阅读说明：本技术 一种3d打印织构化自润滑陶瓷材料的方法 (Method for 3D printing of textured self-lubricating ceramic material ) 是由 梅辉 赵钰 孔紫嫣 成来飞 张立同 于 2019-11-18 设计创作，主要内容包括：本发明涉及一种3D打印织构化自润滑陶瓷材料的方法,使用绘图软件绘制不同表面织构的三维模型图,然后采用3D打印技术打印出具有表面织构的陶瓷前驱体,根据自润滑陶瓷材料的特点采用高温烧结后,再在表面搭载润滑剂实现结构和润滑的协同作用。通过3D打印技术精确控制表面织构的形貌等几何参数,便于实现结构与润滑剂的协同效应。本发明结构设计灵活,表面结构与材料制备可一次成型,工艺过程操作简单,可重复性高,耗时短、成本低,适用于Al<Sub>2</Sub>O<Sub>3</Sub>、ZrO<Sub>2</Sub>、SiO<Sub>2</Sub>等陶瓷材料的打印。3D打印织构化自润滑陶瓷材料应用于航空航天高温滑动密封系统。(The invention relates to a method for 3D printing of a textured self-lubricating ceramic material, which comprises the steps of drawing three-dimensional model diagrams with different surface textures by using drawing software, then printing a ceramic precursor with the surface textures by adopting a 3D printing technology, carrying a lubricant on the surface after high-temperature sintering according to the characteristics of the self-lubricating ceramic material to realize the synergistic effect of structure and lubrication. By passingThe 3D printing technology accurately controls geometric parameters such as the appearance of the surface texture and the like, and is convenient for realizing the synergistic effect of the structure and the lubricant. The invention has flexible structure design, one-step molding of surface structure and material preparation, simple operation of technological process, high repeatability, short time consumption and low cost, and is suitable for Al 2 O 3 、ZrO 2 、SiO 2 And the like. The 3D printing textured self-lubricating ceramic material is applied to aerospace high-temperature sliding sealing systems.)

1. A method for 3D printing of a textured self-lubricating ceramic material is characterized by comprising the following steps:

step 1, designing and drawing a surface texture: designing surface textures with different geometric parameters, drawing a three-dimensional model by adopting SolidWorks drawing software, and storing the three-dimensional model as an STL format file;

step 2, computer slicing treatment: opening the STL format file formed in the step 1 in slicing software, adjusting the position and the scaling size of the three-dimensional model on a platform, setting the layer thickness of a printing material to be 55 microns and the layer number of a bottom plate to be 5 layers, and obtaining a sliced file;

step 3, 3D printing: copying the cut file to a 3D printer, and printing ceramic preforms with different surface textures by using ceramic slurry;

and 4, high-temperature sintering: sintering the obtained ceramic preform in a box furnace, keeping the temperature for 2 hours when the temperature is raised to 300 ℃, 600 ℃ and 900 ℃, keeping the temperature for 3 hours when the temperature is raised to 1500 ℃, and then cooling to room temperature;

and step 5, carrying a lubricant: carrying a solid lubricant WS on a high-temperature sintered ceramic preform with different surface textures by hydrothermal treatment₂The hydrothermal reaction is heated from room temperature to 200 ℃ at a heating rate of 3 ℃/min and then is kept for 24 hours.

Technical Field

The invention belongs to printing of self-lubricating ceramic materials, and relates to a method for 3D printing of textured self-lubricating ceramic materials.

Background

As a self-lubricating material with great development prospect, the ceramic material has the characteristics of high strength, high hardness, low density, excellent wear resistance, corrosion resistance and high temperature resistance, and is the best candidate material for realizing ultrahigh-temperature sliding seal in the aerospace field. However, the most prominent problem of ceramic materials is that the friction coefficient and the wear rate are high at high temperature, so that an effective friction-reducing and wear-resisting method is needed to improve the high-temperature tribological performance. At present, theoretical research and engineering practice of a plurality of scholars show that: the smoother the friction surface, the better, the too smooth surface can not effectively bear the lubricant, and the poor quality of the lubricating film formed between the two surfaces is not beneficial to lubrication; the surface of the friction pair with certain surface roughness and microcosmic geometric morphology can well store the lubricant and reduce the contact area between the friction pair, thereby achieving the purpose of lubrication.

The surface texture technology is to process a surface micro-shape with certain shape, size and arrangement on the surface of a friction pair, and becomes an effective means for improving the lubricating performance. The main processing methods include Laser Surface Texture (LST), surface laser shot peening (LPT), Lithography (LIGA), Reactive Ion Etching (RIE), embossing technology, electric spark processing, electric machining and the like. The laser surface texture is widely used with the advantages of relatively high precision, universality, flexibility and no pollution, but has the problems that the microstructure and mechanical properties of the material are changed due to the fact that a high-energy laser beam irradiates the surface of the material to be instantly melted and gasified to generate a heat affected zone on the surface of a workpiece, bulges, burrs and the like easily occur near the texture, secondary processing is needed, energy consumption is high, the preparation efficiency is reduced, only simple geometric patterns can be processed, and the processing control of complex and bionic patterns is difficult; the surface laser shot blasting treatment has great environmental pollution, difficult control and low precision; the photoetching technology has high processing cost; the reactive ion etching technology needs an auxiliary device or a special environment; the embossing technology has complex process and high cost; the electric spark machining technology has high consumption and high cost. For example, chinese patent CN 201711395150.7 discloses a method for preparing a vacuum plasma self-lubricating coating on a laser micro-texture surface, which comprises processing a circular pit micro-texture on a metal surface by laser scanning, and spraying a NiAlMo bonding layer on the surface to reduce the friction coefficient and wear loss of the metal surface; chinese patent CN 201710091779.6 discloses a preparation method of a micro-texture self-lubricating ceramic guide rail, which adopts femtosecond laser processing technology to process micropores on the surface of ceramic, and then fills a solid lubricant. In the existing surface texture processing technology, the defects that the designed and processed surface texture is single, is limited to simple geometric patterns, has low processing precision, is easy to generate bulges and burrs, and has high energy consumption, high cost, low processing efficiency and the like exist.

