High-entropy oxide glass and preparation method thereof

Abstract

The invention discloses a preparation method of high-entropy oxide glass, which comprises the following steps: weighing metal oxide powder in a set proportion to obtain glass raw material powder which comprises at least five metal oxides; grinding and drying the glass raw material powder for multiple times to obtain mixed powder; the mixed powder is pressed and formed and then subjected to presintering treatment, and an initial sample wafer is obtained; crushing the initial sample to obtain a plurality of sample blocks; the sample block is placed in a suspension furnace, a nozzle is arranged at the bottom of the suspension furnace, and the nozzle is used for spraying gas with a set flow into the suspension furnace to enable the sample block to suspend in the suspension furnace; a plurality of laser sources are adopted to heat the sample block, the plurality of laser sources form a plurality of light spots on the surface of the sample block, and a gap is formed between any adjacent light spots, so that the sample block is completely fused to form a fused sphere; and quickly cooling the molten spheres to prepare the high-entropy oxide glass. The invention also discloses the high-entropy oxide glass.

Description

Technical Field

[0001] The present invention relates to the technical field of oxide glass materials, and in particular to a high-entropy oxide glass and a preparation method thereof. Background Art

[0002] Currently, with the continuous development of intelligent devices and the emergence of emerging technologies such as folding screens and flexible screens, the requirements for display glass in terms of strength, ultra-thinness, flexibility, and light transmittance have become increasingly stringent. Improving the hardness and Young's modulus of glass can effectively improve the drop resistance and wear resistance of the screens of intelligent devices. Therefore, the research on high-performance optical glass with both high hardness and high Young's modulus is of great significance.

[0003] High-entropy materials have received extensive attention and preliminary applications in the fields of metals, ceramics, and intermetallic compounds. However, compared with alloys or ceramics, the preparation of high-entropy glasses is more difficult, and problems such as uneven heating are likely to occur during melting.

[0004] Therefore, it is necessary to develop new high-entropy oxide glasses and their preparation methods to improve the comprehensive performance of the glasses. Summary of the Invention

[0005] The present invention aims to solve one of the technical problems in the related art to a certain extent, and provides a preparation method and a kind of

[0006] As the first aspect of the present invention, a preparation method of a high-entropy oxide glass is provided, including:

[0007] Weigh metal oxide powders in a set ratio to obtain glass raw material powders, and the glass raw material powders include at least five metal oxides;

[0008] Perform multiple grinding and drying treatments on the glass raw material powders to obtain mixed powders;

[0009] After pressing and shaping the mixed powders, perform pre-sintering treatment to obtain initial wafers;

[0010] Crush the initial wafers to obtain a plurality of sample blocks, and the weight of a single sample block is between 30 mg and 150 mg;

[0011] Place the sample blocks in a suspension furnace, and a nozzle is provided at the bottom of the suspension furnace, and the nozzle is used to spray a set flow rate of gas into the suspension furnace so that the sample blocks are suspended in the suspension furnace;

[0012] Heat the sample block with multiple laser sources, and the multiple laser sources form multiple light spots on the surface of the sample block. There is a spacing between any adjacent light spots so that the sample block is completely melted to form a molten sphere. The heating temperature is between 1600 °C and 3300 °C, and the heating time is between 10 s and 60 s;

[0013] Rapidly cool the molten sphere at a cooling rate between 70 K / s and 300 K / s to prepare the high-entropy oxide glass.

[0014] Further, in the step of heating the sample block with multiple laser sources, the laser source includes a laser and a mirror. The laser forms a light spot on the surface of the sample block through the mirror, and the spacing between adjacent light spots is controlled by adjusting the angle of the mirror.

[0015] Further, the spacing between adjacent light spots is between 1.5 mm and 3 mm.

[0016] Further, in the step of heating the sample block with multiple laser sources, the angles of the mirrors are controlled so that multiple light spots are distributed on the edge surface of the sample block.

[0017] Further, the laser source includes a first laser source and multiple second laser sources. The first laser source forms a first light spot on the surface of the sample block, and the multiple second laser sources form multiple second light spots on the surface of the sample block. The multiple second light spots are distributed on the edge surface of the sample block. The first light spot is located on the surface of the central region of the sample block and between the multiple second light spots, and the temperature of the first light spot is higher than that of the second light spots.

[0018] Further, the temperatures of both the first light spot and the second light spots are between 2000 °C and 2500 °C.

[0019] Further, in the step of performing multiple grinding and drying treatments on the glass raw material powder, the drying temperature is between 40 °C and 60 °C, and the drying time is in the range of 1 hour to 3 hours;

[0020] In the step of performing pre-sintering treatment after compacting the mixed powder into a shape, the sintering temperature is between 900 °C and 1100 °C, and the sintering time is in the range of 1 hour to 3 hours.

[0021] Further, the metal oxides include at least five of lanthanum oxide, aluminum oxide, niobium oxide, titanium oxide, zirconium oxide, tantalum oxide, and hafnium oxide.

