Detection method and application of phase of refractory material

Abstract

The invention relates to the technical field of detection, in particular to a refractory material phase detection method and application, and the detection method comprises the following steps: cold embedding a sample to be detected by using a cold embedding material; carrying out grinding and polishing treatment; performing carbon spraying treatment to obtain a metallographic sample; s2, adjusting the scanning electron microscope to a high vacuum mode, setting an acquisition signal as a backscattered electron, and then detecting the metallographic sample to obtain a backscattered electron image; and carrying out EDS energy spectrum detection on microscopic structures with different gray levels in the scattered electron image to obtain chemical composition data, and / or carrying out EDS energy spectrum detection on microscopic structures with specific gray levels in the back scattered electron image to obtain chemical composition data corresponding to a specific object, and determining the object phase of the refractory material based on the chemical composition data. The detection method provided by the invention is not limited to solid blocky refractory materials, an ion sputtering instrument is not needed during sample pretreatment, and the cost is low.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of detection, in particular to a method for detecting the phase of refractory materials and application. BACKGROUND

[0002] In the process of steel smelting, various refractory materials are needed, especially in the process of special steel smelting, molten steel needs to be in contact with various refractory materials. Due to the scouring and peeling of molten steel, the whole refractory material falls into the molten steel, forming a large size of foreign inclusions, which is a physical process. The composition of the refractory material includes refractory material constituting oxides or nitrides, carbon and various binders and additives, and the composition elements of the refractory material dissolve into the molten steel to change the composition of the steel, which has a great impact on the quality of pure steel and ultra-pure steel, which is a physical and chemical process. In addition, the liquid phase formed at the interface between the refractory material and the molten steel can absorb the inclusions in the steel, thereby improving the quality of the steel.

[0003] Due to the above physical and chemical reactions, if the quality of the refractory material itself is poor or the operation in the smelting process is improper, a large amount of refractory material will be peeled off and enter the molten steel, and react with the high-temperature molten steel. If it is kept in the steel, it will form large non-metallic inclusions, which will seriously affect the purity of the steel. Therefore, it is necessary to analyze the phase of the refractory material before and after use to judge the phase change of the refractory material before and after use, so as to judge the quality of the refractory material, the operation and process of the smelting process, and indirectly improve the purity of the steel.

[0004] The detection in the prior art is mainly for the detection of the chemical composition and physical properties of the refractory material. The chemical composition mainly detects which elements are contained in the whole refractory material and the content of each element, but cannot determine the phase, such as whether the aluminum element in the refractory material is aluminum oxide, calcium aluminate or metallic aluminum. It cannot be distinguished by chemical composition, but only by phase detection. There are few reports on the detection of the phase of the refractory material in the prior art, and the detection in the prior art is limited to solid block refractory material. Ion sputtering instrument is needed for pretreatment of the sample, which is expensive.

[0005] Therefore, it is necessary to study a method for detecting the phase of the refractory material which is suitable for both solid block and powder refractory materials and has low cost, which is a technical problem to be solved in the field. SUMMARY

[0006] In view of the above problems in the prior art, the purpose of the present application is to provide a method for detecting the phase of refractory materials and application. The method for detecting the phase of the refractory material provided by the present application is not limited to solid block refractory material, and can be applied to both solid block and powder refractory material. Ion sputtering instrument is not needed for pretreatment of the sample, which is low in cost.

[0007] To achieve the above object, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a detection method of a refractory material phase, comprising the following steps:

[0009] S1, preparing a metallographic sample: using a cold mounting material to cold mount the sample to be measured; grinding and polishing the sample after mounting; spraying carbon on the surface of the sample after grinding and polishing to increase the electrical conductivity of the surface to be detected, thereby obtaining the metallographic sample;

[0010] S2, sample detection: adjusting the scanning electron microscope to high vacuum mode and setting the acquisition signal to backscattered electrons, then placing the metallographic sample in the scanning electron microscope for detection, obtaining the backscattered electron image of the surface to be detected, and distinguishing the phases according to the gray difference; using an energy spectrometer to perform EDS energy spectrum detection on the microstructure of different gray scales in the backscattered electron image, obtaining the chemical composition data corresponding to various phases, and / or using an energy spectrometer to perform EDS energy spectrum detection on the microstructure of a specific gray scale in the backscattered electron image, obtaining the chemical composition data corresponding to a specific phase, and determining the phase of the refractory material based on the chemical composition data.

