阅读说明：本技术 基于金云母籽晶制备翡翠微晶玻璃的方法 (Method for preparing emerald glass ceramics based on phlogopite seed crystals ) 是由 郭志超 刘大平 王金龙 刘岩 于 2021-01-21 设计创作，主要内容包括：本发明公开了一种云母籽晶制备翡翠微晶玻璃的方法,属于材料合成技术领域。本发明的技术方案要点为：以硅酸铝、硅酸钠、金云母为原料,按翡翠(NaAlSi-2O-6)的分子式中各元素的理论质量分数配比进行配料,通过对前驱料处理,在高温常压下制备玻璃料,再经过对玻璃料粉碎后,混入金云母做籽晶在高温炉中烧结制备样品。采用云母籽晶诱导高温常压制备翡翠开发出一种新的人工制备翡翠微晶玻璃工艺；籽晶诱导促使NaAlSi-2O-6晶化形成片状晶体,降低了制备条件和成本。(The invention discloses a method for preparing emerald glass ceramics by mica seed crystals, belonging to the technical field of material synthesis. The technical scheme provided by the invention has the key points that: prepared from aluminium silicate, sodium silicate and phlogopite as raw materials by mixing with jade (NaAlSi) 2 O 6 ) The theoretical mass fraction ratio of each element in the molecular formula (1) is proportioned, the precursor is treated to prepare glass frit under high temperature and normal pressure, and the glass frit is crushed and then mixed with phlogopite as seed crystal to be sintered in a high temperature furnace to prepare a sample. Mica seed crystal is adopted to induce high temperature and normal pressure to prepare jade, and a new process for artificially preparing jade microcrystalline glass is developed; seed crystal induction promoting NaAlSi 2 O 6 Crystallization forms plate-like crystals, reducing the productionPreparation conditions and cost.)

1. The method for preparing the emerald glass ceramics based on the phlogopite seed crystals is characterized by comprising the following specific steps:

step S1: preparation of precursor

Takes aluminum silicate and sodium silicate as raw materials and takes jade NaAlSi as raw material₂O₆The theoretical molar ratio of each element in the molecular formula is respectively weighed, firstly, the aluminum silicate and the sodium silicate are sampled according to the equimolar amount, the chromium oxide chromogen with the physical mass of 1 percent is added, then, the three are ball-milled, crushed and mixed, and the mixture is placed in a muffle furnace to be kept at 150 ℃ for 2 hours and then taken outCrushing, grinding and briquetting the lump materials to finish the preparation of the precursor material;

step S2: preparation of emerald glass frit

Putting the pressed precursor material into a high-temperature furnace for sintering treatment, wherein the sintering conditions are as follows: the heating rate is 5 ℃/min, the temperature is kept at 1200 ℃ for 300min, then the sample is cooled to normal temperature, and the sample is taken out after the cooling;

step S3: preparation of microcrystalline glass by crystallization of phlogopite-induced emerald glass material

Grinding the jade glass material obtained by sintering, mixing with 5% of phlogopite by mass of a sample, pressing into a block, and sintering in a high-temperature furnace, wherein the sintering conditions are as follows: the temperature rise rate is 5 ℃/min, the temperature is kept at 1000 ℃ for 300min and then is reduced, when the temperature is reduced to be lower than 980 ℃, the temperature is slowly reduced to 920 ℃ at the rate of 0.2 ℃/h, finally, the sample is cooled to the room temperature along with the furnace, the seed crystal guiding infiltration growth process is completed, and finally, the preparation of the jade microcrystalline glass is completed.

Technical Field

The invention belongs to the technical field of material synthesis, and particularly relates to a method for preparing emerald glass ceramics based on phlogopite seed crystals.

Background

The microcrystalline glass is base glass with specific composition, and is subjected to crystallization heat treatment at a certain temperature, a large number of micro crystals are uniformly precipitated in the glass to form a compact multiphase complex of a microcrystalline phase and a glass phase, and the microcrystalline glass has the dual characteristics of glass and ceramic, and is high in strength and good in mechanical strength; the dielectric ceramic has excellent electrical properties, low dielectric loss rate and excellent electrical insulation; the material has good thermal property, low thermal expansion coefficient, good thermal vibration stability and high deformation temperature; the water-resistant and hydration-resistant agent has more stable chemical performance, water resistance, hydration resistance and cation exchange resistance; good processing performance, can be matched with a plurality of materials, and the like. It has been widely used in many fields. The glass ceramics are classified according to the composition of the base glass, and are mainly classified into silicates [ CaMgSi ]₂O₆And CaSiO₃]And aluminosilicate [ LiO ]₂-Al₂O₃-SiO₂System, Al₂O₃-MgO-SiO₂System, Na₂O-Al₂O₃-SiO₂Series, ZnO-Al₂O₃-SiO₂Is a system]Phosphates and fluorosilicates [ KMg₃AlSi₃O₁₀F₂]With the advancement of science and technology and the increasing demand of people on functional materials, the microcrystalline glass materials with more complex components, finer structure and more excellent performance are required.

