An infrared transparent ceramic material having a wide transmission wavelength band and a method of manufacturing the same

Abstract

This invention discloses an infrared transparent ceramic material with a wide transmission band and its preparation method, belonging to the field of inorganic ceramic materials. The chemical formula of the infrared transparent ceramic material is (Y0...). 1‑x Re x )2O3-(Mg 1‑y Re y )O,0< x <4%; 0< y <30%; Re=Zn 2+ Mn 2+ Ni 2+ One of them; the preparation method of infrared transparent ceramic material includes the following steps: first, prepare primary Y2O3-(Mg 1‑y Re y O powder; place the powder and binder in a ball mill jar, and add molar percentage of x Re 2+ A solution of the compound was ball-milled to obtain a slurry; the slurry was dried, pulverized, sieved, and calcined to obtain (Y). 1‑x Re x )2O3-(Mg 1‑y Re y Y₂O₃ nanopowder was subjected to equiaxed biaxial pressing and molding, followed by the addition of (Y₂O₃) nanopowder. 1‑x Re x )2O3-(Mg 1‑y Re y O2 powder is formed, and then Y2O3 nanoparticles are added and formed to obtain a ceramic green body with a composite structure. The ceramic green body is then subjected to double-sided laser sintering, and the Y2O3 on the top and bottom surfaces is removed, followed by double-sided polishing to obtain the infrared transparent ceramic material. This invention employs a green body composite structure design and laser sintering technology, which effectively avoids oxygen vacancy defects generated by traditional sintering, thus eliminating the need for air annealing and effectively avoiding Re... 2+ The challenges of unstable valence states and easy oxidation are addressed by laser sintering. Laser sintering achieves densification of multiphase ceramics in a very short time, while effectively suppressing grain size, avoiding grain scattering, and improving the near-infrared transmittance of ceramics.

Description

Technical Field

[0001] This invention belongs to the field of inorganic ceramic materials, specifically relating to an infrared transparent ceramic material with a wide transmission band and its preparation method. Background Technology

[0002] Infrared window materials are crucial components of infrared imaging systems, serving to transmit target signals, maintain aerodynamic shape, and protect internal components. This necessitates that infrared window materials possess high optical transmittance in the operating wavelength range, as well as high strength and hardness in their mechanical properties. Ceramics often exhibit higher thermal conductivity and strength, and their fabrication cycle is short, production cost is low, and it is easier to fabricate large-size devices according to the required shape. Among them, Y2O3–MgO multiphase ceramics, with their high transmittance, excellent mechanical properties, good thermal properties, extremely low thermal emissivity, and thermal shock resistance second only to sapphire, are considered the most promising infrared window materials for high Mach applications. However, Y2O3-MgO multiphase ceramics currently face two main bottleneck problems: 1. Due to the unavoidable optical scattering caused by the refractive index difference between the two phases, Y₂O₃-MgO composite ceramics are only transparent in the mid-infrared band. Transmittance decreases from 3 μm to shorter wavelengths, and they become completely opaque even in wavelengths less than 1.5 μm, making it difficult to meet the requirements of future laser-infrared multi-band composite guidance. Existing techniques have shown that introducing dopants such as ZnO, NiO, MnO, or CaO into MgO can minimize the refractive index difference. However, the transition metal ion Ni... 2+ / Ni 3+ Mn 2+ / Mn 3+ / Mn 4+ In the ceramic manufacturing process, valence state changes are easily caused by the sintering atmosphere and vacancy defects. Furthermore, it is difficult to simultaneously eliminate vacancy defects and reduce transition metal ions during the subsequent annealing process.

[0003] 2. The grain size of Y₂O₃-MgO infrared transparent multiphase ceramics plays a crucial role in their near-infrared transmittance. Therefore, inhibiting grain growth in Y₂O₃-MgO infrared transparent multiphase ceramics is an effective means to achieve high strength and high infrared transmittance in ceramics. Related studies have shown that ( Journal of the European Ceramic Society 42 (2022) 2478–2486 Introducing divalent dopants into single-phase Y₂O₃ can promote the densification of Y₂O₃ ceramics. However, in the preparation of Y₂O₃-MgO multiphase ceramic samples, it is usually difficult to achieve grain size suppression and sintering densification, resulting in severe scattering from grain boundaries and micropores. This is detrimental to improving the mechanical and optical properties of the ceramics, which further limits the application of Y₂O₃-MgO multiphase ceramics in hypersonic vehicles and infrared guidance fields.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide an infrared transparent ceramic material with a wide transmission band and its preparation method, aiming to solve the problems that the existing doped transition metal ions are easily affected by the sintering atmosphere and vacancy defects in the preparation process of infrared transparent ceramic materials, which easily cause valence state changes, and it is difficult to simultaneously eliminate vacancy defects and reduce transition metal ions in the subsequent annealing process; as well as the problems that the existing preparation methods are difficult to achieve grain size suppression and sintering densification.