[0022] As a second aspect of the present application, a high-entropy oxide glass is disclosed, which is prepared by using the above preparation method.

[0023] Furthermore, the Young's modulus of the high-entropy oxide glass is between 140 GPa and 160 GPa, the hardness of the high-entropy oxide glass is between 9 GPa and 11 GPa, and the maximum transmittance of the high-entropy oxide glass in the visible light range of 400 nm to 800 nm is greater than 77%.

[0024] In the preparation method of the high-entropy oxide glass provided by this application, at least five metal oxides are used as the glass raw material powder, which can have a relatively high configurational entropy. By grinding and drying the glass raw material powder multiple times, the various oxides can be fully mixed and homogenized. After being pressed into a sheet and pre-sintered, the sample sheet can be made more dense, and defects such as internal impurities and gases can be removed. After sintering, the sample is further broken to select suitable blocks in terms of mass and shape, which can increase the suspension effect in the suspension furnace. More importantly, this application uses multiple laser sources to heat the blocks. The multiple laser sources can generate light spots at multiple positions on the surface of the blocks, so that the heating temperatures at multiple positions of the blocks are consistent, and a molten sphere can be obtained by uniform melting. Since the high-entropy oxide contains multiple metal oxides with different melting points, during the heating process, using a single heat source often results in high local heating temperature and uneven temperature. Compared with the traditional technology, the spacing of the multiple light spots can, on the one hand, maximize the heating effects in the heating center and the heating radiation area, and on the other hand, can simultaneously heat and melt metal oxides with different melting points, reduce crystallization, and accelerate the mixing of each component in the molten state into a liquid-liquid process, with a faster preparation speed. During the melting process, each component can be fully fused, avoiding local non-uniform distribution of elements in the high-entropy sample and crystallization and heterogeneous nucleation caused by long time.

[0025] The high-entropy oxide glass prepared by the preparation method of the high-entropy oxide glass of this application has uniform components, higher glass-forming ability, and a uniform amorphous morphology at each position. It not only has relatively high hardness and Young's modulus, but also has higher light transmittance and lower refractive index. When applied to the glass of electronic product displays, touch panels, and intelligent devices, it can effectively improve the anti-drop and wear resistance, and has a better display effect. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0027] Figure 1 It is a flowchart of an implementation manner of the preparation method of the high-entropy oxide glass provided by the present invention;

[0028] Figure 2 It is the cooling temperature change diagram in the preparation method of the high-entropy oxide glass provided by the present invention;

[0029] Figure 3 It is the X-ray diffraction spectrum of the high-entropy oxide glass of Example 1 of the present invention;

[0030] Figure 4 It is the X-ray diffraction spectrum of the high-entropy oxide glass of Comparative Example 8 of the present invention;

[0031] Figure 5 It is the test depth-hardness curve of the high-entropy oxide glass of Example 1 of the present invention;

[0032] Figure 6 It is the test depth-Young's modulus curve of the high-entropy oxide glass of Example 1 of the present invention;

[0033] Figure 7 It is a photograph of the high-entropy oxide glasses of Examples 1 to 3 of the present invention. Detailed Description of the Invention

[0034] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions throughout. Based on the embodiments in the embodiments, it is intended to explain the present invention and should not be construed as a limitation of the present invention.

[0035] As used herein, the phrase "in one embodiment" or "instance" or "example" means that a particular feature, structure, or characteristic described in connection with the embodiment itself may be included in at least one embodiment of the present disclosure. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

[0036] In recent years, high-entropy materials have received increasing attention and research as a brand-new material system. Such materials usually consist of five or more main components, and the cations of each component are in equimolar ratio of atoms. The emergence of high-entropy materials not only subverts the concept of single-component-based traditional material design, but also the increase in the number of main elements in the system provides a greater space for material composition design and structure-property optimization, and has received extensive attention and preliminary applications in the fields of metals, ceramics, and intermetallic compounds. The multi-main-component composition characteristics of high-entropy materials endow them with many unique effects, specifically including: the high-entropy effect in thermodynamics, the lattice distortion effect in structure, the sluggish diffusion effect in kinetics, and the cocktail effect in performance. Based on these effects, high-entropy materials show obvious advantages over traditional materials in terms of mechanical, physical, and chemical properties, and have become one of the important research hotspots in the domestic and foreign material fields. However, in related technologies, a large number of glass-forming oxides (such as SiO2, B2O3, P2O5, etc.) are still the main body. Although these low-dissociation-energy oxides have well improved the glass-forming ability, they have imposed certain limitations on the mechanical and optical properties of the glass.

[0037] Therefore, based on the concept of high entropy, the present invention develops a multi-component high-entropy oxide glass with high hardness and high Young's modulus, and provides its preparation method and application.

