both of which are intrinsic parameters of the surface mold.

Second, determine the number of textures processed by a single laser and the distance between the textures (ie arc length), as shown in Figure 4, so that the arc length l ₁ =l ₂ . Given l ₁ , find the length of the string ab, _ab , as follows:

（2）

(2)

（3）

(3)

In formulas (2) and (3), θ ₃ is the central angle corresponding to the arc ab, and r is the radius corresponding to the two points a and b. Since the distance between the arc lengths is in the order of nanometers, the two points correspond to each other in the calculation process. radii are approximately equal. The straight line ef is the tangent of the curved surface at point b, the slope of point b is derived from the formula (1), and θ ₂ is the angle between the straight line bd and the straight line be, which can be obtained by the following formula:

（4）

(4)

Therefore, the length of the straight line bd can be obtained, that is, the projection of the arc ab in the y direction, as shown in the following formula:

（5）

(5)

Similarly, the projection length d ₂ of arc bc in y can be obtained.

After completing the design of the type, quantity and interval of nanotextures on the surface of the curved mold, this method is used to calculate the projection length of the arc length between the two textures in the y direction, and the length is substituted into the spatial light modulator, and the The femtosecond laser light field is adjusted. Using the adjusted laser to process the curved mold, the periodic equal arc length nanotexture can be obtained.

Example 3

This embodiment provides a processing system and method for processing optical elements, and adopts the system and method for high-temperature compression molding to manufacture optical elements in batches, wherein the system includes the anti-viscosity and wear-reducing ultra-precision mold disclosed in Embodiment 1; More specifically, the processing system for processing optical elements includes an upper mold and a lower mold; the working surfaces of the upper mold and the lower mold are ultra-smooth surfaces, and the ultra-smooth surfaces have nano-textures; the lower mold is fixed on the heating cavity or In the heating cavity; the melting point of the mold is greater than the melting point of the optical element; the temperature in the heating cavity is greater than the melting point of the optical element and lower than the melting point of the mold. The specific structures of the upper mold and the lower mold are basically the same as those in Embodiment 1, and will not be repeated here.

The specific processing method is as follows:

First, fix the lower mold 12 with nanotexture in the high temperature heating cavity or on the heating cavity, then place the optical element 11 to be processed above it, and finally fix the upper mold 10 with nanotexture in the Above the optical element, after a series of operations such as heating, keeping warm, and cooling the heating chamber, an optical element of a certain shape and size can be obtained.

The melting point of the optical element 11 is different from that of the mold. During the compression molding process, the temperature in the heating cavity needs to be higher than the melting point of the optical element and lower than the melting point of the mold. During the molding process, the optical elements are softened by heat and the material flows to fill the specific structure of the mold. When filling, the material comes into contact with the surface of the mold. Under high temperature, reciprocation and surface interaction, the surface of the mold will be damaged by bonding and friction and wear, which will further affect the surface accuracy of the mold and the formed optical components. By processing nano-textures on the surface of the mold, including straight grooves, cross grooves and periodic circular pits, etc., the contact area between the material and the mold can be effectively increased, so that the pressure on the contact surface is reduced, thereby reducing the molding process. adhesion and mold wear. At the same time, the area where the nano-texture is processed on the surface of the mold will increase in hardness, thereby improving the surface hardness of the mold, which can further reduce the wear of the mold, prolong the life of the mold, and improve the production efficiency.

In this embodiment, the optical element melted at high temperature cannot be filled (flowed into) into the nano-texture of smaller size, so the optical element can only obtain a structure with a specific cross-section (trapezoid, triangular or other complex shape cross-section) through the molding technology , and the nanotexture of the ultra-smooth mold surface will not be transferred to the surface of the optical element, so the nanotexture will not affect the surface quality and surface accuracy of the optical element after molding.

In this embodiment, the materials of the upper mold 10 and the lower mold 12 mainly include nickel phosphorus alloy, glass carbon, silicon carbide, tungsten carbide, single crystal silicon, mold steel, quartz glass, copper-nickel alloy, polymethyl methacrylate Ester, etc., wherein the surface roughness of the mold after ultra-precision grinding and polishing is ≤1nm.

In this embodiment, the nano-textures on the surfaces of the upper mold 10 and the lower mold 12 mainly include linear grooves, intersecting grooves, periodic circular pits, and the like. Wherein, for the groove nanotexture, the width of the groove, the width of the groove is less than or equal to 100 nm, and the depth of the groove is less than or equal to 50 nm. Meanwhile, in the linear groove and periodic circular pit nanotextures, the groove and circular pit spacing can be 100-500 nm.

