[0036] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are only to enable the reader to have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be implemented even without these specific details.
[0037] High-temperature speckle needs to meet the following technical conditions: (1) It can withstand high enough temperature; (2) It has sufficient adhesion to the surface of the material, and will not fall off at high temperatures; (3) Ensure that it deforms simultaneously with the material. The speckle manufacturing methods in the prior art are either unable to withstand higher temperatures, or the manufacturing process is complicated, or the cost is high, and some manufacturing methods are inconvenient due to the long manufacturing cycle or the need for high-precision appliances and equipment. Promote use.
[0038] The invention uses low-cost, low-cost, widely sourced alumina and liquid binder as raw materials to produce speckles, reduces the production cost of speckles, and simplifies the production process of speckles; by using alumina as raw materials, the production of speckles is improved. High temperature stability of spots.
[0039] The technical solutions of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In order to deal with the problems of cumbersome manufacturing process, high cost, and small applicable temperature range of high-temperature speckles, the present invention provides an embodiment of a method for manufacturing speckles used in high-temperature deformation test experiments, such as figure 1 Shown.
[0040] According to the embodiment of the present invention, the flow of the method for manufacturing speckles used in the high-temperature deformation test experiment starts with step S1.
[0041] In step S1, ceramic powder with alumina as aggregate and liquid binder are selected as raw materials. Because these two kinds of raw materials are cheap and widely sourced, the production cost of high-temperature speckle can be greatly reduced. Alumina has a melting point of 2054°C, which can maintain stability at higher temperatures and is resistant to oxidation. Therefore, alumina is used as a raw material to improve the high-temperature stability of the produced speckles. According to a preferred embodiment of the present invention, the ceramic powder is alumina powder. The liquid binder is a binder that cures at high temperature. It is uniformly mixed with ceramic powder to make the prepared high-temperature speckles have sufficient adhesion. After verifying different tested samples, the temperature resistance of the speckle produced by the present invention mainly depends on the adhesion between the alumina and the tested sample, and can exist stably at a high temperature of 1800°C. After selecting the raw materials for making the speckles, in the embodiment of the present invention, the ceramic powder using alumina as the aggregate and the liquid binder are mixed in a mass ratio of 3:1. In order to mix the ceramic powder and the liquid binder sufficiently and uniformly, in the present invention, the mixed liquid obtained by mixing is also uniformly treated. If the frequency of ultrasonic cleaning is too small or the time of uniform treatment is too short, the ceramic powder and the liquid binder cannot be mixed sufficiently, agglomeration occurs, and the quality of speckles is affected. Preferably, an ultrasonic cleaning machine is used to uniformly treat the mixed liquid obtained by mixing, the frequency of the ultrasonic cleaning machine is 20 kHz, and the uniform processing time is not less than 20 minutes.
[0042] S2. Spray the uniformly treated mixture on the surface of the test sample.
[0043] If the surface of the tested sample is not flat, the surface of the tested sample will deform unevenly under high temperature conditions, thereby reducing the adhesion between the speckle and the surface of the tested sample. Therefore, according to a preferred embodiment of the present invention, before step S2, it further comprises: S0, cleaning and polishing the surface of the test sample. Preferably, after cleaning the tested sample, sandpaper is used to polish the surface of the tested sample, and alcohol is used to remove impurities on the surface of the tested sample. Then dry the tested sample for later use. The type and model of sandpaper can be determined according to the speckle size requirements of the test experiment. When using sandpaper to polish the surface of the test sample, one type of sandpaper can be used for polishing, or multiple types of sandpaper can be used for polishing, for example: first use coarser sandpaper for polishing, and then use finer sandpaper for polishing.
[0044] There are many ways to spray the uniformly processed mixture on the surface of the tested sample, for example: use the manufactured spray template to wrap the tested sample, and then apply the uniformly processed mixture on the spray template; It is also possible to spray the uniformly treated mixture directly on the surface of the sample to be tested by means of a spray pattern device. According to a preferred embodiment of the present invention, a brush is used to dip the uniformly treated mixture, and the brush is moved, and the uniformly treated mixture is splashed onto the surface of the test sample by inertia until a spot that meets the requirements is formed. The thickness and density of the brush can be determined according to the requirements of the test experiment on the size of the speckle, so that the size of the prepared speckle can be controlled. The smaller the speckle size, the finer the brush.
[0045] S3. Dry the test sample sprayed with the mixed liquid to obtain speckles on the surface of the test sample.
[0046] Preferably, step S3 is specifically: drying the sprayed sample to be tested naturally at room temperature for 2 hours, and after the speckle particles are initially stabilized and shaped, put them in a vacuum drying oven for 2 hours to thoroughly dry the speckles and set the shape under vacuum. The vacuum degree of the drying box is not more than 50Pa, and the temperature is 100°C.