[0011] Further, the cold mounting material comprises the following components by weight:

[0012]

[0013] Further, the nano-silicon dioxide includes hydrophobic nano-silicon dioxide; and / or the particle size of the hydrophobic nano-silicon dioxide is 20-100 nm;

[0014] And / or, the surfactant includes a fluorocarbon surfactant.

[0015] Further, the preparation method of the cold mounting material comprises the following steps:

[0016] Add the nano-silicon dioxide to the epoxy resin and ultrasonically disperse for 20-40 minutes;

[0017] Add the surfactant and then add the curing agent after high-speed stirring;

[0018] Vacuum degassing to obtain.

[0019] Further, the sample to be measured is in the form of a solid block or powder.

[0020] Further, the cold mounting of the sample to be measured using a cold mounting material comprises:

[0021] The sample to be detected is placed in a mold, then the cold inlay material is poured into the mold to immerse the sample to be detected, and finally, the cold inlay material is cured at room temperature and normal pressure.

[0022] Further, the grinding and polishing treatment of the inlaid sample includes grinding and polishing the surface to be detected of the inlaid sample by using an automatic grinding and polishing machine.

[0023] Further, the carbon spraying treatment of the surface to be detected of the sample after the grinding and polishing treatment includes:

[0024] The surface to be detected of the sample after the grinding and polishing treatment is placed upward in a vacuum chamber of a vacuum coating machine;

[0025] The vacuum chamber is covered, vacuumizing is started, and when the vacuum degree reaches 0.01-0.1 Pa, the carbon spraying treatment can be started.

[0026] Further, in step S1, the thickness of the carbon spraying layer is 10-30 nm.

[0027] And / or, the magnification of the scanning electron microscope is 200-2000 times.

[0028] And / or, the chemical composition data includes the types and weight percentage contents, atomic percentage contents of each element in the phase.

[0029] In a second aspect, the application provides an application of the detection method in the quality control of steel smelting refractory materials.

[0030] Compared with the prior art, the application has at least one of the following beneficial effects:

[0031] (1) The detection method of the refractory material phase provided by the application is not limited to solid block refractory materials, and can be applied to both solid block and powder refractory materials, and does not need to use an ion sputtering instrument for pretreatment of the sample, thereby reducing the cost.

[0032] (2) The cold inlay material is selected to perform cold inlay treatment on the sample, so that the pores of the refractory material are filled with the inlay material, and dust and other foreign matters will not pollute the scanning electron microscope during the subsequent vacuumizing process of the scanning electron microscope.

[0033] (3) The invention can make the subsequent observation more intuitive by carrying out metallographic sampling on the inlaid sample, and the surface of the metallographic sample after grinding and polishing is subjected to carbon spraying treatment, so that there is no charge accumulation phenomenon on the surface during subsequent observation, and the image effect is better; the average atomic number of different phases is different, and the corresponding color is different under the backscattered electron image, so under the high vacuum condition of the scanning electron microscope, the difference of different phases can be directly observed by using the backscattered image, and the phase can be quickly judged by combining the detection result of the energy spectrometer composition, and impurities and the like can also be found.

[0034] (4) The detection method provided by the invention can compare the micro changes of the refractory material before and after use, so as to judge the erosion of the refractory material in the smelting process.