The microcrystalline glass is Na₂O-Al₂O₃-SiO₂Is one of microcrystalline glasses, Na₂O-Al₂O₃-SiO₂The microcrystalline phase of the glass matrix is jadeite microcrystalline (NaAl (SiO)₃)₂). The main problem of preparing the jade microcrystalline glass is the heat treatment process, and the crystallization of the glass matrix to form the jade microcrystalline is difficult. It has not been commercially produced. At present, the preparation method is an improvement of three methods (melting method, sintering method and sol-gel method) for preparing the traditional microcrystalline glass. 1) Solid phase sintering method modified by sintering method and melting method, one is to synthesize jadeite (NaAlSi) first₂O₆) And then converted into a crystalline jadeite aggregate in a high temperature and high pressure apparatus. Secondly, is atThe high-temperature high-pressure device is simultaneously added with oxide with a proportion corresponding to that of jadeite as a raw material for synthesizing jadeite and a proper amount of coloring ions as a coloring agent, and then the artificial synthesis is obtained through one-step high-temperature high-pressure sintering. 2) The improved sol-gel process has the preparation process including mixing the materials homogeneously in liquid phase and reaction to form wet sol system. And drying and grinding the wet gel to obtain powder, and calcining and quenching the powder to obtain the glass material with the jade component. And then the high-temperature high-pressure treatment is carried out on the product in a cubic press. 3) A powder reconstruction method comprises the steps of utilizing leftover materials of natural jade and low-grade jade with more impurities as raw materials, crushing the raw materials, separating weak magnetic amphibole and iron-containing minerals in the jade by a magnetic separation method, adding natural chromium-rich jadeite as a coloring agent and lead-free borate glass as a binder, and performing Spark Plasma Sintering (SPS) by students to obtain powder reconstruction. The commercial value of using high temperature and high pressure equipment to prepare emerald glass ceramics is lower, and the size of prepared samples is also influenced by the limitation of the high temperature and high pressure equipment. Therefore, the method for researching and developing the low-cost preparation of the jade microcrystalline glass has important practical value and scientific research significance.

Disclosure of Invention

The invention provides a method for preparing emerald glass ceramics based on phlogopite seed crystals, which aims to solve the core problem of preparing emerald glass ceramics, realize the conversion from emerald glass to jadeite mineral crystals, develop a low-cost process for artificially synthesizing emerald glass ceramics and realize the preparation of the emerald glass ceramics.

The invention adopts the following technical scheme for solving the technical problems, and the method for preparing the emerald glass ceramics based on the phlogopite seed crystals is characterized by comprising the following specific steps:

step S1: preparation of precursor

Takes aluminum silicate and sodium silicate as raw materials and takes jade NaAlSi as raw material₂O₆The theoretical molar ratio of each element in the molecular formula is respectively weighed, firstly, the aluminum silicate and the sodium silicate are sampled according to the equimolar amount, the chromium oxide chromogen with the physical mass of 1 percent is added, then, the three are ball-milled, crushed and mixed, the mixture is placed in a muffle furnace to be kept at 150 ℃ for 2 hours and then taken out, and the lump materials are put into a muffle furnaceCrushing, grinding and briquetting to finish the preparation of precursor;

step S2: preparation of emerald glass frit

Putting the pressed precursor material into a high-temperature furnace for sintering treatment, wherein the sintering conditions are as follows: the heating rate is 5 ℃/min, the temperature is kept at 1200 ℃ for 300min, then the sample is cooled to normal temperature, and the sample is taken out after the cooling;

step S3: preparation of microcrystalline glass by crystallization of phlogopite-induced emerald glass material

Grinding the jade glass material obtained by sintering, mixing with 5% of phlogopite by mass of a sample, pressing into a block, and sintering in a high-temperature furnace, wherein the sintering conditions are as follows: the temperature rise rate is 5 ℃/min, the temperature is kept at 1000 ℃ for 300min and then is reduced, when the temperature is reduced to be lower than 980 ℃, the temperature is slowly reduced to 920 ℃ at the rate of 0.2 ℃/h, finally, the sample is cooled to the room temperature along with the furnace, the seed crystal guiding infiltration growth process is completed, and finally, the preparation of the jade microcrystalline glass is completed.

Compared with the prior art, the invention has the following beneficial effects: the invention provides a conversion process for realizing the conversion from jade glass to crystal under normal pressure by adopting a method for promoting the crystallization of jade glass by seed crystal induction; the seed crystal induction preparation under normal pressure solves the problem that the traditional jadeite crystallization condition is realized at high temperature and high pressure, reduces the preparation equipment condition and cost, and the sample volume is not limited by a sintering furnace.