[0038] As the first aspect of the present invention, a preparation method of a high-entropy oxide glass is provided, as Figure 1 shown, including:

[0039] S100. Weigh metal oxide powders in a set ratio to obtain glass raw material powders, and the glass raw material powders include at least five metal oxides;

[0040] S110. Perform multiple grinding and drying treatments on the glass raw material powders to obtain mixed powders;

[0041] S120. After compacting and forming the mixed powders, perform pre-sintering treatment to obtain initial specimens;

[0042] S130. Crush the initial specimens to obtain a plurality of specimen blocks, and the weight of a single specimen block is between 30 mg and 150 mg;

[0043] S140. Place the specimen blocks in a suspension furnace, and a nozzle is provided at the bottom of the suspension furnace. The nozzle is used to inject a set flow rate of gas into the suspension furnace so that the specimen blocks are suspended in the suspension furnace;

[0044] S150. Heat the specimen blocks with multiple laser sources. The multiple laser sources form multiple light spots on the surface of the specimen blocks, and there is a spacing between any adjacent light spots, so that the specimen blocks are completely melted to form molten spheres. The heating temperature is between 1600 °C and 3300 °C, and the heating time is between 10 s and 60 s;

[0045] S160. Rapidly cool the molten sphere at a cooling rate between 70 K / s and 300 K / s to prepare a high-entropy oxide glass.

[0046] In the preparation method of the high-entropy oxide glass provided by this application, at least five metal oxides are used as glass raw material powders, which can have a relatively high configurational entropy. By grinding and drying the glass raw material powders multiple times, the various oxides can be fully mixed and homogenized. After being pressed into tablets and pre-sintered, the sample tablets can be made denser, and defects such as internal impurities and gases can be removed. After sintering, further crushing and selecting sample blocks with appropriate mass and shape can increase the suspension effect in the suspension furnace. More importantly, this application uses multiple laser sources to heat the sample blocks. The multiple laser sources can generate light spots at multiple positions on the surface of the sample blocks, so that the heating temperatures at multiple positions of the sample blocks are the same, and a molten sphere can be uniformly melted. Since the high-entropy oxide contains multiple metal oxides with different melting points, in the heating process, using a single heat source often results in high local heating temperature and uneven temperature. Compared with the traditional technology, the spacing of the multiple light spots set, on the one hand, can maximize the heating effects of the heating center and the heating radiation area, and on the other hand, can simultaneously heat and melt metal oxides with different melting points, reduce crystallization, and accelerate the mixing of each component in the molten state into a liquid-liquid process, with a faster preparation speed. During the melting process, each component can be fully fused, avoiding local non-uniform distribution of elements in the high-entropy sample and crystallization caused by long time.

[0047] In step S100, in order to obtain an oxide glass with excellent mechanical properties and apply it to electronic product display screens, precision instruments, touch panels, optical lenses, and intelligent devices, etc., the glass is required to have characteristics such as high hardness, high Young's modulus, and high transmittance.

[0048] This application does not make special limitations on the selection of metal oxides, as long as they meet the requirements of glass raw materials. In some embodiments, the selected metal oxides include at least five of lanthanum oxide, aluminum oxide, niobium oxide, titanium oxide, zirconium oxide, tantalum oxide, hafnium oxide, gadolinium oxide, and gallium oxide. This is based on Maxwell's electromagnetic theory and the classical theory of Lorentz light-medium interaction. The refractive index of the oxide glass increases with the increase in the oxygen ion packing density and ion polarizability. The above-mentioned oxides of La, Nb, and Ti have relatively small ionic radii and large ionic polarizabilities, which help to increase the refraction of the oxide glass.

[0049] Preferably, La2O3, Nb2O5, Ta2O5, and Al2O3 are selected as the first four, and at least one of TiO2, ZrO2, and HfO2 is selected. Among them, Al, Ti, and Zr all have relatively high dissociation energies, which contribute to improving the hardness and Young's modulus of the oxide glass. As glass raw materials, La, Nb, and Ta can provide sufficient hardness and Young's modulus on the one hand, and have relatively high visible light transmittance on the other hand, increasing the display effect. In addition, the selected TiO2, ZrO2, and HfO2 are all high-field-strength cation oxides, which help to increase the atomic packing density of the oxide glass and can also increase the coordination number of Al, further improving the glass hardness. Selecting the above components to be added to the oxide glass can further improve the mechanical properties of the oxide glass.

[0050] This application does not make special limitations on the proportion of metal oxides, as long as the high configurational entropy is satisfied. Generally, the content of high-entropy oxides between 5 mol% and 35 mol% has a relatively high configurational entropy. Preferably, the metal oxides in this application have an equiatomic and equimolar ratio. Under this ratio, the highest configurational entropy can be obtained. Utilizing the high-entropy effect, sluggish diffusion effect, and cocktail effect brought about by entropy increase can effectively improve the hardness and Young's modulus of the oxide glass. In addition, the equiatomic molar ratio enables the components in the high-entropy oxide glass to be replaced by other compounds with lower costs without significant performance degradation, which helps in the large-scale production of high-entropy oxide glass.