The 3D printing technology is used as one additive manufacturing technology, the point, the line or the surface is used as a basic unit to carry out layer-by-layer accumulation manufacturing, the rapid forming of a complex structure which cannot be achieved or is difficult to achieve by a traditional method can be realized, and the method has the advantages of simplicity and convenience in operation, low production cost, short period, flexible structural design and the like. Therefore, the 3D printing micro-texture technology is combined with the ceramic material, and the integration of material preparation and texture is realized, so that the purpose of ultra-high temperature lubrication is achieved. Chinese patent CN201710927442.4 discloses a 3D printing method for making micro texture on the surface of a friction pair, but the method is to introduce the designed three-dimensional model into a robot control device, and perform laser sintering treatment on the surface of the friction pair, and adopts a selective laser sintering technology.

Disclosure of Invention

Technical problem to be solved

In order to avoid the defects of the prior art and aim at the technical defects of the prior art, the invention provides a method for 3D printing of a textured self-lubricating ceramic material, which is used for preparing the textured self-lubricating ceramic material by utilizing the current high-precision 3D printing photocuring technology. The method aims to accurately control geometric parameters such as the appearance of the surface texture and the like through a 3D printing technology, and is convenient for realizing the synergistic effect of the structure and the lubricant. The idea of the invention is to use drawing software to draw three-dimensional model diagrams with different surface textures, then to print out a ceramic precursor with the surface textures by adopting a 3D printing technology, and to carry a lubricant on the surface after high-temperature sintering to realize the synergistic effect of structure and lubrication.

Technical scheme

Step 1, designing and drawing a surface texture: designing surface textures with different geometric parameters, drawing a three-dimensional model by adopting SolidWorks drawing software, and storing the three-dimensional model as an STL format file;

step 2, computer slicing treatment: opening the STL format file formed in the step 1 in slicing software, adjusting the position and the scaling size of the three-dimensional model on a platform, setting the layer thickness of a printing material to be 55 microns and the layer number of a bottom plate to be 5 layers, and obtaining a sliced file;

step 3, 3D printing: copying the cut file to a 3D printer, and printing ceramic preforms with different surface textures by using ceramic slurry;

and 4, high-temperature sintering: sintering the obtained ceramic preform in a box furnace, keeping the temperature for 2 hours when the temperature is raised to 300 ℃, 600 ℃ and 900 ℃, keeping the temperature for 3 hours when the temperature is raised to 1500 ℃, and then cooling to room temperature;

and step 5, carrying a lubricant: carrying a solid lubricant WS on a high-temperature sintered ceramic preform with different surface textures by hydrothermal treatment₂The hydrothermal reaction is heated from room temperature to 200 ℃ at a heating rate of 3 ℃/min and then is kept for 24 hours.

Advantageous effects

The invention provides a method for 3D printing of textured self-lubricating ceramic material, which comprises the steps of drawing three-dimensional model diagrams with different surface textures by using drawing software, printing a ceramic precursor with the surface textures by adopting a 3D printing technology, carrying a lubricant on the surface after high-temperature sintering according to the characteristics of the self-lubricating ceramic material to realize the synergy of structure and lubricationAnd (4) acting. Geometric parameters such as the appearance of the surface texture and the like are accurately controlled through a 3D printing technology, and the synergistic effect of the structure and the lubricant is convenient to realize. The invention has flexible structure design, one-step molding of surface structure and material preparation, simple operation of technological process, high repeatability, short time consumption and low cost, and is suitable for Al₂O₃、ZrO₂、SiO₂And the like. The 3D printing textured self-lubricating ceramic material is applied to aerospace high-temperature sliding sealing systems.

The invention has the following beneficial effects:

1. the surface texture can be flexibly designed, and geometric parameters such as the shape, the size, the area density, the depth-diameter ratio and the like of the surface texture can be accurately controlled, so that the texture with the optimal lubricating effect can be selected.

2. The integration and rapid molding of the ceramic material and the texture can be realized by adopting a 3D printing technology, the technological process is simple to operate, the repeatability is high, the time consumption is short, the cost is low, and the preparation efficiency can be improved.

3. The method is suitable for Al₂O₃、ZrO₂、SiO₂And the application range is wide when the ceramic material is printed. The friction and wear performance test is carried out on the prepared 3D printing textured self-lubricating ceramic material, and the result shows that the Al without the 3D printing surface texture₂O₃The friction coefficient of the ceramic material is 1.006, and the Al has surface texture₂O₃The friction coefficient of the ceramic material can be reduced to 0.441 at the lowest, which is reduced by 56.16%.

Drawings

FIG. 1: 3D printed texture design drawing of the invention

(a) Round petal-shaped densely-arranged surface textures with the hemisphere diameter of 2.5 mm; (b) the surface texture is arranged in a round petal-shaped hexagon with the hemisphere diameter of 2.5 mm; (c) round petal-shaped densely-arranged surface textures with the hemisphere diameter of 5 mm; (d) the surface texture is arranged in a round petal-shaped hexagon shape with the hemisphere diameter of 5 mm;

FIG. 2: 3D printing of Al with different surface textures in embodiment 1, embodiment 2, embodiment 3 and embodiment 4 of the invention₂O₃Ceramic materialFigure (a).

FIG. 3: carrying solid lubricant WS₂SEM image of (d).

Detailed Description

The invention will now be further described with reference to the following examples and drawings: