Preparation method of high-density bulk polycrystalline albite aggregate under high temperature and high pressure conditions

Abstract

This invention discloses a method for preparing high-density bulk polycrystalline albite polymers under high temperature and high pressure conditions, comprising: completely sealing albite sample powder under a vacuum of 10... –3 The steel cladding was placed inside the graphite furnace cylinder of the high-pressure vessel of a hot isostatic pressing (HIP) apparatus, and a graphite sealing cap was placed on top. Argon gas was used as the pressure transmission medium. The temperature inside the sample chamber of the cylinder was raised to 1050 °C and the pressure was raised to 93.2 MPa using a multi-gradient cylinder heating and pressurization method, and the temperature and pressure were maintained for 7.9 hours. The temperature inside the sample chamber of the cylinder was lowered to 162 °C and the pressure was lowered to 50.7 MPa at a cooling rate of 16.44 °C / min and a depressurization rate of 0.79 MPa / min. Finally, the pressure was released and the sample was cooled to room temperature to obtain polycrystalline albite polymer. This method fills the technical gap in the preparation of bulk experimental samples of high-density polycrystalline albite polymer under high temperature and high pressure conditions.

Description

Technical Field

[0001] This invention belongs to the field of experimental sample synthesis technology of plagioclase series oxygen-containing salt mineral polymers with bulk framework structure – polycrystalline alkali metal aluminosilicate minerals, and particularly relates to a method for preparing high-density bulk polycrystalline albite polymers under high temperature and high pressure conditions. Background Technology

[0002] Dyke rocks refer to a large class of igneous rocks that exist independently of intrusive and extrusive igneous rocks, occurring in vein-like geological structures such as conical, banded, radial, dendritic, dike-like, and bed-like formations, filling the fissures of geological structures. Typically, naturally exposed vein-like geological formations are called vein bodies, whose length is much greater than their width, extending for tens of kilometers, and are mostly shallow to shallow intrusive rocks. Ganges closely related to the genesis of intrusive rock bodies are mostly distributed within the rock body or near the surrounding rocks; while ganges closely related to the genesis of deep faults are mostly regionally distributed. According to the mineral types and chemical composition contained in the gangue, it is mainly divided into: (1) gangue with similar composition to plutonic rocks. This type of gangue is also called undivided gangue or inherited gangue. Typical rocks include: microcrystalline diorite, granite porphyry, diabase, diorite porphyry, etc.; (2) gangue with a huge difference in composition from plutonic rocks. This type of gangue is also called divided gangue. If the rock-forming minerals contained in the gangue are mainly light-colored minerals and have a pegmatitic structure, it is called pegmatite; if the rock-forming minerals contained in the gangue are mainly light-colored minerals and have a fine-grained structure, it is called aspirin; if the rock-forming minerals contained in the gangue are mainly dark-colored minerals and have a lamprophyre structure, it is called lamprophyre.

[0003] As important vein rocks, pegmatites refer to various types of coarse-grained to macrograined vein-like bodies and massive bodies. Geologists classify pegmatites mainly into granite pegmatites, gabbro pegmatites, diorite pegmatites, and syenite pegmatites based on the similarity of their main mineral composition to that of intrusive rocks. Granite pegmatites, which are similar in rock composition to granite, can be further subdivided into simple pegmatites and complex pegmatites. Typically, the main rock-forming minerals in pegmatites are albite, potassium feldspar, and quartz, and sometimes they may contain flaky biotite, muscovite, spodumene, tourmaline, and other accessory or impurity minerals. Metasomatism is not significant. Albite is the most important rock-forming mineral in natural granite pegmatites, with a much higher content than potassium feldspar (or microcline). Albite samples often contain small amounts of associated / symbiotic impurities such as quartz, muscovite, pyrite, strontium carbonate, nepheline, amphibole, jadeite, omphacite, chromite, and hematite. Albite is the most abundant sodium-rich plagioclase series mineral in the Earth's crust and a core raw material for modern industries (ceramics, glass). Furthermore, based on the crystal morphology of the rock-forming minerals, geological genesis, and associated mineral assemblages, geologists classify granite pegmatites into massive structural granite pegmatites, fully differentiated granite pegmatites, rare metal metasomatic granite pegmatites, and albite-spodumene type granite pegmatites. Existing field geological data studies indicate that numerous mineral resources of extremely important industrial value, such as rare metal thallium deposits, rare element lithium deposits, mica deposits, rare metal niobium deposits, rare earth element fluorocarbon calcium cerium deposits, crystal deposits, albite deposits, rare metal beryllium deposits, and rare earth element fluorocarbon cerium deposits, are all closely related to pegmatite intrusions in terms of their geological genesis. In recent years, geologists have conducted extensive research on the geological genesis and material origin of pegmatites, and have proposed three important academic viewpoints: (1) Magmatic geological genesis: pegmatites are formed by the intrusion of magma into the fissures of the rock mass, followed by metasomatic or crystallization differentiation processes; (2) Metasomatic genesis: granites are formed by recrystallization or metasomatic processes under hydrothermal or vapor-water processes; (3) Magmatic-metastomotic genesis: after crystallization, pegmatites are subjected to metasomatic processes again by late-stage solutions from deep magma, resulting in the formation of rare metal and rare earth metal mineralization in the pegmatites. It is believed that pegmatites are products of co-crystallization of granitic melts. Therefore, in granitic pegmatites, metasomatic processes such as saccharin-like albite alteration, pyroalloy alteration, and greisenization are relatively common.

[0004] To investigate the formation mechanisms and occurrence principles of common geological disasters deep within the Earth, such as volcanoes, earthquakes, and debris flows, geologists typically employ high-pressure equipment with multiple large cavities, including hydrothermal autoclaves, piston cylinder presses, and rotary shear friction testing machines, to conduct simulation experiments on the solubility, friction coefficient, shear stress, and other physical parameters of large-volume polycrystalline albite aggregates under high temperature and pressure conditions. Obtaining a large-sized polycrystalline albite aggregate sample (46.79 mm in diameter × 70.19 mm in height) is a crucial step in simulating these physical properties under high temperature and pressure conditions. Geologists typically use naturally occurring albite found in the field as a substitute for polycrystalline albite aggregates in their experimental samples. However, natural albite samples often suffer from low density, contain numerous impurities (such as various oxide minerals like quartz, muscovite, pyrite, strontium carbonate, nepheline, amphibole, jadeite, omphacite, chromite, and hematite, as well as hydrous layered aluminosilicate minerals, metal sulfide minerals, carbonate minerals, framework silicate minerals, chain silicate minerals, and spinel group minerals), and have relatively large and unevenly distributed albite single crystals, which are the main constituent minerals. Due to numerous insurmountable drawbacks, such as the difficulty in eliminating the optimal orientation of the crystal lattice and the obvious anisotropy of the crystal axis, many different high-temperature and high-pressure mineral and rock property simulation teams around the world use natural albite as the initial sample and employ multi-faceted large-cavity high-pressure equipment such as hydrothermal autoclaves, piston cylinder presses, and rotary shear friction testers. However, the experimental data on the physical properties of natural albite under high-temperature and high-pressure conditions obtained show significant differences, making it difficult to widely apply these experimental results to the interpretation of the formation mechanisms and occurrence mechanisms of geological disasters such as volcanoes, earthquakes, and debris flows.