[0035] (5) In the invention, the nano-silicon dioxide can reduce the viscosity of the cold inlay material and improve the permeability; the surfactant can promote exhaust and reduce the bubbles of the inlaid sample; the prior art relies on vacuum exhaust to eliminate bubbles, while the invention realizes defect-free inlaying under normal pressure by reducing the viscosity through nano fillers and self-exhausting through surfactants. The invention solves the problems of bubbles and permeability by synergistic effect of the formula components under the premise of canceling the vacuum step, and the effect is remarkable. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the specific embodiments of the invention or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the invention, and other drawings can also be obtained by those skilled in the art without creative labor.

[0037] Figure 1 It is a macroscopic morphology diagram of the sample after grinding and polishing in the embodiment 1 of the invention;

[0038] Figure 2 It is a backscattered electron image of the detection surface of the metallographic sample in the embodiment 1 of the invention;

[0039] Figure 3 It is a result diagram of the surface analysis of the sample by the energy spectrometer in the embodiment 1 of the invention;

[0040] Figure 4 It is a result diagram of the analysis of the phase of one color in the backscattered electron image by the energy spectrometer in the embodiment 1 of the invention;

[0041] Figure 5 It is a result diagram of the analysis of the impurity phase by the energy spectrometer in the embodiment 1 of the invention;

[0042] Figure 6A macro-morphology diagram of a sample in Example 2 of the present application;

[0043] Figure 7 A macro-morphology diagram of a sample after polishing in Example 2 of the present application;

[0044] Figure 8 A result diagram of surface analysis of a sample by an energy dispersive spectrometer in Example 2 of the present application;

[0045] Figure 9 A result diagram of analysis of a first color phase in a backscattered electron image by an energy dispersive spectrometer in Example 2 of the present application;

[0046] Figure 10 A result diagram of analysis of a second color phase in a backscattered electron image by an energy dispersive spectrometer in Example 2 of the present application;

[0047] Figure 11 A result diagram of analysis of a third color phase in a backscattered electron image by an energy dispersive spectrometer in Example 2 of the present application. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. It should be understood by those skilled in the art that the embodiments are only used to help understand the present application and should not be regarded as a specific limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application. The process parameters not specified in the following embodiments are usually according to the conventional conditions.

[0049] The endpoints of the ranges and any values disclosed in the present application are not to be construed as limiting. It is specifically intended that the description in the present application include all such closely related values. For numerical ranges, the endpoints are included in the ranges, and the endpoints and individual points are included in the ranges, and the individual points can be combined to form one or more new numerical ranges, which are to be construed as being specifically included in the present application.

[0050] In a first aspect, the present application provides a detection method of a refractory material phase, which comprises the following steps:

[0051] S1, preparing a metallographic sample: cold mounting the sample to be measured by using a cold mounting material; polishing the sample after mounting; and spraying carbon on the surface of the sample after polishing to increase the conductivity of the surface to be detected, so as to obtain the metallographic sample;

[0052] S2, sample detection: set the scanning electron microscope to high vacuum mode, set the acquisition signal to backscattered electrons, then place the metallographic sample in the scanning electron microscope for detection, obtain the backscattered electron image of the surface to be detected, and distinguish the phases according to the gray difference; use the energy spectrometer to perform EDS energy spectrum detection on the microstructure of different gray scales in the backscattered electron image, obtain the chemical composition data corresponding to various phases, and / or use the energy spectrometer to perform EDS energy spectrum detection on the microstructure of a specific gray scale in the backscattered electron image, obtain the chemical composition data corresponding to the specific phase, and determine the phase of the refractory material based on the chemical composition data.

[0053] The detection method of the phase of the refractory material provided by the application is not limited to solid block refractory materials, and can be applied to both solid block and powder refractory materials, does not need to use an ion sputtering instrument for pretreatment of the sample, has low cost, does not need to use a low vacuum mode for scanning electron microscope observation, and has high operation feasibility.

[0054] The sample is treated by cold inlaying with cold inlaying materials, so that the pores of the refractory material are filled with inlaying materials, and dust and other foreign matters are not introduced into the scanning electron microscope during subsequent vacuuming for scanning electron microscope observation.

