Silicon carbide ceramic optical mechanical structure and its manufacturing method and application

Abstract

The present invention relates to the technical field of silicon carbide ceramics, and discloses a silicon carbide ceramic optical mechanical structure and a manufacturing method and application thereof, wherein the manufacturing method comprises the following steps: constructing a preset model according to a designed silicon carbide ceramic optical mechanical structure; setting a cross section on the preset model, and splitting the preset model into a preset first part and a preset second part according to the cross section; completing the molding of the preset first part and the preset second part respectively to obtain a first part and a second part; obtaining raw material parameters of the silicon carbide ceramic optical mechanical structure, and preparing an adhesive according to the raw material parameters; using the adhesive to complete the bonding of the first part and the second part to obtain a blank; sintering the blank to obtain a silicon carbide ceramic optical mechanical structure. The present invention makes full use of the advantages of split molding and reaction sintering technology, realizes the efficient manufacturing of complex silicon carbide ceramic structures, and can ensure the density and mechanical properties of the structure.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon carbide ceramics, and in particular to a silicon carbide ceramic optical mechanical structure and a manufacturing method and application thereof. Background Art

[0002] Silicon carbide ceramics have good optical processing properties and can achieve excellent results through mechanical processing, making them widely used in optical reflectors and optical components. However, silicon carbide ceramic materials are relatively brittle, and direct processing with cutting tools is difficult, risky, and inefficient. At present, the production of high-precision silicon carbide ceramic structures mainly uses machine milling methods, but this method can only be used to produce simple silicon carbide ceramic structures, and it is difficult to achieve the production of complex silicon carbide ceramic structures. Summary of the invention

[0003] The present invention aims to improve at least one technical problem in the background technology.

[0004] A first aspect of the present invention provides a method for manufacturing a silicon carbide ceramic optical mechanical structure, comprising the following steps:

[0005] According to the designed silicon carbide ceramic optical mechanical structure, a preset model is constructed;

[0006] Setting a cross section on the preset model, and dividing the preset model into a preset first part and a preset second part according to the cross section;

[0007] Complete the molding of the preset first part and the preset second part respectively to obtain the first part and the second part;

[0008] Obtaining raw material parameters of the silicon carbide ceramic optical mechanical structure, and preparing an adhesive according to the raw material parameters;

[0009] Adhere the first part and the second part together by using the adhesive to obtain a blank;

[0010] Sintering the green body to obtain the silicon carbide ceramic optical mechanical structure;

[0011] The raw materials for preparing the adhesive include silicon carbide micropowder, silicon micropowder and carbon powder; the raw material parameters include the molar ratio of carbon element to silicon element in the silicon carbide ceramic optical mechanical structure raw material; the molar ratio of carbon element to silicon element in the raw materials for preparing the adhesive is the same as the molar ratio of carbon element to silicon element in the silicon carbide ceramic optical mechanical structure raw material.

[0012] The present invention splits the complex silicon carbide ceramic optical mechanical structure into two parts, and the two parts are separately molded. The molding methods include cold isostatic pressing combined with mechanical processing, dry pressing combined with mechanical processing, slip casting molding and gel casting molding. After the molding is completed, the two parts are bonded by a specific adhesive, and finally high-temperature reaction sintering is used to re-sinter the two parts into one, completing the production of the silicon carbide ceramic optical mechanical structure. Among them, the adhesive reacts with carbon and silicon under high temperature conditions in the subsequent sintering molding step to form silicon carbide. The reaction product is the same material as the raw material of the silicon carbide ceramic optical mechanical structure, so no impurities are introduced.

[0013] The beneficial effects of the present invention are as follows: the advantages of split molding and reaction sintering technology are fully utilized to achieve efficient manufacturing of complex silicon carbide ceramic structures, while ensuring the compactness and mechanical properties of the structure.

[0014] Furthermore, the cross section includes a plurality of regional solid surfaces, and the plurality of regional solid surfaces are all located on the same horizontal plane; the setting of the cross section satisfies the following conditions:

[0015] The cross section is arranged at a position close to the midline of the thickness direction of the preset model;

[0016] The area of ​​the solid surface of all the above mentioned areas shall not be less than 10mm 2 ;

[0017] The cross section intercepts the smallest area of ​​all holes in the preset model.

[0018] The cross section is set at the midline position close to the thickness direction of the preset model, which can ensure that the thickness of the first part and the second part are similar, and the deformation generated during sintering is similar, which is more conducive to subsequent bonding; if the area of ​​the solid surface of a certain area is less than 10mm 2 , the subsequent sintering and molding has a greater impact on this area, and the deformation caused makes it difficult to fit; the hole is the interface connecting the part with other workpieces, and is the most important feature to ensure the relative position of this structure with other structures. Once the hole feature is divided into two, there will be a slight difference in the thermal denaturation of the two parts during sintering. When it is finally sintered into a whole, the hole will deviate from the original expected position, and the cylindricity of the hole itself will also decrease. Therefore, not separating the hole in the cross section can ensure that the position and cylindricity of the hole are not affected or minimize the impact.