[0005] Compared with existing technologies, artificially synthesized island-shaped silicate mineral single crystal experimental samples can be prepared under high temperature and high pressure conditions using quasi-hydrostatic presses such as YJ-3000t and Kawai-1000t, as shown in patent {Dai Lidong and Hu Haiying. Chinese National Invention Patent: A method for preparing low-titanium dry forsterite single crystals under high temperature and high pressure conditions. Patent No.: ZL202111317925.5}. However, this method is limited to preparing island-shaped silicate mineral single crystal experimental samples rather than polycrystalline aggregate samples. The obtained island-shaped silicate mineral single crystals have a particle size ranging from 100 micrometers to 425 micrometers, and the particle size distribution is uneven. The size of the obtained single crystal minerals is severely limited by the sample chamber volume. The cylindrical sample size of the high temperature and high pressure experimental product—single crystal island-shaped silicate minerals—obtained by this method does not exceed 6 mm (bottom diameter) × 6 mm (height). Therefore, the size of the artificially synthesized island-shaped silicate mineral samples cannot meet the requirements for simulating the physical properties of minerals and rocks under high temperature and high pressure conditions in large blocks. Although existing techniques, using quasi-hydrostatic presses such as the YJ-3000t and Kawai-1000t, produce samples only a few millimeters in size, they are a relatively effective method for synthesizing single-crystal mineral samples under high temperature, high pressure, and quasi-hydrostatic conditions. However, when this method is applied to the synthesis of bulk polycrystalline albite aggregate samples (e.g., with a diameter greater than 40 mm), significant asymmetric shrinkage inevitably occurs at the top and bottom of the albite sample powder during the high temperature, high pressure, and quasi-hydrostatic experiments due to unidirectional compression. This results in numerous macroscopic voids and defects during the preparation of bulk polycrystalline mineral aggregate samples. These macroscopic voids and defects cause wrinkles or pores in the central part of the cross-section of the bulk polycrystalline albite aggregate, ultimately making it easy for the sample to undergo severe porosity or aggregation along the center of the wrinkles or pores. This is the unavoidable shrinkage and porosity effect during the synthesis of bulk polycrystalline mineral aggregate samples under high temperature, high pressure, and quasi-hydrostatic conditions. The shrinkage and porosity effects of these polycrystalline albite aggregate samples lead to severe excessive deformation, resulting in numerous voids, fracture wrinkles, and cavities in the prepared bulk polycrystalline albite aggregate samples. This significantly affects the preparation results of bulk polycrystalline albite aggregate samples. Therefore, neither natural albite nor small-sized (no more than 6 mm) albite single crystal samples obtained in the laboratory can meet the minimum experimental sample size requirements for mineral and rock property simulation on multi-faceted, large-cavity high-pressure equipment such as hydrothermal autoclaves, piston cylinder presses, and rotary shear friction testing machines. To date, there is still no effective synthesis method.Therefore, it is particularly urgent to effectively synthesize a high-density, high-compactness, high-purity, and large-volume polycrystalline albite aggregate experimental sample that meets the needs of various high-temperature and high-pressure laboratory simulations in earth science research, especially for experimental simulation studies of the physical properties of large-volume framework-structured plagioclase series oxygen-containing salt mineral aggregates—polycrystalline alkali metal aluminosilicate minerals and rocks—under high-temperature and high-pressure conditions, such as solubility, friction coefficient, and shear stress. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a method for preparing high-density bulk polycrystalline albite aggregates under high temperature and high pressure conditions, thereby filling the technical gap in the preparation of bulk experimental samples of high-density polycrystalline albite aggregates under high temperature and high pressure conditions. This method aims to obtain bulk high-density polycrystalline albite aggregate experimental samples, providing important experimental sample support for the experimental simulation study of the solubility, friction coefficient, and shear stress of bulk framework-structured plagioclase series oxygen-containing salt mineral aggregates—polycrystalline alkali metal aluminosilicate minerals and rocks—under high temperature and high pressure conditions on multi-faceted large-cavity high-pressure equipment such as hydrothermal autoclaves, piston cylinder presses, and rotary shear friction testers.

[0007] Technical solution of the present invention:

[0008] A method for preparing high-density bulk polycrystalline albite polymers under high temperature and high pressure conditions includes: completely sealing albite sample powder under a vacuum of 10... –3 The steel cladding was placed inside the graphite furnace cylinder of the high-pressure vessel of a hot isostatic pressing (HIP) apparatus, and a graphite sealing cap was placed on top. Argon gas was used as the pressure transmission medium. The temperature inside the sample chamber of the cylinder was raised to 1050 °C and the pressure was raised to 93.2 MPa using a multi-gradient cylinder heating and pressurization method, and the temperature and pressure were maintained for 7.9 hours. The temperature inside the sample chamber of the cylinder was lowered to 162 °C and the pressure was reduced to 50.7 MPa at a cooling rate of 16.44 °C / min and a depressurization rate of 0.79 MPa / min. Finally, the pressure was released and the temperature was cooled to room temperature to obtain polycrystalline albite polymer.

[0009] The method of raising the temperature to 1050 °C and the pressure to 93.2 MPa within the cylinder sample chamber using a multi-gradient cylinder heating and pressurization approach includes: raising the temperature to 600 °C and the pressure to 70.4 MPa within the temperature range of room temperature to 600 °C using a heating rate of 18.3 °C / min and a pressurization rate of 0.76 MPa / min; raising the temperature to 900 °C and the pressure to 84.5 MPa within the temperature range of 600 °C to 900 °C using a heating rate of 10 °C / min and a pressurization rate of 0.47 MPa / min within the temperature range of 900 °C to 1050 °C using a heating rate of 7.5 °C / min and a pressurization rate of 0.44 MPa / min within the temperature range of 900 °C to 1050 °C using a pressurization rate of 0.44 MPa / min within the temperature range of 900 °C to 1050 °C using a heating rate of 7.5 °C / min and a pressurization rate of 0.44 MPa / min within the temperature range of 1050 °C to 93.2 MPa.

[0010] Beneficial effects of this invention:

[0011] This invention organically combines general geology, magmatic petrology, crystallography, dynamics of Earth's structural evolution, ore field tectonic geology, crystal defect chemistry, meteoritics and Earth's origin, engineering geology, optical mineralogy, isotope geochemistry, genetic mineralogy, mining geology, introduction to geophysics, rock mechanics, mineralogy, petrography, geochemistry, ore deposit geology, mineral resource geology, sedimentary petrology, metamorphic petrology, regional field geology, structural geology, stratigraphy, geochronology, and experimental petrology. With a background in Earth science disciplines such as geochemistry, ore genesis, rock rheology, geodynamics, hot isostatic pressing, hot isostatic powder metallurgy, seismology, igneous magmatism, high-pressure rheology, mineral physics, deep Earth science, high-pressure materials science, materials science, and high-pressure experimental mineralogy, large-volume, highly dense polycrystalline albite aggregate experimental samples were prepared under high temperature and high pressure conditions using an RD80×100‒2000–200 double 2000 type hot isostatic pressing equipment.