[0055] The sample after inlaying is subjected to metallographic sample preparation, so that subsequent observation is more intuitive; the surface of the metallographic sample after grinding and polishing is subjected to carbon spraying treatment, so that there is no charge accumulation phenomenon on the surface during subsequent observation, and the image effect is better; the average atomic number corresponding to different phases is different, and the corresponding color in the backscattered electron image is different, so that the difference between different phases can be directly observed in the backscattered image under the high vacuum condition of the scanning electron microscope, the phase can be quickly judged by combining the detection result of the composition of the energy spectrometer, and impurities and the like can also be found.

[0056] By using the detection method provided by the application, the micro changes of the refractory material before and after use can be compared, so that the erosion of the refractory material in the smelting process can be judged.

[0057] In the detection method of the phase of the refractory material, as an optional implementation manner, the cold inlaying material comprises the following components in parts by weight:

[0058]

[0059] In the present application, the nano-silica can reduce the viscosity of the cold inlay material and improve the permeability; the surfactant can promote the exhaust and reduce the bubbles of the inlaid sample; the prior art relies on vacuum exhaust to eliminate bubbles, while the present application reduces the viscosity by nano-filler and self-exhausts by surfactant, so as to realize the defect-free inlay under normal pressure. Through the synergistic effect of the formula components, the present application solves the problems of bubbles and permeability under the premise of canceling the vacuum step, and the effect is remarkable.

[0060] In the detection method of the phase of the refractory material, as an optional embodiment, the nano-silica includes hydrophobic nano-silica.

[0061] In the detection method of the phase of the refractory material, as an optional embodiment, the particle size of the hydrophobic nano-silica is 20-100 nm, for example, it can be 20 nm, 40 nm, 60 nm, 80 nm or 100 nm.

[0062] In the detection method of the phase of the refractory material, as an optional embodiment, the surfactant includes a fluorocarbon surfactant.

[0063] In the detection method of the phase of the refractory material, as an optional embodiment, the preparation method of the cold inlay material includes the following steps:

[0064] The nano-silica (pretreated by silane coupling agent) is added to the epoxy resin, and ultrasonic dispersion is performed for 20-40 minutes;

[0065] The surfactant is added, and the curing agent is added after high-speed stirring;

[0066] Vacuum degassing is obtained.

[0067] In the detection method of the phase of the refractory material, as an optional embodiment, the sample to be detected is a solid block or a powder.

[0068] In the detection method of the phase of the refractory material, as an optional embodiment, the cold inlay of the sample to be detected by the cold inlay material includes:

[0069] The sample to be detected is placed in a mold, and then the cold inlay material is poured into the mold, so that the cold inlay material submerges the sample to be detected, and finally the cold inlay material is cured at room temperature and normal pressure (waiting for the cold inlay material to naturally cure).

[0070] In the detection method of the phase of the refractory material, as an optional embodiment, the grinding and polishing treatment of the inlaid sample includes: using an automatic grinding and polishing machine to grind and polish the detection surface of the inlaid sample.

[0071] In the detection method of the phase of the refractory material, as an optional implementation, the spraying carbon treatment is performed on the surface of the sample to be detected after the grinding and throwing treatment, and the spraying carbon treatment comprises:

[0072] The surface of the sample to be detected after the grinding and throwing treatment is placed upward in the vacuum chamber of the vacuum coating machine;

[0073] The vacuum chamber is covered, and vacuumization is started. When the vacuum degree reaches 0.01-0.1 Pa (for example, 0.01 Pa, 0.03 Pa, 0.05 Pa, 0.07 Pa or 0.1 Pa), the spraying carbon treatment can be started.

[0074] In the detection method of the phase of the refractory material, as an optional implementation, in step S1, the thickness of the spraying carbon layer is 10-30 nm (for example, 10 nm, 15 nm, 20 nm, 25 nm or 30 nm), which can improve the conductivity of the sample, and can improve the SEM signal acquisition rate. If the spraying carbon layer is too thin, the conductivity of the sample will be affected, the surface charge will be accumulated (charging effect) when the electron beam is bombarded, which will cause the image to twist and shake, the backscattered electron signal to drift, and the phase gray scale contrast to be distorted. If the spraying carbon layer is too thick, the backscattered electron signal will be weakened, and the resolution of the backscattered image will be reduced.