In this embodiment, the ion sputtering method is used to coat the surface of the nano-textured mold 13 , as shown in FIG. 9 ; the coating can further improve the anti-sticking and wear-reducing performance of the mold, and at the same time, the textured surface can improve the The bonding strength between the mold surface and the coating material improves the coating effect. Among them, the thickness of the coating is 10-20nm; the coating materials mainly include three kinds: (1) metal or precious metal alloy film, such as Pt-Ir, Ir-Re alloy; (2) ceramic film, such as TaN, TiAIN and CrWN; (3) Carbon-based films, such as diamond-like carbon (DLC), can be selected from one of the three materials.

The above processing method uses nano-texture to reduce the adhesion between the mold and the optical element and the wear of the mold under the premise of not affecting the performance of the mold and the surface quality and surface accuracy of the optical element after molding.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (7)

1. an anti-viscosity and wear-reducing ultra-precision mould is characterized in that, the working face of mould is an ultra-smooth surface, and on the described ultra-smooth surface, there is a periodic or regularly arranged nano-texture; The shape accuracy is sub-micron, and the surface roughness is less than or equal to 10 nm; the surface roughness of the ultra-smooth surface is less than or equal to 1 nm; the nano-texture refers to the size of the texture in the nano-scale; The nano-texture is linear groove, cross groove or periodic circular pit; the cross groove is formed by the intersection of two straight grooves in different directions, and the periodic circular pit refers to the formation of multiple independent pits on the surface of the mold. The shape of the pit is semicircle, or hemispherical, arc; the nanostructure of linear groove or cross groove, the width of the groove is ≤100nm, the depth is ≤50nm; the nanostructure of periodic circular pit shape, The diameter of the circular pit is ≤100nm, and the depth is ≤50nm; at the same time, in the linear groove and periodic circular pit nanotexture, the distance between the groove and the circular pit is 100-500nm; when the working surface of the mold is a plane, it is located on the same surface The spacing of the nano-textures on the upper mold is equal; when the working surface of the mold is a curved surface, the arc lengths of the nano-textures on the entire working surface are equal; the mold includes an upper mold and a lower mold, and the nano-texture on the working surface of the upper mold is the same as that of the lower mold. The spacing of the nanotextures on the working surface is equal. 2 . The anti-viscosity and wear-reducing ultra-precision mold as claimed in claim 1 , wherein a layer of film is also plated on the working surface of the mold. 3 . 3. a processing method of anti-viscosity and wear-reducing ultra-precision mould as claimed in claim 1, is characterized in that, Step 1 to obtain a mold with an ultra-smooth surface; Step 2 Prepare nanotextures on the mold surface. 4. An ultra-precision mold for processing optical components, characterized in that, the anti-viscosity and wear-reducing ultra-precision mold according to any one of claims 1-2 is adopted, comprising an upper mold and a lower mold; the upper mold, The working surface of the lower mold is an ultra-smooth surface, and the ultra-smooth surface has nano-texture; the lower mold is fixed on the heating cavity or in the heating cavity; the melting point of the mold is greater than the melting point of the optical element; The temperature is greater than the melting point of the optical element and less than the melting point of the mold. 5. utilize the method for ultra-precision mold processing optical element according to claim 4, it is characterized in that, Fixing the lower mold of the anti-viscosity and wear-reducing ultra-precision mold on the heating cavity or in the heating cavity; Place the optical element to be processed above the lower mold of the anti-viscosity and wear-reducing ultra-precision mold; Fixing the upper mold of the anti-viscosity and wear-reducing ultra-precision mold above the optical element; The heating chamber is heated, kept warm, and cooled to obtain an optical element. 6. the processing system of the anti-viscosity and wear-reducing ultra-precision mould as described in any one of claim 1-2, it is characterized in that: comprise femtosecond laser, spatial light modulator, reflecting mirror, dichroic mirror, objective lens and camera; The femtosecond laser generates laser light for processing; the spatial light modulator adjusts the light field, and the adjusted laser passes through the reflector, the dichroic mirror and the objective lens in sequence, and then acts on the processed laser. The surface of the mold forms nano-textures on the surface of the processed mold; the camera is arranged on one side of the dichroic mirror to observe the surface morphology of the workpiece. 7. Utilize the processing system of the anti-viscosity and wear-reducing ultra-precision mold of claim 6 to process the periodic equal-arc-length nano-textured mold, characterized in that: establish a parametric equation of complex curved surfaces and a corresponding coordinate system; determine a single The number of secondary laser processing textures and the arc length between nano-textures; the horizontal projection length of the arc length between the two textures is calculated, the projection length is substituted into the spatial light modulator, and the femtosecond laser light field is adjusted; using After the adjustment of the laser processing of the curved mold, the periodic equal arc length nanotexture can be obtained.

Images