[0012] The initial raw material selected for this invention is gem-quality single-crystal albite particles collected in the field, which are crushed into uniform mineral single-crystal powder. The powder is placed in a steel sheath and subjected to a series of processes including compaction, vacuuming, high-temperature degassing, high-temperature vacuum welding, argon filling, and furnace washing to ensure that the albite sample powder is in a completely sealed environment protected by argon inert gas. The steel sheath containing the albite sample powder is placed in the sample chamber of an RD80×100‒2000–200 double 2000 type hot isostatic pressing equipment, and sintered under high temperature and high pressure to form a large-volume, highly dense polycrystalline albite aggregate. The prepared polycrystalline albite aggregate sample can be widely used in the experimental simulation research of diagenesis and mineralization of mineral and rock physicochemical properties under high temperature and high pressure conditions.

[0013] The steel sheath used in the hot isostatic pressing (HIP) experiment of this invention has the following dimensions: 57.02 mm (outer diameter) × 84.78 mm (height) × 3 mm (wall thickness). This allows for the production of large-sized polycrystalline albite polymer samples with a diameter of up to 46.79 mm and a height of up to 70.19 mm. During the HIP experiment on the polycrystalline albite polymer samples under high temperature and high pressure conditions, inert argon gas is used as the pressure transmission medium. By increasing the temperature and compressing the inert argon gas, uniform pressure and temperature are applied to the albite sample powder in all directions, effectively avoiding the adverse effects of shrinkage cavities and porosity during the HIP experiment. The inert argon gas ensures complete isolation between the albite sample powder and air within the sample chamber, effectively preventing redox reactions between the albite sample powder and air during the HIP experiment. Furthermore, this invention avoids the traditional high-pressure chemical reaction method, which may introduce excessive chemical reagents during the preparation of polycrystalline albite polymer samples, potentially leading to the introduction of impurity ions.

[0014] This invention employs a multi-gradient hot isostatic pressing (HIP) process, first increasing pressure and then temperature, to prepare polycrystalline albite aggregate experimental samples with excellent physicochemical properties such as fine crystal size, high density, and high purity. This breakthrough overcomes the technical bottleneck of synthesizing large-volume experimental samples of high-density polycrystalline albite aggregates. Furthermore, this invention's multi-gradient HIP process is not limited by the shape or size of the sample, allowing for the preparation of complex polycrystalline mineral samples with irregular shapes. Compared to existing technologies that use quasi-hydrostatic presses such as the YJ-3000t and Kawai-1000t to prepare artificially synthesized island-shaped silicate mineral single crystals under high temperature and high pressure conditions, this invention's multi-gradient HIP process can obtain polycrystalline albite aggregate experimental samples with near-theoretical density and extremely high sample strength.

[0015] This invention, based on an RD80×100‒2000–200 double 2000-type hot isostatic pressing (HIP) device, employs a multi-gradient HIP molding process involving first increasing pressure and then increasing temperature. For the first time, it yields large-volume, uniformly distributed, high-density, highly compact, and high-strength polycrystalline albite aggregate experimental samples under conditions of 93.2 MPa and 1050 °C. These samples can be widely applied to high-pressure equipment with multiple large cavities, such as hydrothermal autoclaves, piston cylinder presses, and rotary shear friction testing machines, to simulate the solubility, friction coefficient, and shear stress of large-volume framework-structured plagioclase series oxygen-containing salt mineral aggregates—polycrystalline alkali metal aluminosilicate mineral rocks—under high temperature and high pressure conditions. This provides crucial experimental sample support for systematically exploring the formation mechanisms and occurrence mechanisms of common geological disasters such as deep-earth volcanoes, earthquakes, and debris flows. Attached Figure Description

[0016] Figure 1 To utilize the RD80×100‒2000–200 double 2000 type hot isostatic pressing equipment, and adopt a multi-gradient hot isostatic pressing molding process of first increasing pressure and then increasing temperature, the temperature and pressure in the sample chamber during the preparation of polycrystalline albite polymer are shown in the curves of temperature and pressure changes over time.

[0017] Figure 2 To obtain fine-grained albite sample powder by crushing and grinding with the aid of a jaw crusher (model: BB 200) and a high-efficiency Retsch disc vibratory mill (model: RS200), optical microscopic observation results of the albite sample before hot isostatic pressing experiment were obtained using a high-magnification, high-precision Olympus SZX16 research-grade stereomicroscopic imaging platform.

[0018] Figure 3 This document presents the optical microscopic observation results of the surface morphology and particle size distribution of polycrystalline albite polymer samples obtained from hot isostatic pressing experiments at 93.2 MPa and 1050 °C using the high-precision Olympus SZX16 research-grade stereomicroscopic imaging platform. Detailed Implementation

[0019] A method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions, comprising:

[0020] Step 1: Use elongated elliptical albite single crystal mineral particles as the initial sample; use a high-precision Olympus SZX16 research-grade stereomicroscopy imaging platform to accurately measure the particle size of the initial sample. The smallest albite single crystal particle size is 5.4 mm and the largest particle size is 11.3 mm. If the mineral grain size of the albite single crystal is too large, only a low-magnification, high-precision Olympus SZX16 research-grade stereomicroscopy platform can be used for sample selection, making it difficult to accurately identify high-purity albite single crystals that do not contain other symbiotic / associated minerals or impurities. If the mineral grain size of the albite single crystal is too small, it is difficult to effectively separate the albite single crystal from oxide minerals, hydrous layered aluminosilicate minerals, metal sulfide minerals, carbonate minerals, framework silicate minerals, chain silicate minerals, and spinel group minerals of different compositions, such as quartz, muscovite, pyrite, strontium carbonate, nepheline, amphibole, jadeite, omphacite, chromite, and hematite. Furthermore, this invention requires the selection of a relatively large number of mineral single crystals, which will consume a lot of time and manpower.

[0021] Step 2: Place the selected albite single crystal particles on an ultrasonic cleaner and use acetone, alcohol and deionized water as cleaning solutions in sequence for ultrasonic cleaning for 19 minutes to remove impurities from the sample surface.

[0022] Step 3: Using a high-magnification, high-precision Olympus SZX16 research-grade stereomicroscopic imaging platform, carefully select 300 grams of albite single crystal particles with complete crystal form, uniform color, colorless and transparent appearance, fresh surface, and no other impurity minerals. This ensures that the initial sample of albite single crystal particles has high purity before the hot isostatic pressing experiment under high temperature and high pressure conditions.

[0023] Step 4: Place the carefully selected albite single crystal particles in a vacuum drying oven at 200 degrees Celsius for at least 20 hours to completely remove adsorbed water from the sample surface. If the temperature is too low, a certain amount of adsorbed water may adhere to the surface of the albite crystals, making it difficult to accurately weigh the initial sample of albite single crystal particles during further grinding. If the temperature is too high, it may cause the albite single crystals to decompose, ultimately severely affecting the preparation effect of the hot isostatic pressing (HIP) experiment sample under high temperature and high pressure conditions.

[0024] Step 5: Place the initial sample of albite single crystal particles on a jaw crusher (model: BB 200), set the instrument's drive power to 1.5 kW, and use a crushing time of 4 minutes to crush the albite single crystal particles into mineral single crystal particles with a particle size of less than 2 mm. The purpose is to fully crush the sample to obtain albite single crystal particles with a medium particle size (less than 2 mm).