[0075] In the detection method of the phase of the refractory material, as an optional implementation, the magnification of the scanning electron microscope is 200-2000 times, for example, 2000 times, 500 times, 1000 times, 1500 times or 2000 times.

[0076] In the detection method of the phase of the refractory material, as an optional implementation, the chemical composition data comprises the types and weight percentage contents and atomic percentage contents of the elements in the phase.

[0077] In a second aspect, the application provides an application of the detection method in the quality control of the refractory material for steel smelting.

[0078] In the application, as an optional implementation, the application comprises:

[0079] The original sample before use and the residual sample after use of the same batch of refractory material are intercepted;

[0080] The phases of the original sample and the residual sample are detected by using the detection method of the first aspect;

[0081] The phase changes of the original sample and the residual sample are compared and analyzed, and based on the phase changes, the quality of the refractory material or the rationality of the smelting process is judged.

[0082] The application optimizes the performance of refractory materials and smelting process through phase change analysis before and after use, and indirectly improves the purity of steel.

[0083] The application will be further described in detail below in combination with specific examples and comparative examples.

[0084] In the following examples and comparative examples:

[0085] Epoxy resin: purchased from Shanghai Metallographic Mechanical Equipment Co., Ltd., epoxy resin part in cold inlay nest set;

[0086] Curing agent: purchased from Shanghai Metallographic Mechanical Equipment Co., Ltd., curing agent part in cold inlay nest set;

[0087] Hydrophobic nano-silica: commercially available product, from Nanjing Baokete New Material Co., Ltd., model PST-S05, primary particle size 20 nm.

[0088] Fluorocarbon surfactant: commercially available product, from Shenzhen Xinzhihexin Material Co., Ltd., brand FS-3100.

[0089] Example 1

[0090] A newly purchased ladle brick of a certain steel plant needs to understand its specific phase composition, and the detection method provided by the application is used for sample preparation and detection. The specific operation steps are as follows:

[0091] 1. Sample preparation (preparation of metallographic sample):

[0092] 1.1 Since the ladle brick is a large block of uniform material, a small block with a size of 20 mm can be obtained by random knocking;

[0093] 1.2 5 parts by weight of hydrophobic nano-silica is added to 100 parts by weight of epoxy resin, and ultrasonic dispersion is performed for 30 minutes; 0.5 parts by weight of fluorocarbon surfactant is added, and after high-speed stirring, 50 parts by weight of curing agent is added; vacuum degassing to obtain a cold inlay material;

[0094] 1.3 Select a thin-walled transparent PVC pipe as a mold, the PVC pipe wall thickness is 2 mm, the outer diameter is 30 mm, and a 20 mm long part can be cut; place the PVC pipe vertically on the paper board, and place the cut sample block to be detected downward in the PVC pipe;

[0095] 1.4 Pour the stirred cold inlay material into the PVC pipe, so that the cold inlay material submerges the test block;

[0096] 1.5 Stand and wait for the natural curing of the cold inlay material;

[0097] 1.6 directly use an automatic grinding and polishing machine to grind and polish the sample to be detected to a mirror surface, and the macroscopic morphology of the sample after grinding and polishing is shown inFigure 1 ;

[0098] 1.7 The metallographic sample is obtained by carbon spraying on the surface to be tested using a vacuum coating instrument to increase the conductivity of the surface to be tested. The carbon spraying process includes: placing the polished sample with the surface to be tested facing upwards in the vacuum chamber of the vacuum coating instrument; covering the vacuum chamber and starting to evacuate the vacuum. When the vacuum degree reaches 0.01 Pa, the carbon spraying process can be started. The thickness of the carbon sprayed layer is 20 nm.