[0047] figure 2 In order to use the production method of the present invention to produce a high-temperature speckle pattern on the surface of a carbon fiber composite material. In this embodiment, the sample to be tested is a carbon/carbon composite material, which adopts a four-way weaving form, that is, each layer is formed by laying and weaving three fiber bundles at an angle of 120° with each other, and the interlayer direction is reinforced by thick fibers. The high temperature speckle production process is as follows:
[0048] (1) After the surface of the tested sample is polished with 800 mesh and 1000 mesh sandpaper successively, clean the surface impurities of the tested sample with cotton swabs and alcohol, and place it to dry at room temperature;
[0049] (2) Weigh 30 grams of alumina powder and 10 grams of liquid binder by an electronic scale, put them into a beaker and stir evenly, then put the beaker into an ultrasonic cleaning machine for dispersion treatment, and take it out after 10 minutes;
[0050] (3) Use a 0.5-inch brush to dip in an appropriate amount of the prepared mixture and gently move it toward the surface of the sample until speckles that meet the requirements appear on the surface of the sample to be tested;
[0051] (4) Place the sprayed test sample horizontally at room temperature for 2 hours, let it dry naturally, and then put it in a vacuum drying oven for heating for 2 hours, and set the temperature to 100°C;
[0052] (5) Take it out and cool it naturally, and the speckle is finished.
[0053] Heat the prepared high-temperature speckle specimen to 1800℃, and the speckle appearance of the specimen surface under the infrared filter camera is like figure 2 As shown, the speckle in the figure is the size after magnification 10 times.
[0054] image 3 To use the manufacturing method of the present invention to make high-temperature speckle patterns on the surface of ultra-high-temperature ceramics. In this embodiment, the tested sample is an ultra-high temperature ceramic composite material, the main components are ZrB2, SiC and graphite, and the volume ratio of the three components is 13:4:3. The speckle production process is as follows:
[0055] (1) After the surface of the tested sample is polished with 800 mesh and 1000 mesh sandpaper successively, clean the surface impurities of the tested sample with cotton swabs and alcohol, and place it to dry at room temperature;
[0056] (2) Weigh 30 grams of alumina powder and 10 grams of liquid binder by an electronic scale, put them into a beaker and stir evenly, then put the beaker into an ultrasonic cleaning machine for dispersion treatment, and take it out after 10 minutes;
[0057] (3) Use a 0.5-inch brush to dip in an appropriate amount of the prepared mixture and gently move it toward the surface of the sample to be tested until speckles that meet the requirements appear on the surface of the sample to be tested;
[0058] (4) Place the sprayed test sample horizontally at room temperature for 2 hours, let it dry naturally, and then put it in a vacuum drying oven for heating for 2 hours, and set the temperature to 100°C;
[0059] (5) Take it out and cool it naturally, and the speckle is finished.
[0060] Heat the test sample prepared with high temperature speckle to 1800℃, and the surface speckle appearance of the test sample under the infrared filter camera is like image 3 As shown, the speckle in the figure is the size after magnification 10 times.
[0061] Figure 4 To use the production method of the present invention to produce high-temperature speckle patterns on the surface of high-strength graphite. In this embodiment, the sample to be tested is high-strength graphite, and the graphite material is easily volatilized when heated, which will have a certain influence on the surface speckle adhesion. The speckle production process is as follows:
[0062] (1) After the surface of the tested sample is polished with 800 mesh and 1000 mesh sandpaper successively, clean the surface impurities of the tested sample with cotton swabs and alcohol, and place it to dry at room temperature;
[0063] (2) Weigh 30 grams of alumina powder and 10 grams of liquid binder by an electronic scale, put them into a beaker and stir evenly, then put the beaker into an ultrasonic cleaning machine for dispersion treatment, and take it out after 10 minutes;
[0064] (3) Use a 0.5-inch brush to dip in an appropriate amount of the prepared mixture and gently move it toward the surface of the sample to be tested until speckles that meet the requirements appear on the surface of the sample to be tested;
[0065] (4) Place the sprayed test sample horizontally at room temperature for 2 hours, let it dry naturally, and then put it in a vacuum drying oven for heating for 2 hours, and set the temperature to 100°C;
[0066] (5) Take it out and cool it naturally, and the speckle is finished.
[0067] Heat the tested sample with high temperature speckles to 2000℃ step by step, Figure 4 Shown are the morphologies of speckles on the sample surface at 1800°C, 1900°C and 2000°C. It can be found that the volatility of graphite has a certain effect on the high temperature resistance of the speckles.
[0068] Compared with the prior art, the embodiment of the present invention uses low-cost, low-cost, widely sourced alumina and liquid binder as raw materials to produce speckles, which reduces the production cost of speckles and simplifies the production process of speckles; Alumina is used as a raw material to improve the high temperature stability of the produced speckles.
[0069] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be made. It is regarded as the protection scope of the present invention.