[0025] Step 6: Place the sample on a high-efficiency Retsch disc vibratory mill (model: RS200), using a high-speed mode of 1250 rpm and setting the instrument's drive power to 1.5 kW. Grind the mineral single crystal particles into fine-grained albite mineral powder with a particle size of 13.75 μm to 21.84 μm (see...). Figure 2 The amount of single-crystal albite sample ground in a single cycle is 100 grams, and the grinding time is 8 minutes. Albite powder within this particle size range has a large specific surface area (surface area per unit weight of mineral powder), which significantly increases the contact area between particles due to pressure and temperature. This is more conducive to forming a stronger bonding force between the albite powder particles during the hot isostatic pressing experiment of this invention, thereby greatly improving the compactness and density of the prepared fine-grained polycrystalline albite polymer sample.

[0026] Step 7: Considering that the albite sample powder with a relatively fine particle size is easy to absorb water in the air, it is placed in a paper sealed bag and dried in a vacuum drying oven at 90 degrees Celsius for 23 days to completely remove the adsorbed water on the surface of the sample powder.

[0027] Step 8: In the process of preparing polycrystalline albite polymer samples using an RD80×100‒2000–200 double 2000 type hot isostatic pressing (HIP) apparatus, a sample steel sheath was prepared using low-carbon steel of No. 20 steel. No. 20 steel refers to steel with a carbon content between 0.17% and 0.23%. The low-carbon steel (No. 20 steel) sheath selected in this case has the following main superior properties: (1) The low-carbon steel (No. 20 steel) sheath does not react with the albite sample powder, avoiding contamination of the sample during the HIP experiment and directly affecting the preparation effect; (2) The low-carbon steel (No. 20 steel) sheath can withstand the temperature of 1050 °C and the pressure of 93.2 ppm required for the preparation of polycrystalline albite polymer samples under the HIP conditions of this invention. MPa; (3) The steel sheath material of low carbon steel (20 steel) has good air tightness, which ensures that the sodium feldspar sample powder will not leak under high temperature, high pressure and argon gas pressure transmission medium conditions, and can also ensure the sealing of the steel sheath and the sealing of the weld during the vacuum exhaust process. All these properties are very reliable; (4) The steel sheath of low carbon steel (20 steel) also has excellent properties such as relatively easy edge rolling, cutting, processing, deformation and welding performance.

[0028] This invention selects a continuously cast slab of No. 20 low-carbon steel with a wall thickness of 3 mm as the initial raw material for the steel cladding. After heating it to 200 °C, it is cooled to the set temperature by laminar flow using a roughing mill and a finishing mill. It is then rolled into a steel strip coil by a coiler, and then undergoes multiple hot rolling processes including three rolling and edge trimming to finally obtain the steel cladding for the hot isostatic pressing test of albite sample powder with dimensions of 57.02 mm (outer diameter) × 84.78 mm (height) × 3 mm (wall thickness).

[0029] Similarly, a continuously cast slab of No. 20 low-carbon steel with a wall thickness of 3 mm was selected as the initial raw material for the steel cladding cover. The same hot rolling process was used to prepare the upper and lower sealing covers of the steel cladding. The sleeve, upper and lower sealing covers were welded together by high-temperature vacuum welding to prepare a complete steel cladding for the hot isostatic pressing experiment of albite sample powder.

[0030] Step 9: First, vacuum weld the sleeve and lower sealing cap of the steel cladding. Then, place the dried albite sample powder inside the steel cladding. After a series of processes including compaction, vacuuming, high-temperature degassing, and high-temperature vacuum welding, the albite sample powder is completely sealed in a vacuum of 10... –3 Pa is in the steel ladle sleeve.

[0031] Achieving such a low vacuum level within the steel-clad cavity requires at least 67 hours of evacuation, while simultaneously degassing the sample at 400 °C to ensure the albite powder is completely in a sealed vacuum environment and that all moisture is removed. The albite powder sealed within the steel cladding must be thoroughly compacted. –3 The series of processes, including extremely low vacuum, 400 °C high-temperature degassing, and high-temperature vacuum welding, are mainly aimed at: (1) ensuring that the albite sample powder is fully compacted, which can ensure that a sufficient amount of albite sample powder is sealed in the steel sleeve, which will help increase the density of the polycrystalline albite polymer in the hot isostatic pressing experiment, thereby greatly improving the preparation effect of the final product bulk polycrystalline albite polymer sample; (2) ensuring that the albite sample powder is fully compacted, which can ensure the filling amount of albite sample powder sealed in the steel sleeve, which will help enhance the compactness between albite sample powder particles, effectively avoiding excessive deformation of the sample during the hot isostatic pressing experiment, thereby greatly improving the compactness of the final product bulk polycrystalline albite polymer sample; (3) maintaining 10 –3 The extremely low vacuum of Pa ensures that the steel sheath is easily deformed under high temperature and high pressure, thereby uniformly transmitting the high pressure borne by the steel sheath to the sodium feldspar sample powder sealed inside; (4) Under the condition of 400 °C, the sodium feldspar sample powder is degassed at high temperature, completely removing any water vapor that may be present in the sample powder; (5) The steel sheath is welded by high temperature vacuum, which effectively isolates the welding head from direct contact with air, and the high temperature oxidation of the metal welding point can be completely avoided, which will greatly enhance the sealing performance of the steel sheath.

[0032] Step 10: Carefully place the steel sleeve containing the albite sample powder into the graphite furnace cylinder of the high-pressure vessel of the hot isostatic pressing (HIP) equipment, and cover it with the graphite sealing cap. This invention uses an RD80×100‒2000–200 double 2000-type HIP equipment to densify the albite sample powder under high temperature and high pressure conditions. The graphite furnace cylinder is the core component of this equipment and also the heating element that achieves the extremely high sample chamber temperature of 2000 degrees Celsius.

[0033] Step 11: Turn on the main power switch, dedicated computer automatic program, exhaust fan and argon concentration detection alarm of the RD80×100‒2000–200 dual 2000 type hot isostatic pressing equipment in sequence. Because the hot isostatic pressing (HIP) equipment operates at a power of 30,000 watts per hour, it is an ultra-high-power, high-temperature, and high-pressure instrument. Therefore, to ensure the safety of the experimental operators, the main power switch must be kept off when the equipment is not in operation. To ensure automatic control and arbitrary adjustment of temperature and pressure during HIP experiments, a dedicated computer-controlled software program has been developed for this instrument. A dual-pipeline high-power exhaust system is used to prevent leakage of the inert argon gas pressure transmission medium during the HIP experiment of polycrystalline albite polymer samples under high temperature and pressure. Excessive argon concentration in the operating space could lead to asphyxiation for the operators. A high-sensitivity laboratory-specific argon concentration monitoring alarm is used. Its main purpose is to monitor the argon concentration in the sealed laboratory space during the operation of the HIP equipment in real time. Abnormal changes in argon concentration in the sealed space can also determine the operating status of high-pressure argon in the pipelines and circuits of the high-pressure device, ensuring the absolute safety of the operators during HIP experiments.