[0099] 2. Sample testing:

[0100] 2.1 Set the scanning electron microscope to high vacuum mode, set the acquisition signal to backscattered electrons, select 20KV for the accelerating voltage, use a backscattered electron probe, and set the working distance to 10mm. Place the sample (metallographic sample) prepared in step 1 into the scanning electron microscope and use double-sided carbon conductive tape to bond the surface to be tested to the sample stage of the scanning electron microscope.

[0101] 2.2 The sample prepared in step 1 is directly observed using high vacuum mode to obtain a backscattered electron image of the surface to be tested. Because different substances in the refractory material have different average atomic numbers, they correspond to different colors in the backscattered electron image. Phases can be distinguished based on grayscale differences. Therefore, the differences between phases can be observed using the backscattered electron mode of a scanning electron microscope. See details... Figure 2 , Figure 2 This is a backscattered electron image of the surface to be tested on a metallographic sample, produced by... Figure 2 It can be seen that there are obvious color differences among different particles (phases) in this sample (metallographic sample);

[0102] 2.3 Surface analysis of the samples was performed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Specifically, EDS was used to detect the microstructure at different gray levels in the backscattered electron images to obtain the corresponding chemical composition data (type and weight percentage of each element in the phase, and atomic percentage content). The results are as follows: Figure 3 As shown, by Figure 3 It can be seen that the sample mainly contains aluminum oxide, and also contains silicon and titanium.

[0103] Local analysis of a phase of a specific color in a backscattered electron image is performed using an energy-dispersive X-ray spectroscopy (EDS) instrument. Specifically, EDS is used to detect the microstructure at a specific gray level in the backscattered electron image to obtain the corresponding chemical composition data (type, weight percentage, and atomic percentage of each element in the phase). The results are as follows: Figure 4 As shown, Figure 4 This is a magnified image of a backscattered electron image, showing the energy dispersive spectroscopy (EDS) analysis of one of the phases of a particular color. Figure 4 It can be determined that the phase is aluminum oxide.

[0104] 2.4At a higher magnification, the matrix and impurities in the refractory material can be observed. The microstructure at a specific gray level in the backscattered electron image is detected by EDS energy spectrum, and the chemical composition data (the type and weight percentage content, atomic percentage content of each element in the phase) of the impurity phase are obtained. The results are shown in Table 1. Figure 5 As shown in Table 1, the content of titanium element in the impurities is relatively high. Figure 5

[0105] Example 2

[0106] A tundish slag (tundish covering agent) used by a steelmaking plant needs to understand its specific phase composition. The sample is prepared and detected by the detection method provided by the application. The specific operation steps are as follows:

[0107] 1. Sample preparation (preparation of metallographic sample):

[0108] 1.1 Since the tundish slag is in a granular form, the size of a single particle is about 1 mm, and an appropriate amount of sample can be selected, as shown in FIG. 1. Figure 6

[0109] 1.2 7 parts by weight of hydrophobic nanosilica is added to 100 parts by weight of epoxy resin, and ultrasonic dispersion is performed for 30 minutes; 0.8 parts by weight of fluorocarbon surfactant is added, and after high-speed stirring, 50 parts by weight of a curing agent is added; vacuum degassing is performed to obtain a cold inlay material; then the tundish slag is added to the stirred cold inlay material, and continues to be stirred until the mixture is uniform.

[0110] 1.3 A thin-walled transparent PVC pipe is selected as a mold, the wall thickness of the PVC pipe is 2 mm, the outer diameter is 30 mm, and a 20 mm long pipe can be cut; the cold inlay material containing the sample after stirring is poured into the PVC pipe.

[0111] 1.4 Let stand and wait for the cold inlay material to naturally solidify.