[0006] The technical solution adopted in this invention is as follows: In a first aspect, the present invention provides a method for preparing an infrared transparent ceramic material having a wide transmission band, wherein the chemical formula of the infrared transparent ceramic material is (Y 1-x Re x )2O3-(Mg 1-y Re y )O, where 0 < x <4%; 0< y <30%; Re=Zn 2+ Mn 2+ Ni 2+ One of them; The preparation method of the infrared transparent ceramic material includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 1-y Re y )O weighing Y 3+ compounds, Mg 2+ The compounds and their molar percentages are y Re 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare a raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix the transparent solution with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it at 180~240°C for 3~6 h to obtain precursor powder; Step 4: Place the precursor powder obtained in Step 3 in a muffle furnace and calcine it at 900~1100°C for 5~10 h to obtain primary Y2O3-(Mg 1-y Re y )O powder; Step 5, the primary Y2O3-(Mg) obtained in step 4 1-y Rey The O powder and binder were placed in a ball mill jar, and the molar percentage of the added powder was 1. x Re 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added. The mixture was then subjected to planetary ball milling at a ball milling speed of 120-180 r / min for 12-24 h to obtain a slurry, in which the primary Y2O3-(Mg) 1-y Re y The mass ratio of O powder to anhydrous ethanol is 1:1 to 1:2. Step 6: Dry the slurry obtained after ball milling in Step 5 at 40-60 °C for 10-24 h. Then, pulverize the dried slurry, pass it through a 100-200 mesh sieve, and then calcine it in a muffle furnace at 500-800 °C for 2-5 h to obtain (Y). 1-x Re x )2O3-(Mg 1-y Re y O powder; Step 7: Place yttrium oxide powder, sintering aid (such as ZrO2, La2O3) and solvent (such as anhydrous ethanol) in a ball milling device containing ball milling media (such as ZrO2) for ball milling. Dry and sieve the ball-milled slurry in sequence to obtain Y2O3 nano powder. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank (the blank is circular) has a diameter of 8~20 mm, the molding pressure is 10~20 MPa, and the holding pressure is 5~10 s. Then, (Y) is added. 1-x Re x )2O3-(Mg 1-y Re y Y₂O₃ nanoparticles are first added, and the molding pressure is 10-20 MPa, with a holding time of 5-10 s. Then, Y₂O₃ nanoparticles are added, and the molding pressure is 500-1200 MPa, with a holding time of 200-400 s, to obtain a ceramic green body with a composite structure. The ceramic green body with the composite structure includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 1- x Re x )2O3-(Mg 1-y Re y O; Step 9: Place the ceramic green body on a Y2O3 pad and perform double-sided laser sintering on the ceramic green body using a laser without annealing to obtain a composite structure ceramic. See [link to relevant documentation]. Figure 1 As shown; The upper and lower surface layers of the composite ceramic structure are removed, and double-sided polishing is performed to obtain the infrared transparent ceramic material.

[0007] Existing techniques have shown that introducing dopants such as ZnO, NiO, MnO, or CaO into MgO alone can minimize the refractive index difference. However, transition metal ions such as NiO... 2+ / Ni 3+ Mn 2+ / Mn 3+ / Mn 4+ In ceramic fabrication processes, valence state changes are easily induced by the sintering atmosphere and vacancy defects. Furthermore, it is difficult to simultaneously eliminate vacancy defects and reduce transition metal ions during subsequent annealing. In addition, existing techniques for preparing Y₂O₃-MgO multiphase ceramic samples typically struggle to suppress grain size and achieve sintering densification, resulting in severe grain boundary and micropore scattering, which is detrimental to improving the mechanical and optical properties of the ceramics.

[0008] Compared with existing sintering methods, this invention uses laser sintering technology, which can effectively avoid oxygen vacancy defects generated during traditional hot pressing and hot isostatic pressing of multiphase ceramics. Therefore, it eliminates the need for air annealing and effectively avoids Re 2+ The challenges of unstable valence states and easy oxidation are addressed by maintaining the valence state balance among the ions in the compound. Furthermore, laser sintering can achieve ceramic densification in a very short time, while effectively suppressing grain size, avoiding grain scattering problems caused by excessively large grains, and improving the near-infrared transmittance of the ceramic.

[0009] Furthermore, in preparing the infrared transparent ceramic material, this invention first creates a composite structure with upper and lower surface layers, then performs laser sintering on this composite structure, and finally removes the upper and lower surface layers to obtain the infrared transparent ceramic material. This is because, during the laser sintering process, the Y2O3 ceramic layers serving as the upper and lower surface layers can further isolate oxygen vacancies, preventing abnormal growth of core grains and changes in the valence state of doped transition metal ions; it can also act as a "bonding layer," preventing cracking of the internal core ceramic layer due to inconsistent thermal expansion coefficients.

[0010] Furthermore, the infrared transparent ceramic material with a wide transmission band provided by this invention will enhance Re 2+ Simultaneously introduced into the Y2O3 and MgO phases, the densification temperature of the nano-multiphase infrared transparent ceramic material is reduced, the grain size is decreased, and the refractive index difference between the two phases is reduced, thereby effectively improving the near-infrared transmittance of the infrared transparent ceramic material.

[0011] The method for preparing infrared transparent ceramic materials with a wide transmission band provided by this invention improves the stability of the materials.

[0012] Furthermore, in step 4, the calcination temperature is 900~1100°C (e.g., 900°C, 1000°C, 1100°C, etc.), and the calcination time is 5~10 h (e.g., 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, etc.). Calcination under these conditions ensures that the molar percentage is [value missing]. y Re 2+ It enters the MgO lattice to form a stable compound.

[0013] Furthermore, in step 4, the mass-volume loading coefficient corresponding to the precursor powder mass and the muffle furnace volume is 1.5~8.0 kg / m³. 3 For example, 1.5 kg / m 3 2.5 kg / m 3 3.0 kg / m 3 3.5 kg / m 3 4.5 kg / m 3 5.0 kg / m 3 6.0kg / m 3 7.0 kg / m 3 8.0 kg / m 3 Other specific point values ​​within the above range can be selected, and will not be listed here one by one. By adopting this loading coefficient, under the premise of fully excluding organic substances such as citric acid and ethylene glycol, particle growth and sintering necks can be further avoided, thereby ensuring the sintering activity of the powder.