Drawings

FIG. 1 is an optical photograph of a sample prepared according to an embodiment of the present invention;

FIG. 2 is an optical photograph taken at 40 times under a microscope of a sample prepared according to an embodiment of the present invention;

FIG. 3 is an XRD spectrum of a sample prepared according to an embodiment of the present invention;

FIG. 4 is an SEM image of a sample prepared according to an embodiment of the present invention;

FIG. 5 is a TEM image of a sample prepared according to an example of the present invention (a) a wide-area image and (b) a local-area image.

Detailed Description

The present invention is described in further detail below with reference to examples, but it should not be construed that the scope of the above subject matter of the present invention is limited to the following examples, and that all the technologies realized based on the above subject matter of the present invention belong to the scope of the present invention.

Examples

Using aluminium silicate and sodium silicate as raw materials, according to the formula of jadeite (NaAlSi)₂O₆) The method comprises the following steps of weighing theoretical molar ratio proportions of elements in the molecular formula, synthesizing jadeite glass material by high-temperature normal-pressure solid-phase sintering, mixing phlogopite serving as seed crystal into a glass body, and solidifying and crystallizing a sample under the induction of the seed crystal by adopting the following technology and specific steps:

(1) preparation of precursor

Firstly, sampling aluminum silicate and sodium silicate according to equimolar amount, adding chromium oxide chromogen which generates 1% of physical theory mass, then carrying out ball milling crushing and mixing on the aluminum silicate and the sodium silicate, then placing the mixture in a muffle furnace, preserving heat for 2 hours at 150 ℃, taking out the mixture, crushing, grinding and briquetting lump materials to finish the preparation of precursor materials;

(2) preparation of emerald glass frit

Putting the pressed precursor material into a high-temperature furnace for sintering treatment, wherein the sintering conditions are as follows: the heating rate is 5 ℃/min, the temperature is kept at 1200 ℃ for 300min, then the sample is cooled to normal temperature, and the sample is taken out after the cooling;

(3) preparation of microcrystalline glass by crystallization of phlogopite-induced emerald glass material

Grinding the jade glass material obtained by sintering, mixing with 5% of phlogopite by mass of a sample, pressing into a block, and sintering in a high-temperature furnace, wherein the sintering conditions are as follows: the temperature rise rate is 5 ℃/min, the temperature is kept at 1000 ℃ for 300min and then is reduced, when the temperature is reduced to be lower than 980 ℃, the temperature is slowly reduced to 920 ℃ at the rate of 0.2 ℃/h, and finally, the sample is cooled to the room temperature along with the furnace, the seed crystal guided infiltration growth process is completed, and the preparation is completed.

For the test of the prepared sample, fig. 1 is an optical photograph of the sample prepared by the embodiment of the invention, and it can be seen that the sample is uniform and semitransparent as a whole, has glass luster and light green color (the color may be caused by the impurities of Fe, Cr, Pb, etc. in the raw materials). FIG. 2 is an optical photograph of the prepared sample at 40 times microscope, from which the sheet-like structure is formed. FIG. 3 is a sample prepared according to an embodiment of the present inventionXRD spectrum, the XRD of the prepared sample can show that the sample has less amorphous state, and the sintered product is compared with the standard NaAlSi₂O₆The diffraction peak of (A) was found to be NaAlSi₂O₆The crystalline diffraction peak contains impurities such as alumina, but the diffraction peak of the sintered sample is shifted to some extent, which shows that the crystal lattice of the prepared sample has certain difference with the crystal lattice of the standard sample under the condition of no pressure. FIG. 4 is an SEM image of a prepared sample of an embodiment of the present invention, and it can be seen from the microscopic view of FIG. 4 that the prepared sample forms a sheet-like structure. FIG. 5 is a TEM image of a sample prepared by an example of the present invention, wherein the sample is observed in a lamellar manner from (a) a wide area diagram, and the sample is observed in a distinct crystallization from (b) a local area diagram. The comprehensive analysis result shows that the mica is used as the seed crystal to induce the crystallization of the emerald glass, the induced sample has obvious layered structure and crystallization, and the XRD spectrum and the local TEM show that the sample has serious crystallization, less glass and possibly more mica, but the proportion of the glass and the crystal grains in the sample can be adjusted by adding the mica content, thereby being beneficial to adjusting and controlling the performance of the emerald glass ceramics. Other physical properties of the prepared sample were measured to find that the refractive index was about 1.63 and the density was 2.96g/cm³And a mohs hardness of about 5.28.

While there have been shown and described what are at present considered the fundamental principles of the invention, its essential features and advantages, the invention further resides in various changes and modifications which fall within the scope of the invention as claimed.