[0112] 1.5 The surface to be detected of the solidified sample is directly polished to a mirror surface by using an automatic grinding and polishing machine, and the macroscopic morphology of the sample after polishing is shown in FIG. 2. Figure 7

[0113] 1.6 The surface to be detected is treated by carbon spraying through a vacuum coating instrument to increase the conductivity of the surface to be detected, and the metallographic sample is obtained. The carbon spraying treatment includes: placing the surface to be detected of the sample after polishing upward in the vacuum chamber of the vacuum coating instrument; cover the vacuum chamber, start vacuumizing, and when the vacuum degree reaches 0.03 Pa, the carbon spraying treatment can be started, and the thickness of the carbon spraying layer is 25 nm.

[0114] 2. Sample detection:

[0115] ​​​2.1 Set the scanning electron microscope to high vacuum mode, set the acquisition signal to backscattered electrons, select an acceleration voltage of 20 KV, use a backscattered electron probe, and set the working distance to 10 mm. Place the sample (metallographic sample) prepared in step 1 in the scanning electron microscope, and use double-sided carbon conductive tape to bond the surface to be detected to the sample stage of the scanning electron microscope;

[0116] 2.2 Directly observe the sample prepared in step 1 using high vacuum mode to obtain a backscattered electron image of the surface to be detected;

[0117] 2.3 Perform surface analysis of the sample using the scanning electron microscope energy spectrometer, i.e., use the energy spectrometer to perform EDS energy spectrum detection on the microstructure of different gray scales in the backscattered electron image to obtain chemical composition data (types and weight percentage contents, atomic percentage contents of elements in the phase) corresponding to various phases, as shown in Table 1. Figure 8 As can be seen from Table 1, the sample mainly contains silicon calcium magnesium aluminum oxides. Figure 8

[0118] 2.4 At a higher magnification, use the energy spectrometer to perform EDS energy spectrum detection on the microstructure of specific gray scales in the backscattered electron image to obtain chemical composition data (types and weight percentage contents, atomic percentage contents of elements in the phase) corresponding to a single phase, as shown in Table 2. Figures 9-11 As can be seen from Table 2, the sample mainly contains calcium silicate, magnesium oxide, and silicon oxide.

[0119] Comparative Example 1

[0120] The detection method provided in this comparative example is basically the same as in Example 1, except that the cold inlay material does not include hydrophobic nanosilica.

[0121] Comparative Example 2

[0122] The detection method provided in this comparative example is basically the same as in Example 1, except that the cold inlay material does not include fluorocarbon surfactant.

[0123] Comparative Example 3

[0124] The detection method provided in this comparative example is basically the same as in Example 1, except that the cold inlay material does not include hydrophobic nanosilica and fluorocarbon surfactant.

[0125] Performance Test

[0126] The viscosity and permeability of the cold inlay materials prepared in Examples 1-2 and Comparative Examples 1-3 were tested: the initial viscosity of the cold inlay material was measured using a rotational viscometer (25°C); the complete penetration time of the cold inlay material was observed through a porous sample (pore size 5-50 μm), and the results are shown in Table 1. ​

[0127] The number of bubble defects of the cold inlay materials prepared in Examples 1-2 and Comparative Examples 1-3 was counted: 50 groups of samples containing 1mm artificial pores were prepared, 10 groups of samples were cold inlaid with the cold inlay materials prepared in Examples 1-2 and Comparative Examples 1-3 respectively, and then polished and ground, the number of bubbles (diameter > 5μm) in the cross section was counted under a microscope, the average number of bubbles in the cross section was calculated, average number of bubbles = total number of bubbles / 10, and the results are shown in Table 1.

[0128] Table 1

[0129] Group Viscosity (mPa-s) Penetration time (min) Average number of bubbles per cross section Example 1 429 4 0.3 Example 2 467 5 0.5 Comparative Example 1 625 10 3.8 Comparative Example 2 552 8 5.6 Comparative Example 3 751 15 9.1

[0130] From Table 1, at least the following points can be seen:

[0131] (1) Comparing Example 1-2 with Comparative Example 1, when the cold inlay material does not include hydrophobic nanosilica, the viscosity of the cold inlay material increases, the penetration time increases, and the number of bubble defects increases. By limiting the cold inlay material to include hydrophobic nanosilica, the viscosity of the cold inlay material can be reduced, the permeability can be improved, and the number of bubble defects can be reduced.

[0132] (2) Comparing Example 1-2 with Comparative Example 2, when the cold inlay material does not include fluorocarbon surfactant, the number of bubble defects increases, and fluorocarbon surfactant can promote air exhaust and reduce the number of bubbles in the inlaid sample; the prior art relies on vacuum air exhaust to eliminate bubbles, while the present application reduces the viscosity by nanofiller and self-exhausts by surfactant to achieve defect-free inlaying under normal pressure.

[0133] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing examples, or make equivalent substitutions for part or all of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for detecting the phase composition of refractory materials, characterized in that, The detection method includes the following steps: S1. Preparation of metallographic sample: The sample to be tested is cold-mounted using a cold mounting material; the mounted sample is polished; the surface to be tested of the polished sample is carbon-sprayed to increase the conductivity of the surface to be tested, thereby obtaining the metallographic sample. S2. Sample Detection: The scanning electron microscope is set to high vacuum mode, and the acquisition signal is set to backscattered electrons. The metallographic sample is then placed in the scanning electron microscope for detection to obtain a backscattered electron image of the surface to be detected. The phases are distinguished based on the grayscale differences. The microstructures with different grayscale values ​​in the backscattered electron image are subjected to EDS energy dispersive spectroscopy to obtain the corresponding chemical composition data of each substance. And / or, the microstructures with specific grayscale values ​​in the backscattered electron image are subjected to EDS energy dispersive spectroscopy to obtain the corresponding chemical composition data of the specific substance. Based on the chemical composition data, the phases of the refractory material are determined.

2. The method for detecting the phase composition of refractory materials according to claim 1, characterized in that, The cold-mounting material comprises the following components in parts by weight:

3. The method for detecting the phase composition of refractory materials according to claim 2, characterized in that, The nano-silica includes hydrophobic nano-silica; and / or, the particle size of the hydrophobic nano-silica is 20-100 nm. And / or, the surfactant includes fluorocarbon surfactants.

4. The method for detecting the phase composition of refractory materials according to claim 2, characterized in that, The preparation method of the cold-mounting material includes the following steps: The nano-silica is added to the epoxy resin and ultrasonically dispersed for 20-40 minutes. Add the surfactant, stir at high speed, and then add the curing agent; Vacuum degassing yields the product.

5. The method for detecting the phase composition of refractory materials according to claim 1, characterized in that, The sample to be tested is in the form of a solid block or powder.

6. The method for detecting the phase composition of refractory materials according to claim 1, characterized in that, The process of cold-mounting the sample to be tested using a cold-mounting material includes: The sample to be tested is placed in a mold, and then the cold mounting material is poured into the mold to submerge the sample. Finally, the sample is allowed to stand and solidify at room temperature and pressure.

7. The method for detecting the phase composition of refractory materials according to claim 1, characterized in that, The polishing process for the inlaid sample includes: using an automatic polishing machine to polish the surface of the inlaid sample to be tested.

8. The method for detecting the phase composition of refractory materials according to claim 1, characterized in that, The process of carbon spraying the surface to be tested on the polished sample includes: Place the polished sample with the test surface facing upwards inside the vacuum chamber of the vacuum coating machine; Cover the vacuum chamber and begin evacuation. Once the vacuum level reaches 0.01-0.1 Pa, carbon spraying can begin.

9. The method for detecting the phase composition of refractory materials according to any one of claims 1-8, characterized in that, In step S1, the thickness of the carbon sprayed layer is 10–30 nm; And / or, the magnification of the scanning electron microscope is 200-2000 times; And / or, the chemical composition data includes the type and weight percentage content and atomic percentage content of each element in the phase.

10. The application of the detection method as described in any one of claims 1-9 in the quality control of refractory materials in iron and steel smelting.

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