[0051] In step S110, the glass raw material powder is subjected to multiple grinding and drying treatments to obtain a mixed powder. Preferably, the drying temperature is between 40°C and 60°C, and the drying time is in the range of 1 hour to 3 hours. Specifically, after weighing the oxide raw material powder with a purity of 99.99% according to the set ratio, the weighed glass raw material powder is placed in a mortar, and sufficient ethanol is added for wet grinding. After the ethanol has fully volatilized, the glass raw material powder is placed in a blast drying oven and dried at 50°C for 2 hours. The fully dried glass raw material powder is added with ethanol for grinding again, and the above grinding-drying operation is repeated 2 times to ensure uniform mixing of the raw materials, obtaining a mixed powder.

[0052] In step S120, after the mixed powder is pressed into shape, a pre-sintering treatment is carried out to obtain an initial sample piece. Preferably, the sintering temperature is between 900°C and 1100°C, and the sintering time is in the range of 1 hour to 3 hours. Specifically, under a pressure of 30 MPa, the above mixed powder is pressed into a small round piece with a diameter of 20 mm and a thickness of about 3 mm. The round piece is placed in a muffle furnace and held at 1000°C for 2 hours to improve the strength of the round piece, obtaining an initial sample piece.

[0053] In step S130, the initial sample piece is broken to obtain a plurality of sample blocks, and the weight of a single sample block is between 30 mg and 150 mg to achieve a better suspension effect. During the breaking process, the sample blocks will break into various shapes and are no longer samples with a flat surface. Therefore, it is necessary to adjust the laser source spot to control the uniform heating of the irregular sample blocks by the spot.

[0054] In step S140, the sample blocks are placed in a suspension furnace. A nozzle is provided at the bottom of the suspension furnace, and the nozzle is used to inject a set flow rate of gas into the suspension furnace so that the sample blocks are suspended in the suspension furnace. In some embodiments, the gas includes at least one of oxygen, nitrogen, helium, argon, or air. Preferably, the gas is selected as oxygen. During the process of injecting towards the sample blocks, oxygen can avoid interacting with metal oxides at high temperatures, thereby reducing defects such as bubbles in the molten liquid. As an alternative implementation, the suspension furnace includes a cylindrical cavity with a platform and a sealing cover. The suspension nozzle is located at the center of the circular platform of the cavity. The size and shape of the nozzle can be designed and selected according to the preparation requirements of specific sample blocks. The nozzle is connected to a gas cylinder through a gas path, and the suspension preparation of the sample blocks is achieved by regulating the gas flow rate. During the experiment, to avoid the sample blocks falling into the gas path and causing blockage, generally, it is required that the selected inner diameter of the nozzle is smaller than the diameter of the sample blocks. At the same time, to ensure the stability of the sample blocks during suspension and prevent sticking to the wall, the inner diameter of the nozzle cannot be too small. Here, the selection standard for the inner diameter of the nozzle is generally greater than 10% of the diameter of the sample blocks and less than 50% of the diameter of the sample blocks.

[0055] In step S150, multiple laser sources are used to heat the sample blocks. Among them, the sample blocks include a first molten part and a second molten part. The laser sources form a plurality of spots on the surface of the first molten part so that the first molten part melts first and then exposes the second molten part. Under the suspension action of the gas nozzle, the second molten part turns up so that the laser sources can heat the second molten part. Finally, the sample blocks are completely melted to form molten spheres. Preferably, the heating temperature is between 1600 °C and 3300 °C, and the heating time is between 10 s and 60 s. Within this range, it can ensure that the selected metal oxides can be completely melted, creating a high-quality precursor for subsequent extremely cold acquisition of amorphous materials. However, the heating temperature should not be too high, as too high a heating temperature will result in a longer time to reach the required cooling temperature, and a longer time is prone to nucleation and crystallization, which is not conducive to the formation of glass.

[0056] In some embodiments, in the step of heating the sample blocks using multiple heating sources, the gas flow rate is increased so that after the first molten part melts and exposes the second molten part, the second molten part can be flipped and adjusted in position by the increased gas flow rate, allowing the laser sources to continue heating the surface of the second molten part.

[0057] In some embodiments, heating of the sample block is started. First, the position of the laser source on the surface of the sample block is set through the observation lens. When the laser source is in the off state, in order to determine the position of its light spot, a device similar to a laser pointer irradiation device is added, which can form a red dot on the surface of the sample block, so that the position of the light spot can be determined. After the position is determined, laser heating is started. The laser source forms a light spot on the upper surface of the sample block close to it. Since there is a shadow surface on the sample block that cannot be irradiated by the laser light spot, the melting time of the shadow surface is longer because it cannot be directly heated by the light spot. At this time, the sample block is divided into a pre-melt and a post-melt. That is, the pre-melt is first heated by the laser and melts and flows, then the post-melt is exposed. Under the action of the gas suspension at the bottom, the post-melt turns upward. Under the observation lens, the light spot irradiation surface (bright surface) suddenly changes to a dark surface (shadow surface), and then the light spot continues to heat the dark surface, and the dark surface becomes a bright surface. The bright and dark surface transformation occurs at a melting moment point under the lens. Starting from this moment and continuing to heat for 5 s to 30 s can ensure that the sample block is completely melted into a molten sphere, and then extremely rapid cooling is carried out. If the gas flow rate is not increased and the surface is not heated at multiple light spot intervals, the pre-melt surface cannot melt and flow quickly to expose the post-melt surface, and the melting state of the sample block at this time cannot be determined either. When the specific melting state of the sample block cannot be determined and extremely rapid cooling is carried out, on the one hand, it may cause insufficient heating time and incomplete melting, resulting in the inability to form glass; on the other hand, it may cause overheating and too long heating time, which makes the temperature difference too large during the subsequent extremely rapid cooling process, not only providing a large crystallization driving force, but also providing a longer cooling time for nucleation and crystallization, which is not conducive to the formation of amorphous.

[0058] This application does not make special limitations on how to control the light spot and its spacing of the laser source. As an optional implementation manner, the laser source includes a laser and a reflector. The laser forms a light spot on the surface of the sample block through the reflector, and the spacing between adjacent light spots is controlled by adjusting the angle of the reflector. Among them, the spacing between adjacent light spots is between 1.5 mm and 3 mm. The sample block can be efficiently melted within this spacing range. If the distance exceeds this range, the laser beam will not be able to heat the sample, reducing the melting efficiency; if the spacing is less than this range, it will cause too high a local melting temperature, resulting in uneven heating of the melt and problems such as local crystallization.

[0059] In some embodiments, since the sample is an irregularly shaped block formed by fragmentation and contains various metal oxides with large melting point differences inside, the heating is affected by the surface shape and composition of the block. This is very fatal for high-entropy oxide glasses because their composition and shape are uneven, and only a very small chemical driving force can cause local aggregation and segregation of the components, as well as problems of heterogeneous nucleation or crystallization due to uneven heating, resulting in a significant decline in the glass properties. Based on the above problems, this application will use multiple heating sources, and the light spots and their thermal influence areas are distributed at various positions on the surface of the block to eliminate the heating imbalance caused by the uneven composition and shape. In some embodiments, by controlling the angle of the reflector, multiple light spots are distributed on the edge surface of the block. Generally, the cooling rate at the edge of the block is fast and the temperature is lower than that at the center. If the light spots are arranged around the edge surface of the block, the edge will be preferentially heated, which can balance the temperature difference between the edge and the center and eliminate the crystallization driving force caused by temperature unevenness.

[0060] This application does not make special limitations on the light spot form of the laser source on the surface of the block. Preferably, the laser source includes a first laser source and multiple second laser sources. The first laser source forms a first light spot on the surface of the block, and multiple second laser sources form multiple second light spots on the surface of the block. The multiple second light spots are distributed on the edge surface of the block. The first light spot is located on the surface of the central region of the block and between the multiple second light spots. The temperature of the first light spot is higher than that of the second light spot. The first light spot is located at the central part of the molten block and serves to melt the block. The positions of the second light spots are the edge positions of the molten block, which serve to assist in melting and maintain better temperature uniformity. The multiple second light spots surround the first light spot to make the surface temperature of the block more uniform. Preferably, the temperature of the first light spot is higher than that of the second light spot.

[0061] In some specific embodiments, the first laser source is a solid laser source, the second laser source is a CO2 laser source, the heating power of the solid laser source is 100W, and the heating power of the CO2 laser source is 75W, so that the temperatures of the first light spot and the second light spot are both between 2000°C and 2500°C.

[0062] In step S160, as an alternative implementation, the cooling rate of this application is as Figure 2 shown. First, it is cooled to 1200 to 1500 degrees at a first speed, and then cooled to room temperature at a second speed. The first speed is greater than the second speed. The advantage of this cooling method is that rapid cooling in the high-temperature range can quickly solidify the high-temperature melt, greatly increasing the formation probability of amorphous high-entropy oxide glass; slower cooling in the low-temperature range can effectively release a part of the thermal stress existing inside the glass and prevent the glass ball from cracking.

[0063] The preparation method of the present application does not require ultra-fine powders with high uniformity and high sintering activity, avoiding the dependence on powders; it does not require long-time high-temperature and high-pressure sintering, has a simple process, and low energy consumption and equipment costs; each component can be fully fused during the melting process, avoiding local enrichment of high-entropy sample elements; during the solidification process, the nucleation and crystal growth time of high-entropy ceramic crystals are short, and it is easier to obtain ultra-fine crystals or even nano-high-entropy ceramics. The high-entropy melt completes the entire melting and solidification process under suspension, which can avoid contamination and heterogeneous nucleation caused by the container wall. In addition, the melt solidifies under high undercooling conditions, and it is expected to obtain crystal grains and microstructures with unique structures, thereby improving the properties of the material.

[0064] As the second aspect of the present application, a high-entropy oxide glass is disclosed, which is prepared by using the above-mentioned preparation method. The Young's modulus of the high-entropy oxide glass is between 140 GPa and 160 GPa, the hardness of the high-entropy oxide glass is between 9 GPa and 11 GPa, and the maximum transmittance of the high-entropy oxide glass in visible light of 400 nm - 800 nm is greater than 77%.

[0065] The high-entropy oxide glass prepared by the preparation method of the high-entropy oxide glass of the present application has uniform components, higher glass-forming ability, and uniform amorphous morphology at each position. It not only has high hardness and Young's modulus, but also has higher light transmittance and lower refractive index. When applied to electronic product display screens, touch panels and intelligent devices, it can effectively improve the drop resistance and wear resistance, and the display effect is better.

[0066] The present invention will be further elaborated below through specific examples and comparative examples.

[0067] Examples

[0068] Example 1

[0069] This example provides a high-hardness and high-Young's modulus high-entropy oxide glass and its preparation method. The preparation method includes:

[0070] Weigh at least five metal oxides in a set ratio as glass raw material powders. The metal oxides include the following components with a purity of 99.99%: La2O3, Nb2O5, Ta2O5, Al2O3, and TiO2. The atomic molar ratio is: La: 20%, Nb: 20%, Ta: 20%, Al: 20%, Ti: 20%;

[0071] The glass raw material powder is ground and dried multiple times to obtain a mixed powder. Specifically, the weighed glass raw material powder is placed in a mortar, and sufficient ethanol is added for wet grinding. After the ethanol has fully volatilized, the glass raw material powder is placed in a blast drying oven and dried at 50 °C for 2 hours. The fully dried glass raw material powder is added with ethanol for grinding again, and the above grinding-drying operation is repeated 2 times to ensure uniform mixing of the raw materials;

[0072] After the mixed powder is pressed into shape, it is subjected to pre-sintering treatment to obtain an initial sample piece. Specifically, the above mixed powder is pressed into a small round piece with a diameter of 20 mm and a thickness of about 3 mm under a pressure of 30 MPa, and the round piece is placed in a muffle furnace and kept at 1000 °C for 2 hours to improve the strength of the round piece;

[0073] The initial sample piece is broken to obtain multiple sample blocks, and the weight of a single sample block is between 30 mg and 150 mg;

[0074] The sample blocks are placed in a suspension furnace. There is a nozzle at the bottom of the floating furnace, and the gas ejected is oxygen to make the sample blocks float. Specifically, the suspension furnace includes a cylindrical cavity with a platform and a sealing cover. The suspension nozzle is located at the center of the circular platform of the cavity, and the nozzle is connected to an oxygen gas cylinder through a gas path. Sample blocks larger than 50% of the nozzle size are selected;

[0075] After the sample blocks are stably suspended in an oxygen atmosphere, multiple laser sources are used to heat the sample blocks. Specifically, first, the positions of the virtual light spots of the initial multiple laser sources are determined through an observation lens, and the positions of the virtual light spots are moved by adjusting the angle of the reflecting mirror so that the distance between adjacent light spots is between 1.5 mm and 3 mm. Among them, the laser sources are divided into a first laser source and multiple second laser sources. By controlling the angle of the reflecting mirror, the virtual second light spots formed by the multiple second laser sources are distributed on the edge surface of the sample block, and the virtual first light spot formed by the first laser source is located in the central area of the sample block and between the multiple second light spots. The power of the first laser source is greater than that of the second laser source;

[0076] Laser heating is started, and the heating temperature is set between 2000 °C and 3300 °C. After observing that the dark surface turns up under the observation lens, it is confirmed that the heating temperature is between 2000 °C and 3000 °C, and laser heating is maintained for 5 s to 30 s, and then the laser is turned off;

[0077] Subsequently, it is first cooled at a cooling rate of 260 K / s to between 1500 °C and 1000 °C, and then cooled to room temperature at a second cooling rate to obtain a high-entropy oxide glass as Specimen 1 (abbreviated as LNTAT). The corresponding XRD pattern is as Figure 3 shown Figure 3 No crystal peak pattern appears, which is a typical amorphous peak. Thus, it can be proved that the glass prepared in this application is in a completely amorphous form.

[0078] Example 2

[0079] Sample 2 (abbreviated as LNTAZ) was prepared by the same preparation method as in the example. The difference is that TiO2 in Example 1 was replaced with ZrO2, and the atomic molar ratio is: La: 20%, Nb: 20%, Ta: 20%, Al: 20%, Zr: 20%.

[0080] Example 3

[0081] Sample 3 (abbreviated as LNTAH) was prepared by the same preparation method as in Example 1. The difference is that TiO2 in Example 1 was replaced with HfO2, and the atomic molar ratio is: La: 20%, Nb: 20%, Ta: 20%, Al: 20%, Hf: 20%.

[0082] Example 4

[0083] Sample 4 (abbreviated as LNZAT) was prepared by the same preparation method as in Example 1. The difference is that Ta2O5 in Example 1 was replaced with ZrO2, and the atomic molar ratio is: La: 20%, Nb: 20%, Zr: 20%, Al: 20%, Ti: 20%.

[0084] Example 5

[0085] Sample 5 (abbreviated as LNTTZ) was prepared by the same preparation method as in Example 1. The difference is that Al2O3 in Example 1 was replaced with ZrO2, and the atomic molar ratio is: La: 20%, Nb: 20%, Ta: 20%, Zr: 20%, Ti: 20%.

[0086] Example 6

[0087] Sample 6 (abbreviated as LNGAT) was prepared by the same preparation method as in Example 1. The difference is that ZrO2 in Example 1 was replaced with Gd2O3, and the atomic molar ratio is: La: 20%, Nb: 20%, Ti: 20%, Al: 20%, Gd: 20%.

[0088] Comparative Example 1

[0089] Sample 7 was prepared by the same preparation method as in Example 1. The difference is that the set ratio of the weighed oxides is: La2O3 17 mol%, Nb2O5 16 mol%, TiO2 33 mol%, Al2O3 17 mol%, Ta2O5 17 mol.

[0090] Comparative Example 2

[0091] Sample 8 was prepared using the same preparation method as in Example 1, except that the set ratios of the weighed oxides were: La2O3 19 mol%, Nb2O5 16 mol%, TiO2 33 mol%, Al2O3 15 mol%, Ta2O5 17 mol.

[0092] Comparative Example 3

[0093] Sample 9 was prepared using the same preparation method as in Example 1, except that the set ratios of the weighed oxides were: La2O3 21 mol%, Nb2O5 16 mol%, TiO2 33 mol%, Al2O3 13 mol%, Ta2O5 17 mol.

[0094] Comparative Example 4

[0095] Sample 10 was prepared using the same preparation method as in Example 2, except that the set ratios of the weighed oxides were: La2O3 25 mol%, Nb2O5 20 mol%, TiO2 30 mol%, Al2O3 15 mol%, ZrO2 10 mol.

[0096] Comparative Example 5

[0097] Sample 11 was prepared using the same preparation method as in Example 2, except that the set ratios of the weighed oxides were: La2O3 25 mol%, Nb2O5 20 mol%, TiO2 27 mol%, Al2O3 15 mol%, ZrO2 13 mol.

[0098] Comparative Example 6

[0099] Sample 12 was prepared using the same preparation method as in Example 2, except that the set ratios of the weighed oxides were: La2O3 25 mol%, Nb2O5 20 mol%, TiO2 24 mol%, Al2O3 15 mol%, ZrO2 16 mol.

[0100] Comparative Example 7

[0101] Sample 13 was prepared using the same preparation method as in Example 1, except that TiO2 in Example 1 was replaced with Fe2O3, and Sample 13 was obtained according to the atomic molar ratio: La: 20%, Nb: 20%, Ta: 20%, Al: 20%, Fe: 20%.

[0102] Comparative Example 8

[0103] Specimen 14 was prepared using the same preparation method as in Example 1, except that the position of the virtual light spot was moved by adjusting the mirror angle so that the distance between adjacent light spots was 1 mm.

[0104] Comparative Example 9

[0105] Specimen 15 was prepared using the same preparation method as in Example 1, except that the position of the virtual light spot was moved by adjusting the mirror angle so that the distance between adjacent light spots was 4 mm.

[0106] Test Example

[0107] Using an X-ray diffractometer, phase analysis was performed on the high-entropy oxide glasses obtained in Example 1 and Comparative Example 8. The results are as Figure 3 and Figure 4 shown. Figure 3 No crystal peak pattern appeared, which was a typical amorphous peak. Thus, it can be proved that the glass prepared with the light spot spacing of this application is in a completely amorphous state, while Figure 4 crystallization characteristic peaks appeared, indicating that if the light spot spacing is too small, the irregular sample surface may not be uniformly heated, resulting in local nucleation and crystallization.

[0108] The high-entropy oxide glasses prepared in the above examples and comparative examples were subjected to the following performance tests: (1) Hardness and Young's modulus were both measured by a nanoindenter; (2) The maximum transmittance in the visible light range of 400 nm to 800 nm was measured by an ultraviolet-visible spectrophotometer.

[0109] The specific performance test results were summarized in Table 1, and the hardness and Young's modulus results corresponding to the high-entropy oxide glass of Example 1 were plotted separately in Figure 5 and Figure 6 respectively. The optical photos of Examples 1 to 3 are as Figure 7 shown, and it can be seen that the glasses of the examples all have good transmittance.

[0110] Table 1

[0111]

[0112] As can be seen from Table 1, when comparing Example 1 with Comparative Example 9, when the light spot spacing exceeds 3 mm, for example, when it is 4 mm, the uneven heating degree of the irregular sample by the laser source is aggravated. The hardness and Young's modulus of the prepared Specimen 9 are significantly reduced, and the transmittance also decreases. In severe cases, the laser beam cannot heat the sample, reducing the melting efficiency.

[0113] As can be seen from Examples 1 to 6, in the case of adopting an equiatomic molar ratio in this application, within the specific high-entropy oxide selection range of this application, it can be arbitrarily replaced without significant performance degradation. This is also because the equiatomic ratio has the highest configurational entropy. Under the conditions of meeting the material dissociation energy and high-field strength performance, arbitrary replacement will not affect the high-entropy effect. Comparing Comparative Example 1 to Comparative Example 6, in the case of non-equiatomic ratios, the configurational entropy is lower, and the system architecture is unstable. Arbitrarily replacing metal oxides will cause a significant decrease in product performance, and the unstable entropy value leads to a greater change in the high-entropy effect.

[0114] Comparing Example 1 with Comparative Example 7, the type of other oxides plays a key role in whether oxide glass can be prepared. Since Comparative Example 1 uses Fe2O3 as the metal oxide, the solid prepared is not oxide glass, and its light transmittance performance is poor. The hardness and Young's modulus were not characterized.

[0115] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing high entropy oxide glass, characterized in that: include: Weighing a set ratio of metal oxide powders to obtain glass raw material powder, wherein the glass raw material powder includes at least five metal oxides; Grinding and drying the glass raw material powder multiple times to obtain a mixed powder; The mixed powder is pressed into shape and then pre-sintered to obtain an initial sample; Crushing the initial sample to obtain a plurality of sample blocks, wherein the weight of each sample block is between 30 mg and 150 mg; Placing the sample block in a suspension furnace, wherein a nozzle is provided at the bottom of the suspension furnace, and the nozzle is used to spray a set flow of gas into the suspension furnace so that the sample block is suspended in the suspension furnace; The sample block is heated by using multiple laser sources, wherein the multiple laser sources form multiple light spots on the surface of the sample block, and there is a spacing between any adjacent light spots, so that the sample block is completely melted to form a molten sphere, the heating temperature is between 1600° C. and 3300° C., and the heating time is between 10s and 60s; The molten sphere is rapidly cooled at a cooling rate between 70K / s and 300K / s to prepare the high entropy oxide glass.

2. The preparation method according to claim 1, characterized in that: In the step of heating the sample block with multiple laser sources, the laser source includes a laser and a reflector, the laser forms a light spot on the surface of the sample block through the reflector, and the spacing between adjacent light spots is controlled by adjusting the angle of the reflector.

3. The preparation method according to claim 2, characterized in that: The interval between adjacent light spots is between 1.5 mm and 3 mm.

4. The preparation method according to claim 2, characterized in that: In the step of heating the sample block by using a plurality of laser sources, the angle of the reflector is controlled so that the plurality of light spots are distributed on the edge surface of the sample block.

5. The preparation method according to claim 1, characterized in that: The laser source includes a first laser source and a plurality of second laser sources, the first laser source forms a first light spot on the surface of the sample block, the plurality of second laser sources form a plurality of second light spots on the surface of the sample block, the plurality of second light spots are distributed on the edge surface of the sample block, the first light spot is located on the surface of the central area of ​​the sample block and between the plurality of second light spots, and the temperature of the first light spot is higher than that of the second light spot.

6. The preparation method according to claim 5, characterized in that: The temperatures of the first light spot and the second light spot are both between 2000° C. and 2500° C.

7. The preparation method according to any one of claims 1 to 6, characterized in that: In the step of grinding and drying the glass raw material powder for multiple times, the drying temperature is between 40° C. and 60° C., and the drying time is within the range of 1 hour to 3 hours; In the step of pre-sintering the mixed powder after compacting, the sintering temperature is between 900° C. and 1100° C., and the sintering time is within the range of 1 hour to 3 hours.

8. The preparation method according to any one of claims 1 to 6, characterized in that: The metal oxides include at least five of lanthanum oxide, aluminum oxide, niobium oxide, titanium oxide, zirconium oxide, tantalum oxide, and hafnium oxide.

9. A high entropy oxide glass, characterized in that: The preparation method is described in any one of claims 1 to 8.

10. The preparation method according to claim 9, characterized in that: The Young's modulus of the high entropy oxide glass is between 140 GPa and 160 GPa, the hardness of the high entropy oxide glass is between 9 GPa and 11 GPa, and the maximum transmittance of the high entropy oxide glass in the visible light range of 400 nm to 800 nm is greater than 77%.

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