[0014] Further, in step 5, the binder is oleic acid polyoxyethylene ester, and the amount added is primary Y2O3-(Mg 1-y Re y The binder, at 0.4% to 1.2% of the powder mass, generates a bubble-free lubricating layer during tableting, promoting the flow of the granules under pressure, ensuring uniform pressure distribution, reducing internal structural stress in the green blank, and preventing damage such as cracking and spalling during laser sintering.

[0015] Furthermore, in step 6, the calcination temperature is 500~800 °C (e.g., 500 °C, 600 °C, 700 °C, 800 °C, etc.), and the calcination time is 2~5 h (e.g., 2 h, 3 h, 4 h, 5 h, etc.). Calcination under these conditions can ensure that the molar percentage is [value missing]. x Re 2+ It enters the Y2O3 lattice.

[0016] Furthermore, in step 9, during the laser sintering process, the laser is a CO2 laser with a laser source wavelength of 10.6μm (the transmittance of the ceramic blank in this wavelength band is 0, which can fully absorb heat and achieve rapid heating), and the spot diameter is 5~16mm (slightly larger than the diameter of the ceramic blank, so that the sample can be heated uniformly).

[0017] Laser sintering comprises two stages: a preheating stage and a heating stage. The preheating irradiation time for the ceramic green body is 80–150 s, and the laser power is 80–100 W. The preheating stage removes organic matter from the ceramic green body. Furthermore, to ensure the ceramic green body retains a certain initial mechanical strength after the simplified cold isostatic pressing process, preheating is necessary to give it a certain initial mechanical strength. Additionally, the specific heat capacity of the surface Y₂O₃ layer (0.44 J / g·K) is lower than that of the core layer (Y₂O₃). 1-x Re x )2O3-(Mg 1- y Re y Given the specific heat capacity of O (0.66 J / g·K), it is necessary to rationally design the preheating irradiation time in (Y) 1-x Re x )2O3-(Mg 1-y Re y ) Store enough heat energy in the O phase, while avoiding (Y) 1-x Re x )2O3-(Mg 1-y Re y The O phase grains grow, thus avoiding differential sintering caused by different specific heat capacities during subsequent heating.

[0018] The irradiation time for heating the ceramic green body is 200~300 s, and the laser power is 250~350 W. The irradiation time and power directly affect the grain growth during the densification process of multiphase ceramics. It is necessary to quickly achieve the densification of ceramic materials under appropriate power in a short time to avoid grain growth, thereby ensuring high optical transmittance and strength.

[0019] After the laser sintering is completed, the cooling stage begins. Specifically, the laser irradiation time is controlled at 100-150 seconds, and the laser power is reduced to 0-100 W to avoid the product cracking and deformation due to excessively rapid cooling.

[0020] Furthermore, x=0.008, y=0.25, Re=Mn 2+ At this value and with the doped ions, infrared transparent ceramic materials exhibit a small near-infrared cutoff wavelength and high flexural strength.

[0021] Furthermore, the core layer has a thickness of 1-4 mm, the surface layer has a thickness of 0.5-2 mm, and the thickness ratio of the upper surface layer, core layer, and lower surface layer is 1:3:1 to 1:2:1.

[0022] Furthermore, the near-infrared cutoff wavelength (the incident light wavelength corresponding to a transmittance of 10% for infrared transparent ceramic materials with a wide transmission band) is 835~984 nm.

[0023] In a second aspect, the present invention provides an infrared transparent ceramic material having a wide transmission band, wherein the infrared transparent ceramic material is prepared by the preparation method described in the present invention.

[0024] The chemical formula of the infrared transparent ceramic material described in this invention is (Y 1-x Re x )2O3-(Mg 1-y Re y )O, where 0 < x <4%; 0< y <30%; Re=Zn 2+ Mn 2+ Ni 2+ One of them. Preferably, x=0.008, y=0.25.

[0025] The infrared transparent ceramic material of the present invention has a wide transmission spectrum, small grain size (117~147 nm), and high characteristic bending strength (415~435 MPa). Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the composite ceramic structure with upper and lower surface layers first prepared during the preparation of infrared transparent ceramic materials according to the present invention. Figure 2 The X-ray diffraction pattern of the infrared transparent ceramic material with a wide transmission band prepared in Example 1 of the present invention is shown. The horizontal axis represents the incident angle of the X-rays, and the vertical axis represents the diffraction intensity. Figure 3 The visible-near-infrared transmittance curve of the infrared transparent ceramic material with a wide transmission band prepared in Example 1 of the present invention is shown. The horizontal axis represents wavelength and the vertical axis represents linear transmittance. Figure 4 SEM image of the cross section of the infrared transparent ceramic material with a wide transmission band prepared in Example 1 of the present invention and the corresponding statistical distribution of grain size; Figure 5 The Weibull distribution curve of the flexural strength of the infrared transparent ceramic material with a wide transmission band prepared in Example 1 of the present invention is shown. The horizontal axis represents the flexural strength and the vertical axis represents the fracture probability. Figure 6 The transmittance curve of the infrared transparent ceramic material with a wide transmission band prepared in Example 2 of the present invention is shown. The horizontal axis represents wavelength and the vertical axis represents linear transmittance. Figure 7 The X-ray photoelectron spectrum of Mn ions in the infrared transparent ceramic material with a wide transmission band prepared in Example 3 of the present invention is shown. The horizontal axis represents the binding energy and the vertical axis represents the corresponding intensity. Figure 8 The electron paramagnetic resonance spectrum of the infrared transparent ceramic material with a wide transmission band prepared in Example 3 of the present invention is shown. The horizontal axis represents the magnetic field strength and the vertical axis represents the resonance intensity. Figure 9 The visible-near-infrared transmittance curve of the infrared transparent ceramic material with a wide transmittance band prepared in Example 3 of the present invention is shown. The horizontal axis represents wavelength and the vertical axis represents linear transmittance. Figure 10 The cell parameter variation diagrams are shown for the infrared transparent ceramic materials with a wide transmission band prepared in Examples 3 and 4 of this invention. Figure 11 The image shows the SEM image of the infrared transparent ceramic material with a wide transmission band prepared in Comparative Example 2 of this invention. Figure 12 The visible-near-infrared transmittance curve of the infrared transparent ceramic material with a wide transmittance band prepared in Example 5 of the present invention is shown. The horizontal axis represents wavelength and the vertical axis represents linear transmittance. Detailed Implementation

[0027] This invention provides an infrared transparent ceramic material with a wide transmission band and its preparation method. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0028] To prepare 100 g of the target product, the raw material powders were weighed separately, and the ingredient list is shown in Table 1. The measurement methods used in the following examples are all conventional techniques in the art, and the materials are all commercially available finished products, which will not be described in detail here.

[0029] Table 1 Ingredients list for the embodiment

[0030] Example 1 An infrared transparent ceramic material with a wide transmission band, its chemical formula is (Y 0.98 Zn 0.02 )2O3-(Mg 0.8 Zn 0.2 O; The preparation method of the above-mentioned infrared transparent ceramic material includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 0.8 Zn 0.2 )O weighing Y 3+ Compounds, Mg 2+ The compound and Zn with a molar percentage of 20% 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare the corresponding raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix it with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it to obtain precursor powder. The calcination temperature is 180°C and the calcination time is 3 h. Step 4: The precursor powder obtained in Step 3 is calcined in a muffle furnace to obtain primary Y2O3-(Mg) 0.8 Zn 0.2 O powder, calcined at 900°C for 5 h, with a precursor powder mass-to-muffle furnace volume loading coefficient of 1.5 kg / m³. 3 ; Step 5: Place the powder and binder (i.e., oleic acid polyoxyethylene ester) obtained in Step 4 into a ball mill jar, and add 2% (molar percentage) of Zn. 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added for planetary ball milling. The mass ratio of powder to anhydrous ethanol was 1:1, the ball milling speed was 120 r / min, and the ball milling time was 12 h. Step 6: The slurry obtained after ball milling in Step 5 is dried at 40 °C for 10 h. The dried slurry is then pulverized, passed through a 100-mesh sieve, and subsequently calcined in a muffle furnace at 500 °C for 2 h to obtain (Y). 0.98 Zn 0.02 )2O3-(Mg 0.8 Zn 0.2 O powder; Step 7: Yttrium oxide powder, sintering aid (ZrO2) and solvent (anhydrous ethanol) are placed in a ball milling device containing ball milling media (ZrO2) for ball milling to obtain a ball-milled slurry; the ball-milled slurry is then dried and passed through a 200-mesh sieve to obtain Y2O3 nanoparticles. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank diameter is 8 mm, the molding pressure is 10 MPa, and the holding pressure is 7 s. Then, (Y) is added. 0.98 Zn0.02 )2O3-(Mg 0.8 Zn 0.2 Y₂O₃ nanoparticles are first added, and the molding pressure is 10 MPa for 7 seconds. Then, Y₂O₃ nanoparticles are added, and the molding pressure is increased to 500 MPa for 200 seconds to obtain a ceramic green body with a composite structure. This ceramic green body includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 0.98 Zn 0.02 )2O3-(Mg 0.8 Zn 0.2 O; Step 9: Place the ceramic green body on a Y2O3 pad and perform double-sided laser sintering on the ceramic green body using a laser to obtain a composite structure ceramic. The laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 5 mm. The preheating irradiation time of the ceramic green body is 80 s, and the laser power is increased to 80 W; the heating irradiation time of the ceramic green body is 200 s, and the laser power is increased to 250 W; the cooling irradiation time is 100 s, and the laser power is reduced to 0. No annealing is required. The upper and lower surface layers of the composite structure ceramic are removed by grinding, and double-sided polishing is performed to obtain (Y2O3) composite structure ceramic. 0.98 Zn 0.02 )2O3-(Mg 0.8 Zn 0.2 Infrared transparent ceramic material.

[0031] Figure 2 The X-ray diffraction (XRD) pattern of the infrared transparent ceramic material prepared in this embodiment shows that the X-ray diffraction peaks of the prepared infrared transparent ceramic material are consistent with the standard cards of cubic Y2O3 (PDF 41-1105) and cubic MgO (PDF45-0946).

[0032] Figure 3 The infrared transmittance curve of the infrared transparent ceramic material prepared in this embodiment shows that its near-infrared cutoff wavelength is 984 nm.

[0033] Figure 4 The images shown are scanning electron microscope images of the infrared transparent ceramic material prepared in this embodiment and the corresponding statistical distribution of grain size. The results show that the average grain size is 130 nm.

[0034] Figure 5The Weibull distribution diagram of the flexural strength of the infrared transparent ceramic material prepared in this embodiment shows that its characteristic flexural strength (the flexural strength value corresponding to a fracture probability of 62.2% when the measured flexural strength values ​​are analyzed according to the Weibull distribution probability) is 415 MPa.

[0035] Example 2 An infrared transparent ceramic material with a wide transmission band, its chemical formula is (Y 0.97 Zn 0.03 )2O3-(Mg 0.75 Zn 0.25 O; The preparation method of the above-mentioned infrared transparent ceramic material includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 0.75 Zn 0.25 )O weighing Y 3+ Compounds, Mg 2+ The compound and Zn with a molar percentage of 25% 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare the corresponding raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix it with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it to obtain precursor powder. The calcination temperature is 200°C and the calcination time is 4.5 h. Step 4: The precursor powder obtained in Step 3 is calcined in a muffle furnace to obtain primary Y2O3-(Mg) 0.75 Zn 0.25 O powder, calcined at 950°C for 6.5 h, with a precursor powder mass-to-muffle furnace volume loading coefficient of 4 kg / m³. 3 ; Step 5: Place the powder and binder (i.e., oleic acid polyoxyethylene ester) obtained in Step 4 into a ball mill jar, and add 3% (molar percentage) of Zn. 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added for planetary ball milling. The mass ratio of powder to anhydrous ethanol was 1:1.5, the ball milling speed was 150 r / min, and the ball milling time was 18 h. Step 6: The slurry obtained after ball milling in Step 5 is dried at 50 °C for 18 h. The dried slurry is then pulverized, passed through a 200-mesh sieve, and subsequently calcined in a muffle furnace at 700 °C for 3 h to obtain (Y). 0.97 Zn0.03 )2O3-(Mg 0.75 Zn 0.25 O powder; Step 7: Yttrium oxide powder, sintering aid (ZrO2) and solvent (ZrO2) are placed in a ball milling device containing ball milling media (ZrO2) for ball milling to obtain a ball-milled slurry; the ball-milled slurry is then dried and passed through a 200-mesh sieve to obtain Y2O3 nanoparticles. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank diameter is 12 mm, the molding pressure is 15 MPa, and the holding pressure is 8 s. Then, (Y) is added. 0.97 Zn 0.03 )2O3-(Mg 0.75 Zn 0.25 Y₂O₃ nanoparticles are first added, and the molding pressure is 18 MPa for 8 seconds. Then, Y₂O₃ nanoparticles are added, and the molding pressure is increased to 800 MPa for 300 seconds to obtain a ceramic green body with a composite structure. This ceramic green body includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 0.97 Zn 0.03 )2O3-(Mg 0.75 Zn 0.25 Step 9: Place the ceramic blank on a Y2O3 pad and perform double-sided laser sintering on the ceramic blank using a laser to obtain a composite structure ceramic. The laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 10 mm. The preheating irradiation time of the ceramic blank is 100 s, and the laser power is increased to 90 W; the heating irradiation time of the ceramic blank is 250 s, and the laser power is increased to 280 W; the cooling irradiation time is 120 s, and the laser power is reduced to 20 W. No annealing is required. The upper and lower surface layers of the composite structure ceramic are removed by grinding to obtain (Y2O3) composite structure ceramic. 0.97 Zn 0.03 )2O3-(Mg 0.75 Zn 0.25 Infrared transparent ceramic material.

[0036] After observation, the (Y) prepared in Example 2 of this study was obtained 0.97 Zn 0.03 )2O3-(Mg 0.75 Zn 0.25 The main structural properties of the infrared transparent ceramic material are similar to those in Example 1, with a near-infrared cutoff wavelength of 920 nm, an average grain size of 117 nm, and a characteristic flexural strength of 418 MPa. (See...) Figure 6Since laser sintering can effectively avoid contamination of graphite molds, the samples prepared in this embodiment can withstand CO3 at medium wavelengths (6-10 μm). 2- Absorption is relatively weak.

[0037] Compared to Example 2, Comparative Example 1 has a lower concentration of Zn. 2+ It only entered the MgO lattice and not the Y2O3 lattice. Therefore, the Y2O3-(MgO) prepared in Comparative Example 1... 0.75 Zn 0.25 The O ceramic has a grain size of 143 nm, a near-infrared cutoff wavelength of 937 nm, and a characteristic flexural strength of 395 MPa.

[0038] Example 3 An infrared transparent ceramic material with a wide transmission band, its chemical formula is (Y 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 O; The above-mentioned method for preparing infrared transparent ceramic materials includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 0.75 Mn 0.25 )O weighing Y 3+ Compounds, Mg 2+ The compound and Mn with a molar percentage of 25% 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare the corresponding raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix it with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it to obtain precursor powder. The calcination temperature is 240°C and the calcination time is 6 h. Step 4: The precursor powder obtained in Step 3 is calcined in a muffle furnace to obtain primary Y2O3-(Mg) 0.75 Mn 0.25 O powder was calcined at 1100°C for 10 hours, with a precursor powder mass-to-muffle furnace volume loading coefficient of 7.0 kg / m³. 3 ; Step 5: Place the powder obtained in Step 4 and the binder (i.e., oleic acid polyoxyethylene ester) into a ball mill jar, and add 0.8% (molar percentage) of Mn. 2+The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added for planetary ball milling. The mass ratio of powder to anhydrous ethanol was 1:2, the ball milling speed was 180 r / min, and the ball milling time was 24 h. Step 6: Dry the slurry from ball milling in Step 5 at 60 °C for 24 h. Then, pulverize the dried slurry, pass it through a 200-mesh sieve, and subsequently calcine it in a muffle furnace at 800 °C for 5 h to obtain (Y). 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 )O; Step 7: Yttrium oxide powder, sintering aid (ZrO2) and solvent (anhydrous ethanol) are placed in a ball milling device containing ball milling media (ZrO2) for ball milling to obtain a ball-milled slurry; the ball-milled slurry is then dried and passed through a 200-mesh sieve to obtain Y2O3 nanoparticles. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank diameter is 20 mm, the molding pressure is 20 MPa, and the holding pressure is 10 s. Then, (Y) is added. 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 Y₂O₃ nanoparticles are first added, and the molding pressure is 15 MPa for 10 s. Then, Y₂O₃ nanoparticles are added, and the molding pressure is increased to 1200 MPa for 400 s to obtain a ceramic green body with a composite structure. This ceramic green body includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 )O; Step 9: Place the ceramic blank on a Y2O3 pad and perform double-sided laser sintering on the ceramic blank using a laser to obtain a composite structure ceramic. The laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 16 mm. The preheating irradiation time of the ceramic blank is 150 s, and the laser power is increased to 90 W; the heating irradiation time of the ceramic blank is 250 s, and the laser power is increased to 300 W; the cooling irradiation time is 150 s, and the laser power is reduced to 100 W. No annealing is required. The upper and lower surface layers of the composite structure ceramic are removed by grinding, followed by double-sided polishing to obtain (Y2O3) composite structure ceramic. 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 Infrared transparent ceramic material.

[0039] See Figure 7 The infrared transparent ceramic material prepared in this embodiment contains Mn ions 2p 3 / 2 The X-ray photoelectron spectrum of the orbit, with XPS envelope peaks at 640 and 651 eV, corresponds to Mn. 2+ The characteristic peaks indicate that Mn ions were fully reduced to Mn. 2+ .

[0040] Figure 8 Electron paramagnetic resonance (EPR) spectra of infrared transparent ceramic materials prepared by different sintering methods (meaning everything else is the same except for the sintering method) are compared with those obtained by the conventional "air pre-firing + hot isostatic pressing" method. The EPR spectra of the materials prepared by laser sintering in this embodiment are shown in the image. 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 Infrared transparent ceramic materials exhibit distinct and typical Mn content. 2+ The six-peak fine structure demonstrates that laser sintering has a better ability to maintain Mn 2+ The effect of valence state, while the (Y) prepared by conventional sintering method 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 O ceramics Mn 2+ The significant decrease in the sextet peak indicates that Mn 2+ It did not remain divalent. Because Mn 2+ The abnormal valence state of Y makes it difficult for it to dissolve into the MgO phase, resulting in the unsatisfactory (Y) valence state obtained by conventional sintering. 0.992 Mn 0.008 )2O3-(Mg 0.75 Mn 0.25 Infrared transparent ceramics have low transmittance and exhibit a redshift phenomenon in the infrared cutoff wavelength.

[0041] See Figure 9 In this embodiment, the near-infrared cutoff wavelength of the infrared transparent ceramic material is 841 nm. Other main structural properties were observed to be similar to those in Example 1, with an average grain size of 117 nm and a characteristic flexural strength of 420 MPa.

[0042] Example 4 An infrared transparent ceramic material with a wide transmission band, its chemical formula is (Y 0.99 Mn 0.01 )2O3-(Mg 0.72 Mn 0.28 O; The above-mentioned method for preparing infrared transparent ceramic materials includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 0.72 Mn 0.28 )O weighing Y 3+ Compounds, Mg 2+ The compound and Mn with a molar percentage of 28% 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare the corresponding raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix the transparent solution with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it to obtain precursor powder. The calcination temperature is 220°C and the calcination time is 56 h. Step 4: The precursor powder obtained in Step 3 is calcined in a muffle furnace to obtain primary Y2O3-(Mg) 0.72 Mn 0.28 O powder, calcined at 1050°C for 6 hours; Step 5: Place the powder and binder (i.e., oleic acid polyoxyethylene ester) obtained in Step 4 into a ball mill jar, and add 1% Re (molar percentage). 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added for planetary ball milling. The mass ratio of powder to anhydrous ethanol was 1:1.5, the ball milling speed was 180 r / min, and the ball milling time was 20 h. Step 6: Dry the slurry from ball milling in Step 5 at 55 °C for 15 h. Then, pulverize the dried slurry, pass it through a 200-mesh sieve, and then calcine it in a muffle furnace at 700 °C for 3 h to obtain (Y). 0.99 Mn 0.01 )2O3-(Mg 0.72 Mn 0.28 O powder; Step 7: Yttrium oxide powder, sintering aid (ZrO2) and solvent (anhydrous ethanol) are placed in a ball milling device containing ball milling media (ZrO2) for ball milling to obtain a ball-milled slurry; the stirred slurry is then dried and sieved to obtain Y2O3 nanoparticles. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank diameter is 14 mm, the molding pressure is 10 MPa, and the holding pressure is 7 s. Then, (Y) is added. 0.99 Mn 0.01 )2O3-(Mg 0.72 Mn 0.28Y₂O₃ nanoparticles are first added, and the molding pressure is 10 MPa for 7 seconds. Then, Y₂O₃ nanoparticles are added, and the molding pressure is increased to 1000 MPa for 300 seconds to obtain a ceramic green body with a composite structure. This ceramic green body includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 0.99 Mn 0.01 )2O3-(Mg 0.72 Mn 0.28 O; Step 9: Place the ceramic blank on a Y2O3 pad and perform double-sided laser sintering on the ceramic blank using a laser to obtain a composite structure ceramic. The laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 14 mm. The preheating irradiation time of the ceramic blank is 150 s, and the laser power is increased to 100 W; the heating irradiation time of the ceramic blank is 300 s, and the laser power is increased to 350 W; the cooling irradiation time is 120 s, and the laser power is reduced to 50 W. No annealing is required. The upper and lower surface layers of the composite structure ceramic are removed by grinding, followed by double-sided polishing to obtain (Y2O3) composite structure ceramic. 0.99 Mn 0.01 )2O3-(Mg 0.72 Mn 0.28 Infrared transparent ceramic material.

[0043] See Figure 10 The XRD-refined cell parameters of the infrared transparent ceramic material prepared in Example 4 show that the cell parameters of Y2O3 change with Mn. 2+ The doping concentration increases and decreases, which is due to the six-coordinate Mn 2+ The ionic radius is 0.67 Å, ​​which is smaller than that of Y. 3+ The ionic radius (0.94 Å) of MgO leads to the change in the unit cell parameters of Mn. 2+ The doping concentration increases and decreases, which is due to the decrease in Mn content. 2+ The radius (0.67 Å) is greater than that of Mg. 2+ The small radius (0.72 Å) indicates that Mn 2+ They enter the Y₂O₃ and MgO lattices respectively.

[0044] Observations showed that the main structural properties of the infrared transparent ceramic material prepared in Example 4 were similar to those in Example 3, with a near-infrared cutoff wavelength of 835 nm, an average grain size of 135 nm, and a characteristic flexural strength of 415 MPa. (See...) Figure 11Compared with Example 4, in Comparative Example 2, since no binder oleic acid polyoxyethylene ester was added, the powder was not sufficiently lubricated during the molding process, resulting in particle agglomeration and thus larger grain aggregation, which easily leads to stress concentration. Therefore, the characteristic flexural strength of the sample prepared in Comparative Example 2 was 330 MPa.

[0045] Example 5 An infrared transparent ceramic material with a wide transmission band, its chemical formula is (Y 0.975 Ni 0.025 )2O3-(Mg 0.85 Ni 0.15 O; The above-mentioned method for preparing infrared transparent ceramic materials includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 0.85 Ni 0.15 )O weighing Y 3+ compounds, Mg 2+ The compound and Ni with a molar percentage of 15% 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare the corresponding raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix it with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it to obtain precursor powder. The calcination temperature is 240°C and the calcination time is 6 h. Step 4: The precursor powder obtained in Step 3 is calcined in a muffle furnace to obtain primary Y2O3-(Mg) 0.85 Ni 0.15 O powder was calcined at 950°C for 10 hours, with a precursor powder mass-to-muffle furnace volume loading coefficient of 1.5 kg / m³. 3 ; Step 5: Place the powder and binder (i.e., oleic acid polyoxyethylene ester) obtained in Step 4 into a ball mill jar, and add Ni at a molar percentage of 2.5%. 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added for planetary ball milling. The mass ratio of powder to anhydrous ethanol was 1:2, the ball milling speed was 180 r / min, and the ball milling time was 24 h. Step 6: The slurry obtained after ball milling in Step 5 is dried at 55 °C for 18 h. The dried slurry is then pulverized, passed through a 200-mesh sieve, and subsequently calcined in a muffle furnace at 700 °C for 5 h to obtain (Y). 0.975 Ni0.025 )2O3-(Mg 0.85 Ni 0.15 O powder; Step 7: Yttrium oxide powder, sintering aid (ZrO2) and solvent (anhydrous ethanol) are placed in a ball milling device containing ball milling media (ZrO2) for ball milling to obtain a ball-milled slurry; the ball-milled slurry is then dried and passed through a 200-mesh sieve to obtain Y2O3 nanoparticles. Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding. The blank diameter is 18 mm, the molding pressure is 16 MPa, and the holding pressure is 7 s. Then, (Y) is added. 0.975 Ni 0.025 )2O3-(Mg 0.85 Ni 0.15 Y₂O₃ nanoparticles are first added, and the molding pressure is 15 MPa for 7 seconds. Then, Y₂O₃ nanoparticles are added, and the molding pressure is increased to 900 MPa for 250 seconds to obtain a ceramic green body with a composite structure. This ceramic green body includes a core layer and surface layers formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 0.975 Ni 0.025 )2O3-(Mg 0.85 Ni 0.15 O; Step 9: Place the ceramic green body on a Y2O3 pad and perform double-sided laser sintering on the ceramic green body using a laser to obtain a composite structure ceramic. The laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 10 mm. The preheating irradiation time of the ceramic green body is 120 s, and the laser power is increased to 95 W; the heating irradiation time of the ceramic green body is 300 s, and the laser power is increased to 50 W; the cooling irradiation time is 120 s, and the laser power is reduced to 60 W. No annealing is required. The upper and lower surface layers of the composite structure ceramic are removed by grinding to obtain (Y2O3) composite structure ceramic. 0.975 Ni 0.025 )2O3-(Mg 0.85 Ni 0.15 Infrared transparent ceramic material.

[0046] See Figure 12 The main structural properties of the infrared transparent ceramic material prepared in Example 5 are similar to those in Example 1, as observed by the test: a near-infrared cutoff wavelength of 925 nm, an average grain size of 147 nm, and a characteristic flexural strength of 435 MPa. This is because NiO has a coefficient of thermal expansion of 14.0 × 10⁻⁶. -6 / K, which is greater than the thermal expansion coefficient of MgO by 13×10. -6 / K. This leads to (Mg) 0.85 Ni0.15 )O phase and (Y 0.975 Ni 0.025 The difference between the thermal expansion coefficients of the 2O3 phases further increases ((Y) 0.975 Ni 0.025 Since the effect of a small amount of NiO in 2O3 on the coefficient of thermal expansion is negligible, the risk of cracking due to inconsistent shrinkage caused by the large difference in the coefficient of thermal expansion of infrared transparent ceramics during sintering is also increased. In this embodiment, a multi-layer composite structure is first fabricated. The yttrium oxide ceramic layer on the upper and lower surfaces can act as a "bonding layer" to avoid cracking of the internal multiphase ceramics due to inconsistent coefficients of thermal expansion.

[0047] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Any simple changes or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the scope of the technology disclosed in the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing an infrared transparent ceramic material with a wide transmission band, characterized in that, The chemical formula of the infrared transparent ceramic material is (Y 1-x Re x )2O3-(Mg 1-y Re y )O, where 0 < x <4%; 0< y <30%; Re=Zn 2+ Mn 2+ Ni 2+ One of them; The preparation method of the infrared transparent ceramic material includes the following steps: Step 1, according to the chemical formula Y2O3-(Mg 1-y Re y )O weighing Y 3+ Compounds, Mg 2+ The compounds and their molar percentages are y Re 2+ The compound was used as a raw material, and the raw material was dissolved in deionized water to prepare a raw material solution; Step 2: Dissolve citric acid and ethylene glycol in deionized water, heat and stir until a transparent solution is formed, and mix the transparent solution with the raw material solution obtained in Step 1 to obtain the precursor solution; Step 3: Place the precursor solution obtained in Step 2 in an oven and calcine it at 180~240°C for 3~6 h to obtain precursor powder; Step 4: Place the precursor powder obtained in Step 3 in a muffle furnace and calcine it at 900~1100°C for 5~10 h to obtain primary Y2O3-(Mg 1-y Re y )O powder; Step 5, the primary Y2O3-(Mg) obtained in step 4 1-y Re y The O powder and binder were placed in a ball mill jar, and the molar percentage of the added powder was 1. x Re 2+ The compound was dissolved in a solution prepared with deionized water, anhydrous ethanol was added as a solvent, and grinding balls were added. The mixture was then subjected to planetary ball milling at a ball milling speed of 120-180 r / min for 12-24 h to obtain a slurry, in which the primary Y2O3-(Mg) 1-y Re y The mass ratio of O powder to anhydrous ethanol is 1:1 to 1:

2. Step 6: Dry the slurry obtained after ball milling in Step 5 at 40-60 °C for 10-24 h. Then, pulverize the dried slurry, pass it through a 100-200 mesh sieve, and then calcine it in a muffle furnace at 500-800 °C for 2-5 h to obtain (Y). 1-x Re x )2O3-(Mg 1-y Re y O powder; Step 7: Place yttrium oxide powder, sintering aid and solvent in a ball milling device containing ball milling media for ball milling, and dry and sieve the ball milled slurry in sequence to obtain Y2O3 nano powder; Step 8: The Y2O3 nanopowder obtained in Step 7 is subjected to equiaxed biaxial pressure molding, with a blank diameter of 8~20 mm and a molding pressure of 10~20 MPa. Then, (Y...) 1-x Re x )2O3-(Mg 1-y Re y Y₂O₃ nanoparticles are first added, and then Y₂O₃ nanoparticles are added. The molding pressure is 10-20 MPa, and the final molding pressure is 500-1200 MPa. The holding time is 200-400 s, resulting in a ceramic green body with a composite structure. The ceramic green body with the composite structure includes a core layer and a surface layer formed on the upper and lower surfaces of the core layer. The surface layer is made of Y₂O₃, and the core layer is made of (Y₂O₃)₂O₃ nanoparticles. 1-x Re x )2O3-(Mg 1-y Re y O; Step 9: Place the ceramic blank on a Y2O3 pad and perform double-sided laser sintering on the ceramic blank using a laser to obtain a composite structure ceramic. The upper and lower surface layers of the composite ceramic structure are removed, and double-sided polishing is performed to obtain the infrared transparent ceramic material.

2. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, In step 4, the mass-volume loading coefficient corresponding to the precursor powder mass and the muffle furnace volume is 1.5~8.0 kg / m³. 3 .

3. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, In step 5, the binder is oleic acid polyoxyethylene ester, and the amount of binder added is primary Y2O3-(Mg 1-y Re y 0.4%~1.2% of the mass of O powder.

4. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, In step 9, the laser is a CO2 laser with a wavelength of 10.6 μm and a spot diameter of 5~16 mm. Laser sintering consists of two stages: a preheating stage and a heating stage. The preheating irradiation time for the ceramic blank is 80-150 s, and the laser power is 80-100 W. The heating irradiation time for the ceramic blank is 200-300 s, and the laser power is 250-350 W. After the laser sintering is completed, the cooling stage begins, specifically by controlling the laser irradiation time to 100-150 seconds and reducing the laser power to 0-100 W.

5. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, x=0.008,y=0.25,Re=Mn 2+ 。 6. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, In step 8, the thickness of the core layer is 1~6 mm, the thickness of the surface layer is 0.5~2 mm, and the thickness ratio of the upper surface layer, the core layer and the lower surface layer is 1:3:1~1:2:

1.

7. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, The near-infrared cutoff wavelength of the infrared transparent ceramic material is 835~984 nm, and the near-infrared cutoff wavelength refers to the incident light wavelength when the ceramic transmittance is 10%.

8. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, The average grain size of the infrared transparent ceramic material is 117~147 nm.

9. The method for preparing an infrared transparent ceramic material with a wide transmission band according to claim 1, characterized in that, The characteristic flexural strength of the infrared transparent ceramic material is 415~435 MPa.

10. An infrared transparent ceramic material with a wide transmission band, characterized in that, The infrared transparent ceramic material is prepared by the preparation method described in any one of claims 1 to 9.

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