[0019] Furthermore, the distance between the cross section and the midline position in the thickness direction does not exceed 5 mm.

[0020] Furthermore, after the preset model is split, the thickness of the preset first part and the preset second part is not less than 15 mm. If the thickness of the preset first part and the preset second part is insufficient, they are easily deformed during the sintering process, making it difficult for the first part and the second part to fit completely together and difficult to form an integral body in the final sintering process.

[0021] Furthermore, when setting the cross section, the area of ​​the cross section is minimized while satisfying all setting conditions. Compared with other cross section setting situations, when the area of ​​the cross section is minimized, the deformation during sintering is smaller, and the performance of the silicon carbide ceramic optical mechanical structure finally obtained is better.

[0022] Furthermore, a fitting surface is formed on the first part and the second part respectively, and the fitting surface is formed by splitting the first part and the second part by a cross section, and the fitting surfaces are respectively ground.

[0023] Furthermore, after the grinding process, the flatness of the bonding surface is less than 0.008 mm. The grinding process can effectively reduce the roughness of the bonding surface and meet the high-precision requirements of flatness. The flatness of the bonding surface is less than 0.008 mm, which can ensure that the first part and the second part are flat, aligned and bonded during sintering.

[0024] Furthermore, the sintering temperature is 1600° C.-1700° C., the sintering time is 1 h-4 h, and the vacuum degree of the sintering does not exceed the saturated vapor pressure of silicon vapor.

[0025] A second aspect of the present invention provides a silicon carbide ceramic optomechanical structure, which is manufactured according to the above-mentioned manufacturing method.

[0026] A third aspect of the present invention provides the use of the above silicon carbide ceramic optomechanical structure as an optical element. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0028] Figure 1 Schematic diagram of the front and back structures of the silicon carbide ceramic optical mechanical structure of the embodiment;

[0029] Figure 2 Schematic diagram of the disassembly of the silicon carbide ceramic optical mechanical structure of the embodiment.

[0030] In the accompanying drawings: 1-first part; 2-second part; 3-fitting surface. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0034] Combine the following Figure 1 and Figure 2 Embodiments of the present invention are described.

[0035] The embodiment of the present invention provides a method for manufacturing a silicon carbide ceramic optical mechanical structure (especially a precision silicon carbide ceramic optical mechanical structure), comprising the following steps:

[0036] According to the designed (precision) silicon carbide ceramic optical mechanical structure (the silicon carbide ceramic optical mechanical structure of this embodiment is as follows Figure 1 As shown, Figure 1 a is the front side, b is the back side), and the preset model is constructed;

[0037] A cross section is set on the preset model, and the preset model is split into a preset first part and a preset second part according to the cross section;

[0038] The first part 1 and the second part 2 are respectively formed to obtain the first part 1 and the second part 2. The schematic diagrams of the first part 1 and the second part 2 are as shown in FIG. Figure 2 As shown;

[0039] Obtaining raw material parameters of the silicon carbide ceramic optical mechanical structure, and preparing an adhesive according to the raw material parameters;

[0040] Adhesive is used to bond the first part 1 and the second part 2 to obtain a blank;

[0041] The green body is sintered to obtain a (precision) silicon carbide ceramic optical mechanical structure;

[0042] The raw materials for preparing the adhesive include silicon carbide micropowder, silicon micropowder and carbon powder; the raw material parameters include the molar ratio of carbon element to silicon element in the raw material of silicon carbide ceramic optical mechanical structure; the molar ratio of carbon element to silicon element in the raw material of preparing the adhesive is the same as the molar ratio of carbon element to silicon element in the raw material of silicon carbide ceramic optical mechanical structure. Further, the cross section includes multiple regional solid surfaces, and the multiple regional solid surfaces are all located on the same horizontal plane; the setting of the cross section satisfies the following conditions:

[0043] The cross section is set at a midline position close to the thickness direction of the preset model;

[0044] The area of ​​all solid surfaces is not less than 10mm 2 ;

[0045] The cross section cuts into the smallest area of ​​all holes in the preset model.

[0046] The cross section of this embodiment is arranged at a position close to the midline position in the thickness direction of the preset model, and the spacing between the cross section and the midline position in the thickness direction is 1.2 mm. After the preset model is split, the thickness of the first part 1 formed is 17.8 mm, and the thickness of the second part 2 is 20.2 mm. The thickness of the first part 1 and the second part 2 are similar, and the deformation generated during sintering is similar, which is more conducive to subsequent bonding. In addition, the thickness of the first part 1 and the second part 2 are both greater than 15 mm, and the thickness is sufficient, so the deformation generated during sintering will not be too large to affect the bonding.

[0047] In this embodiment, the area of ​​the solid surface of all regions is higher than 10mm 2 The subsequent sintering molding has little effect on the solid surface of the region, and the resulting deformation does not affect its fitting.

[0048] Furthermore, when setting the cross section, the area of ​​the cross section is minimized while satisfying all setting conditions. Compared with other cross section setting situations, when the area of ​​the cross section is minimized, the deformation during sintering is smaller, and the performance of the (precision) silicon carbide ceramic optical mechanical structure obtained in the end is better.

[0049] Furthermore, the first part 1 and the second part 2 are respectively formed with a bonding surface 3, and the bonding surfaces 3 are respectively ground. After the grinding process in this embodiment, the flatness of the bonding surface 3 is 0.005 mm. In this embodiment, the roughness of the bonding surface 3 is effectively reduced by the grinding process, and the high-precision requirements of the flatness are met, and the flatness of the bonding surface 3 is ensured to enable the first part 1 and the second part 2 to be flat, aligned and bonded.

[0050] Furthermore, in this embodiment, the raw materials for preparing the adhesive include silicon carbide micropowder, silicon micropowder and carbon powder. In this embodiment, carbon and silicon react to form silicon carbide under high temperature conditions in the subsequent sintering molding step. The reaction product is the same material as the (precision) silicon carbide ceramic optical mechanical structure, so no impurities are introduced.

[0051] Furthermore, the molar ratio of carbon to silicon in the silicon carbide ceramic of this embodiment is 1.2:1, and the raw material ratio is controlled so that the molar ratio of carbon to silicon in the raw material for preparing the adhesive in this embodiment is 1.2:1.

[0052] Preferably, the sintering temperature is 1600° C., the sintering time is 2 hours, and the vacuum degree of the sintering does not exceed the saturated vapor pressure of silicon vapor.

[0053] In general, the method for manufacturing a (precision) silicon carbide ceramic optical mechanical structure provided in this embodiment splits the complex (precision) silicon carbide ceramic optical mechanical structure into two parts, and the two parts are separately molded by cold isostatic pressing combined with mechanical processing. After the molding is completed, the two parts are bonded by a specific adhesive, and finally high-temperature reaction sintering is used to re-sinter the two parts into one, completing the manufacturing of the (precision) silicon carbide ceramic optical mechanical structure. The present invention makes full use of the advantages of split molding and reaction sintering technology, realizes the efficient manufacturing of complex silicon carbide ceramic structures, and can ensure the density and mechanical properties of the structure.

[0054] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A method for manufacturing a silicon carbide ceramic optical mechanical structure, characterized in that: The following steps are involved: According to the designed silicon carbide ceramic optical mechanical structure, a preset model is constructed; Setting a cross section on the preset model, and dividing the preset model into a preset first part and a preset second part according to the cross section; Complete the molding of the preset first part and the preset second part respectively to obtain the first part and the second part; Obtaining raw material parameters of the silicon carbide ceramic optical mechanical structure, and preparing an adhesive according to the raw material parameters; Adhere the first part and the second part together by using the adhesive to obtain a blank; Sintering the green body to obtain the silicon carbide ceramic optical mechanical structure; The raw materials for preparing the adhesive are composed of silicon carbide micropowder, silicon micropowder and carbon powder; the raw material parameters include the molar ratio of carbon element to silicon element in the silicon carbide ceramic optical mechanical structure raw material; the molar ratio of carbon element to silicon element in the raw materials for preparing the adhesive is the same as the molar ratio of carbon element to silicon element in the silicon carbide ceramic optical mechanical structure raw material; The cross section includes a plurality of regional solid surfaces, and the plurality of regional solid surfaces are all located on the same horizontal plane; the cross section satisfies the following setting conditions: The cross section is arranged at a position close to the midline of the thickness direction of the preset model; The area of ​​the solid surface of all the above mentioned areas shall not be less than 10mm 2 ; The cross section intercepts the smallest area of ​​all holes in the preset model; The distance between the cross section and the midline position in the thickness direction does not exceed 5 mm; After the preset model is split, the thickness of the preset first part and the preset second part are not less than 15 mm; When setting the cross section, the area of ​​the cross section is minimized while satisfying the setting conditions.

2. The method for manufacturing a silicon carbide ceramic optical mechanical structure according to claim 1, characterized in that: The molding of the preset first part and the preset second part is completed respectively to obtain the first part and the second part, and the first part and the second part are respectively formed with a bonding surface, and the bonding surfaces are respectively ground.

3. The method for manufacturing a silicon carbide ceramic optical mechanical structure according to claim 2, characterized in that: After the grinding process, the flatness of the bonding surface is less than 0.008 mm.

4. The method for manufacturing a silicon carbide ceramic optical mechanical structure according to claim 1, characterized in that: The sintering temperature is 1600° C.-1700° C., and the sintering time is 1 h-4 h.

5. A silicon carbide ceramic optical mechanical structure, characterized in that: The silicon carbide ceramic optical mechanical structure is manufactured according to the manufacturing method according to any one of claims 1-4.

6. Use of the silicon carbide ceramic optical mechanical structure as claimed in claim 5 as an optical element.

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