[0034] This invention uses argon as an inert gas as the pressure transfer medium. Argon is chosen because it is a colorless, tasteless, odorless, non-toxic, chemically stable, and thermally conductive inert gas. Compared with nitrogen, argon has more stable chemical properties and can completely maintain the chemical composition and process performance of the prepared material, thereby greatly improving the repeatability of the preparation molding process and the reliability of the product performance. However, in the hot isostatic pressing experiment, the main drawbacks of choosing nitrogen as the pressure transfer medium are as follows: (1) Under high temperature and high pressure conditions, nitrogen inevitably reacts with various metals or alloys, especially for samples containing multiple active metals such as titanium, aluminum, and zirconium. The samples will be nitrided, and a nitride layer will be formed on the surface of the sample, which will seriously change the mechanical properties and chemical composition of the prepared product; (2) When preparing oxide ceramics (such as alumina, zirconium oxide, etc.) or many other functional ceramics through hot isostatic pressing, if nitrogen is chosen as the pressure transfer medium, nitrogen can easily enter the crystal in the form of defects or vacancies during the high temperature and high pressure experiment. (3) Nitrogen used in industrial applications often contains trace amounts of water, carbon dioxide and oxygen. If the purification is incomplete or incomplete, the oxidation, denitrification and decarbonization reactions of the sample will be accelerated during the high temperature and high pressure experiment, which will seriously affect the physicochemical properties of the sample product. (4) Although nitrogen has a lower cost advantage compared to argon, for high-value-added hot isostatic pressing workpieces such as aerospace parts and medical implants, the aviation safety cost, health cost and scrap loss cost caused by the nitriding reaction are far greater than the gas pressure transmission medium cost of the hot isostatic pressing experiment itself. Compared with hydrogen, argon can be mixed with oxygen in the air in any proportion, and hydrogen may also cause an explosion hazard under high temperature and high pressure. Compared with other common inert gases such as helium and neon, argon has unique advantages such as good thermal conductivity and lower price.

[0035] This invention uses high-purity argon gas with a purity of 99.999% as the pressure transmission medium. Its main purpose is to: (1) inject argon gas into the cylinder through a high-pressure pipeline and with the help of a booster pump, and then heat it in the cylinder by a high-temperature resistant graphite furnace. The isotropic temperature and pressure will be uniformly transmitted to the albite sample powder pressing parts to complete the hot isostatic pressing molding experiment; (2) Argon gas has excellent thermal conductivity, so the temperature distribution in the furnace is relatively uniform; (3) Selecting high-purity inert gas argon gas isolates other gases in the environment and can completely avoid the steel cladding from being oxidized during the hot isostatic pressing experiment; (4) Selecting high-purity inert gas argon gas plays an important protective role for the core component of the RD80×100‒2000–200 double two thousand type hot isostatic pressing equipment - the graphite heating element, and extends its service life.

[0036] Step 12: In this invention, argon is used as the pressure transmission medium. During the preparation of polycrystalline albite polymers on an RD80×100‒2000–200 double 2000-type hot isostatic pressing (HIP) device, a multi-gradient HIP molding process of first increasing pressure and then increasing temperature is employed. Since the initial material of this invention is a mineral powder that is difficult to mold, using argon as the inert gas pressure transmission medium and selecting a multi-gradient HIP molding process of first increasing pressure and then increasing temperature can greatly improve the density and compactness of large-volume polycrystalline albite polymer products.

[0037] This invention employs a multi-gradient hot isostatic pressing (HIP) process, involving prior pressurization followed by heating, to synthesize large-volume experimental samples of high-density, high-compactness, and high-purity polycrystalline albite polymers. The target pressure and temperature for the HIP experiment are 93.2 MPa and 1050 °C, respectively. If the selected target pressure and temperature are too low, the steel sheath used to seal the albite sample powder during the HIP experiment will not be sufficiently compressed and effectively deformed, making it difficult to fully compact and sinter the sample. This severely affects the preparation of the experimental product—a large-volume, high-density, and high-compact polycrystalline albite polymer sample. Conversely, if the selected target pressure and temperature are too high, the framework-structured plagioclase aluminosilicate mineral—albite—will decompose during the HIP experiment, significantly impacting the prepared polycrystalline albite polymer product.

[0038] This invention uses argon gas as the pressure transmission medium. The target pressure and temperature values ​​are obtained by inputting argon gas into a gas cylinder. Therefore, before the hot isostatic pressing (HIP) experiment of albite sample powder, it is necessary to accurately calculate the amount of argon gas required for the target pressure and temperature values. Through multiple repeatable low-temperature high-pressure empty furnace HIP molding experiments, high-temperature low-pressure empty furnace HIP molding experiments, and high-temperature high-pressure empty furnace HIP molding experiments of albite sample powder, precise temperature and pressure calibration of the albite sample cavity is performed. Finally, based on the RD80×100‒2000–200 double 2000-type HIP equipment, high-purity inert argon gas is selected as the pressure transmission medium to complete the sample preparation for a single large-volume polycrystalline albite polymer HIP experiment. The formula for calculating the amount of argon gas consumed is as follows:

[0039] (1)

[0040] (2)

[0041] In the formula: parameter P target The target pressure for preparing polycrystalline albite polymer samples under hot isostatic pressing (T) is based on the target temperature of the hot isostatic pressing experiment (T). target ) Perform the calculation; parameter P bottleThe pressure inside the cylinder represents the inert gas argon; parameter t represents the number of 40-liter large-volume and high-purity inert gas argon (purity: 99.999%) cylinders required to complete a single hot isostatic pressing experiment on a polycrystalline albite polymer sample under high temperature and high pressure conditions.

[0042] Step 13, vacuuming, filling with argon gas and washing the furnace, the purpose of which is to completely remove the air from the albite sample chamber. The specific operation steps are as follows: (1) Vacuuming: turn on the gas vacuum pump control switch to evacuate the air in the high-pressure sample chamber that is directly connected to the gas vacuum pump. When the detection value of the vacuum degree instrument digital display reaches 10 –4 (1) When the pressure reaches 15 MPa, turn off the gas vacuum pump; (2) Fill the cylinder directly connected to the high-purity inert gas argon with argon gas, and stop filling the pressure medium when the pressure in the sample chamber reaches 15 MPa; (3) Clean the furnace: turn on the gas vacuum pump and pump the vacuum in the sample chamber to 10 MPa. –4 MPa, repeated evacuation and filling three times, thus completely removing all the air from the sample chamber.

[0043] Step 14: Pre-filling and pressurizing the sample chamber. Specific operation steps: (1) Calculate the amount of inert argon gas according to Formula 1 and Formula 2. In order to achieve the target pressure of 93.2 MPa and the target temperature of 1050 °C, at least 4 argon cylinders with an internal pressure of 15 MPa are required; (2) Fill the argon cylinders with an internal pressure of 15 MPa evenly into the high-pressure pressurization tank of the hot isostatic pressing equipment. Then, through the high-pressure delivery pipeline, fill the cylinder with argon gas from the high-pressure pressurization tank, so that the pressure of the high-pressure pressurization tank and the pressure in the cylinder are balanced; (3) Turn on the diaphragm compressor and pump all the remaining argon gas in the high-pressure tank into the sodium feldspar sample chamber of the cylinder, so that the sample chamber of the cylinder is pre-filled and pressurized to 47.5 MPa.

[0044] Step 15: Multi-gradient cylinder block heating and pressurization (see...) Figure 1Taking into account the target pressure and temperature for preparing polycrystalline albite polymer samples in the hot isostatic pressing (HIP) experiment, as well as the safety, reliability, and durability of the graphite heating element itself, a multi-gradient cylinder heating and pressurization HIP experimental procedure was precisely controlled and automatically adjusted. The specific steps are as follows: In the temperature range of room temperature–600 °C, a heating rate of 18.3 °C / min and a pressurization rate of 0.76 MPa / min were used to raise the temperature in the cylinder sample chamber to 600 °C and the pressure to 70.4 MPa; in the medium temperature range of 600 °C–900 °C, a heating rate of 10 °C / min and a pressurization rate of 0.47 MPa / min were used to raise the temperature in the cylinder sample chamber to 900 °C and the pressure to 84.5 MPa; in the high temperature range of 900 °C–1050 °C, a heating rate of 7.5 °C / min and a pressurization rate of 0.47 MPa / min were used. A pressurization rate of MPa / min was used to raise the temperature inside the sample chamber to 1050 °C and the pressure to 93.2 MPa. As the temperature increased, the argon gas inside the sealed cylinder expanded dramatically. Since the cylinder volume remained constant, the argon gas volume was uniformly compressed, resulting in uniform high pressure. Ultimately, the pressure inside the sample chamber was maintained at 93.2 MPa, ensuring that the albite sample, a framework-structured plagioclase aluminosilicate mineral, was fully compacted and cemented. The albite sample powder was held at 93.2 MPa and 1050 °C for 7.9 hours. Albite is the most abundant sodium-rich plagioclase mineral in the Earth's crust and a core raw material in modern industry (ceramics, glass). It is a triclinic mineral with a C1 (or P-1) space group and low symmetry, exhibiting relatively complex crystal morphology, distinct preferred lattice orientations, and anisotropic physicochemical properties.

[0045] This invention employs a multi-gradient hot isostatic pressing (HIP) process, involving first increasing pressure and then increasing temperature, to prepare polycrystalline albite polymer samples. The samples are held at a target pressure of 93.2 MPa and a target temperature of 1050 °C for 7.9 hours to ensure a sufficiently long holding time. If the holding time is too short, it is difficult to form strong bonding forces between the low-symmetry and diverse crystal morphologies of albite mineral particles, and it is also difficult to overcome the influence of many unfavorable factors such as the preferred lattice orientation and anisotropy of the albite minerals, thus affecting the density and strength of the final bulk polycrystalline albite polymer sample. Conversely, if the holding time is too long, although a highly dense and strong polycrystalline albite polymer can be obtained, the final bulk polycrystalline albite polymer sample will experience particle growth, uneven particle distribution, and recrystallization under prolonged high temperature and pressure, severely affecting the preparation effect and resulting in higher experimental costs.

[0046] Step 16: Cooling and depressurizing the cylinder. After the albite sample powder was kept at a constant temperature and pressure of 93.2 MPa and 1050 °C for 7.9 hours, the temperature inside the sample chamber was reduced to 162 °C and the pressure to 50.7 MPa at a relatively slow and uniform cooling rate of 16.44 °C / min and a uniform depressurization rate of 0.79 MPa / min. The relatively slow and uniform cooling and depressurization rate was used primarily because if the cooling and depressurization rate were too fast, the internal stress of the steel sheath would not be fully released, leading to the direct fragmentation and damage of the large-volume polycrystalline albite polymer sample, which would severely affect the preparation results.

[0047] This invention selects a temperature of 162 °C within the sample chamber of the cylinder because this temperature falls within the safe temperature range (160 °C–180 °C) that the RD80×100‒2000–200 dual 2000-type hot isostatic pressing (HIP) equipment can withstand direct pressure relief. If the cylinder temperature within the sample chamber exceeds 180 °C, the resulting excessive internal pressure can easily damage the graphite heating furnace and may also cause a safety accident with the HIP equipment. Conversely, if the temperature within the sample chamber is below 160 °C, the resulting excessive internal pressure makes it difficult to ensure that the argon inert pressure-transmitting medium sealed within the sample chamber is completely expelled during the pressure relief process in the HIP experiment.

[0048] Step 17, Depressurization. First, allow the argon gas in the hot isostatic pressing (HIP) cylinder to flow freely back to the high-pressure pressurization tank through the pipeline. Then, when the cylinder pressure and the high-pressure pressurization tank pressure reach equilibrium, turn on the diaphragm compressor to vent the gas in the cylinder and discharge all residual gas through the pipeline.

[0049] Step 18: Cooling down. After all the inert argon gas in the pipeline has been completely removed, the cooling system connected to the hot isostatic pressing furnace body continues to be turned on, and the natural cooling program is started to reduce the temperature inside the furnace from 162 °C to room temperature (~25 °C).

[0050] Step 19: Set the control program for the hot isostatic pressing (HIP) equipment, open the furnace chamber, carefully remove the polycrystalline albite polymer steel-clad workpiece sealed after the HIP experiment, and accurately measure the dimensions of the steel cladding after the HIP forming experiment: 52.79 mm (outer diameter) × 80.19 mm (height). Compare the volume of the steel cladding before the HIP experiment and calculate the volume shrinkage rate (η) of the steel cladding before and after the HIP experiment. 钢包套 Its calculation formula can be expressed as: η 钢包套 =(V 实验前钢包套 –V 实验后钢包套 ) / V 实验前钢包套 The shrinkage rate (η × 100%) is 18.92%. This invention exhibits such a large volumetric shrinkage rate (η) of the steel sheath. 钢包套=18.92%), confirming that the steel sleeve used to seal and encapsulate the albite sample powder underwent sufficient compression and effective deformation during the hot isostatic pressing experiment.

[0051] Step 20: Using a high-speed diamond saw blade cutter with a 1.0 mm thick diamond blade, the polycrystalline albite polymer sample was carefully peeled from the steel ladle. The weight of the sample after the experiment was accurately measured to be 299 grams, and the tare weight of the steel ladle was 500 grams. This indicates that the weight of the albite sample remained essentially unchanged before and after the multi-gradient hot isostatic pressing (HIP) experiment, which involved increasing pressure followed by increasing temperature. Further precise measurements were taken of the dimensions of the polycrystalline albite polymer sample obtained after the HIP experiment: 46.79 mm (diameter) × 70.19 mm (height). Comparing the volume of the initial albite powder sample encapsulated in the steel ladle before the HIP experiment, the volume shrinkage rate (η) of the sample before and after the HIP experiment was calculated. 钠长石 Its calculation formula can be expressed as: η 钠长石 =(V 实验前钠长石 –V 实验后钠长石 ) / V 实验前钠长石 The volume shrinkage rate (η × 100%) is 21.06%. This invention exhibits such a large volume shrinkage rate (η × 100%) in the albite sample powder. 钠长石 =21.06%), confirming that during the hot isostatic pressing experiment, the sodium feldspar sample powder placed in the steel cladding was fully compacted and sintered under high temperature and high pressure conditions.

[0052] This invention utilizes an RD80×100‒2000–200 dual 2000-type hot isostatic pressing (HIP) apparatus. The process involves synthesizing a polycrystalline albite polymer from the initial material—a single-phase albite single crystal—through crushing into medium-sized albite single crystal particles, grinding into fine-grained albite powder, and finally producing the final product. Employing a multi-gradient HIP process that first increases pressure and then increases temperature, high-density, high-compactness, high-purity, and bulk polycrystalline albite polymers are prepared. No other impurity phases are introduced during the entire preparation process, and the purity of the resulting polycrystalline albite polymer samples can reach 100%.

[0053] Under epoxy resin inlay protection, a representative sample (21 mm × 21 mm cross-section) was cut from the polycrystalline albite polymer workpiece, a product of the hot isostatic pressing experiment. The sample underwent epoxy resin inlay protection, cutting, grinding, and surface polishing. Using a high-precision Olympus SZX16 research-grade stereomicroscopic imaging platform, the surface morphology and particle size distribution characteristics of the polycrystalline albite polymer sample were tested. The test results are shown in (see...). Figure 3The polycrystalline albite aggregate exhibits clear grain boundary continuity, with minimal differences in the proportion of particles of different sizes, demonstrating a distinctly uniform particle size distribution. This invention utilizes a fully sealed steel sheath and inert argon gas pressure transmission medium throughout the hot isostatic pressing (HIP) experiment, ensuring the sample powder remains in a closed vacuum environment. This effectively isolates the sample from gases such as nitrogen, oxygen, and water vapor, thus achieving uniform particle distribution, no particle growth, and no recrystallization in the polycrystalline albite aggregate. Compared to existing technologies that use quasi-hydrostatic presses such as the YJ-3000t and Kawai-1000t to synthesize island-shaped silicate mineral single crystals under high temperature and high pressure, this invention employs a multi-gradient HIP molding process that first increases pressure and then increases temperature, effectively overcoming numerous drawbacks of polycrystalline albite aggregate products, such as particle growth, uneven particle distribution, and recrystallization.

[0054] High-resolution scanning electron microscopy was used to observe the microstructure of the polycrystalline albite polymer sample obtained from the hot isostatic pressing experiment, and precise density tests were performed. The obtained polycrystalline albite polymer had a density as high as 99.8%, exhibiting extremely high compactness. In the hot isostatic pressing (HIP) experiment, the present invention improves the following specific experimental scheme to ensure the acquisition of highly dense polycrystalline albite polymer samples: (1) a higher pre-charge pressure (47.5 MPa); (2) a multi-gradient gradually decreasing cylinder heating mode, namely, in the low-temperature zone of the HIP experiment: room temperature–600 °C, the heating rate is 18.3 °C / min; in the medium-temperature zone: 600 °C–900 °C, the heating rate is 10 °C / min; in the high-temperature zone: 900 °C–1050 °C, the heating rate is 7.5 °C / min; (3) a multi-gradient gradually decreasing cylinder pressure mode, namely, in the low-pressure zone of the HIP experiment: 47.5 MPa–70.4 MPa, the pressure rate is 0.76 MPa / min; in the medium-pressure zone: 70.4 MPa–84.5 MPa… Under pressure conditions of MPa, the pressurization rate is 0.47 MPa / min and under pressure conditions of 84.5 MPa–93.2 MPa, the pressurization rate is 0.44 MPa / min; (4) The relatively slow cylinder uniform cooling and depressurization mode, under pressure conditions of 93.2 MPa–50.7 MPa, the uniform cooling rate and depressurization rate are 16.44 °C / min and 0.79 MPa / min, respectively; (5) The long-term constant temperature and constant pressure mode, at the highest temperature (1050 °C) and the highest pressure (93.2 MPa), ensures a sufficiently long constant temperature and constant pressure of 7.9 hours. All these optimized and improved hot isostatic pressing (HIP) experimental schemes can promote sufficient diffusion and particle aggregation between albite sample powders during HIP, eliminate the adverse effects of dendritic formation between sample powders, and thus form a uniform equiaxed grain structure; they can also promote the uniform isotropic temperature and pressure transmission during HIP, prevent the occurrence of local weaknesses or cracks, and thus greatly improve the compactness of the polycrystalline albite polymer sample produced by HIP. In addition, this invention applies a higher temperature (1050 °C), a higher pressure (93.2 MPa), and a sufficiently long heat and pressure holding time (7.9 hours) to promote the formation of good bonding force between the particles of albite sample powder, thereby greatly improving the density and strength of the polycrystalline albite aggregate sample produced by hot isostatic pressing. It also effectively overcomes the unavoidable temperature gradient, pressure gradient, and many adverse factors such as pores, voids, cracks, and healing defects in the experimental products produced by the existing technology that uses quasi-hydrostatic presses such as YJ-3000t and Kawai-1000t to synthesize island silicate mineral single crystals.

[0055] The Archimedes method using organically combined secondary deionized water and the water intrusion method for porous and complex structures were employed to accurately measure the density of polycrystalline albite polymer samples obtained from hot isostatic pressing experiments. The measured density of the polycrystalline albite polymer was 2.64 g / cm³. 3 This density value falls exactly within the theoretical density of 2.61 g / cm³ for naturally collected albite, as measured by geologists. 3 -2.65 g / cm 3 Within the specified range, the obtained bulk polycrystalline albite polymer samples exhibited extremely high density. The high density of these polycrystalline albite polymer products is highly correlated with the optimized molding process employed during this hot isostatic pressing experiment, including pretreatment of the albite sample powder raw material, selection of a No. 20 steel sample cladding, a reasonable cooling and depressurization hot isostatic pressing molding process, and high-temperature degassing at 400 °C. The pretreatment of albite sample powder raw materials, namely fine-grained albite mineral powder with a particle size of 13.75 μm to 21.84 μm, is crucial. Albite within this particle size range has a large specific surface area, significantly increasing the contact area between sample particles. This promotes stronger bonding and greatly enhances the density of the prepared polycrystalline albite polymer sample. A 3 mm thick 20# low-carbon steel continuous casting slab serves as the steel cladding, possessing excellent physical properties such as low strength, low hardness, high plasticity, and good toughness. This allows the high pressure borne by the steel cladding to be uniformly transferred to the albite sample powder enclosed within, further increasing the density of the prepared polycrystalline albite polymer sample. An optimized and improved cooling and depressurization hot isostatic pressing process is employed, particularly using a slower and more uniform cylinder depressurization mode (pressurization rate: 0.44 MPa / min – 0.76 MPa / min; depressurization rate: 0.79 MPa / min). (MPa / min) ensures that the internal stress of large-volume polycrystalline albite polymer workpieces is fully released, effectively overcoming the adverse effects of delamination, cracks, and fissures in the sample product, and greatly improving the density of the polycrystalline albite polymer sample. A high-temperature degassing optimization molding process at 400 °C is employed, sealing the albite sample powder in a steel sleeve and subjecting it to high-temperature vacuum degassing at 400 °C to minimize residual gas, thereby obtaining polycrystalline albite polymer experimental samples with a very uniform density distribution under hot isostatic pressing. In contrast, existing technologies, such as the synthesis of island silicate mineral single crystals using quasi-hydrostatic presses like the YJ-3000t and Kawai-1000t, inevitably generate internal friction due to the unidirectional pressing, leading to uneven density distribution and delamination problems in the experimental product.

Claims

1. A method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions, characterized in that: The method includes: completely sealing the albite sample powder in a vacuum of 10... –3 The steel cladding was placed inside the graphite furnace cylinder of the high-pressure vessel of a hot isostatic pressing (HIP) apparatus, and a graphite sealing cap was placed on top. Argon gas was used as the pressure transmission medium. The temperature inside the sample chamber of the cylinder was raised to 1050 °C and the pressure was raised to 93.2 MPa using a multi-gradient cylinder heating and pressurization method, and the temperature and pressure were maintained for 7.9 hours. The temperature inside the sample chamber of the cylinder was lowered to 162 °C and the pressure was reduced to 50.7 MPa at a cooling rate of 16.44 °C / min and a depressurization rate of 0.79 MPa / min. Finally, the pressure was released and the temperature was cooled to room temperature to obtain polycrystalline albite polymer.

2. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: The preparation process of the albite sample powder includes: Step 1: Select albite single crystal mineral particles with a minimum particle size of 5.4 mm and a maximum particle size of 11.3 mm as the initial sample; Step 2: Place the selected albite single crystal mineral particles on an ultrasonic cleaner, and use acetone, alcohol and deionized water as cleaning solutions in sequence for ultrasonic cleaning for 19 minutes. Step 3: Select 300 grams of albite single crystal particles that are complete in crystal form, uniform in color and colorless and transparent, fresh in surface and free of impurities. Step 4: Place the selected albite single crystal particles in a vacuum drying oven at 200 degrees Celsius and dry for at least 20 hours. Step 5: Crush the albite single crystal particles into mineral single crystal particles with a particle size of less than 2 mm; Step 6: Grind the mineral single crystal particles into albite mineral powder with a particle size of 13.75 micrometers to 21.84 micrometers; Step 7: Pack the albite mineral powder into a paper sealed bag and dry it in a vacuum drying oven at 90 degrees Celsius for 23 days to obtain albite sample powder.

3. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: The methods for preparing steel sheaths include: Step 8: Select a continuous casting slab of No. 20 low carbon steel with a wall thickness of 3 mm, heat it to 200 °C, and then use the roughing mill and finishing mill to cool it to the set temperature through laminar flow. The slab is then rolled into a steel strip coil by a coiler, and then undergoes three rolling processes and multiple hot rolling processes including edge trimming to finally obtain a steel cladding sleeve with dimensions of 57.02 mm (outer diameter) × 84.78 mm (height) × 3 mm (wall thickness). A continuous casting slab of No. 20 low-carbon steel with a wall thickness of 3 mm was selected. The same hot rolling process was used to prepare the upper and lower sealing caps of the steel cladding. The cladding, upper and lower sealing caps were welded together by high-temperature vacuum welding to prepare a complete steel cladding.

4. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: The albite sample powder was completely sealed in a vacuum of 10. –3 The method in the steel cladding of Pa includes: Step 9, firstly, vacuum welding the sleeve and lower sealing cap of the steel cladding, then placing the albite sample powder inside the steel cladding, and after compaction, vacuuming, high-temperature degassing, and high-temperature vacuum welding, completely sealing the albite sample powder in a vacuum of 10... –3 In the steel bladder of Pa; vacuuming is required for at least 67 hours, followed by high-temperature degassing at 400 °C.

5. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: The purity of the pressure-transmitting medium, argon, is 99.999%; the formula for calculating the amount of argon gas consumed is: (1)； (2)； In the formula: parameter P target The target pressure for preparing polycrystalline albite polymer samples under hot isostatic pressing (T) is based on the target temperature of the hot isostatic pressing experiment (T). target ) Perform the calculation; parameter P bottle The pressure inside the cylinder represents the inert gas argon; parameter t represents the number of 40-liter cylinders with 99.999% argon purity required to complete a single hot isostatic pressing experiment on a polycrystalline albite polymer sample under high temperature and high pressure conditions.

6. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: Argon gas filling methods include: Step 13, Vacuuming: Turn on the gas vacuum pump control switch to evacuate the air sealed in the high-pressure sample chamber, which is directly connected to the gas vacuum pump. Evacuate until the vacuum level instrument's digital display reaches 10... –4 At MPa, turn off the gas vacuum pump; Fill the cylinder directly connected to argon gas with argon gas, and stop filling when the pressure in the sample chamber reaches 15 MPa; Clean the furnace: Turn on the gas vacuum pump and evacuate the vacuum in the sample chamber to 10 MPa. –4 MPa, repeat the evacuation and filling three times to completely remove all the air from the sample chamber; Step 14: Calculate the amount of argon gas. At least four argon cylinders with an internal pressure of 15 MPa are required. Fill the argon cylinders with an internal pressure of 15 MPa evenly into the high-pressure tank of the hot isostatic pressing equipment. Then, through the high-pressure delivery pipeline, freely fill the cylinder with the argon gas from the high-pressure tank to achieve a balance between the pressure in the high-pressure tank and the pressure in the cylinder. Turn on the diaphragm compressor to pump all the remaining argon gas in the high-pressure tank into the albite sample chamber of the cylinder, so that the sample chamber of the cylinder is pre-pressurized to 47.5 MPa.

7. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: The method of raising the temperature to 1050 °C and the pressure to 93.2 MPa within the cylinder sample chamber using a multi-gradient cylinder heating and pressurization approach includes: raising the temperature to 600 °C and the pressure to 70.4 MPa within the temperature range of room temperature to 600 °C using a heating rate of 18.3 °C / min and a pressurization rate of 0.76 MPa / min; raising the temperature to 900 °C and the pressure to 84.5 MPa within the temperature range of 600 °C to 900 °C using a heating rate of 10 °C / min and a pressurization rate of 0.47 MPa / min within the temperature range of 900 °C to 1050 °C using a heating rate of 7.5 °C / min and a pressurization rate of 0.44 MPa / min within the temperature range of 900 °C to 1050 °C using a pressurization rate of 0.44 MPa / min within the temperature range of 900 °C to 1050 °C using a pressurization rate of 0.44 MPa / min within the temperature range of 1050 °C to 93.2 MPa.

8. The method for preparing high-density bulk polycrystalline albite polymer under high temperature and high pressure conditions according to claim 1, characterized in that: Methods for obtaining polycrystalline albite polymers by depressurization and cooling to room temperature include: Step 17, Depressurization: First, let the argon gas in the cylinder of the hot isostatic press flow freely back to the high-pressure pressurization tank through the pipeline; when the cylinder pressure and the high-pressure pressurization tank pressure reach equilibrium, turn on the diaphragm compressor to release the gas in the cylinder and discharge all the residual gas through the pipeline. Step 18, Cooling: After all the inert argon gas in the pipeline has been completely removed, the cooling system connected to the furnace body of the hot isostatic pressing equipment continues to be turned on, and the natural cooling program is started to reduce the temperature inside the furnace from 162 °C to room temperature. Step 19: Set the control program for the hot isostatic pressing equipment, open the furnace, and remove the steel ladle sleeve sealed after the hot isostatic pressing test. Step 20: Remove the polycrystalline albite polymer sample from the ladle.

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