CN108314296A - A kind of preparation method of laser heating levitation device refractory oxides glass batch - Google Patents

Abstract

The invention provides a method for preparing a refractory oxide glass batch material for a laser heating suspension device, which belongs to the technical field of material preparation. The method uses liquid medium to fully mix the batch materials, and then heat-treats the liquid medium to completely volatilize, which not only solves the problem of introducing impurities, but also can be applied to evenly mix a small amount of various powders, and the process is simple, the mixing degree is high, and the error is small. , to provide a reliable guarantee for the subsequent preparation of glass samples and their performance research, and it is a practical method for the preparation of refractory oxide glass batch materials for laser heating suspension devices.

Description

Preparation method of refractory oxide glass batch material for laser heating suspension device

technical field

The invention relates to a method for preparing a refractory oxide glass batch material for a laser heating suspension device, and belongs to the technical field of material preparation.

Background technique

The laser heating suspension device uses the buoyancy of the airflow to offset the gravity of the object, so that the glass raw material is in a container-free state, which avoids the contact and pollution of the crucible to the material surface, and inhibits heterogeneous nucleation. By irradiating the glass raw material block with laser light to heat and melt it, and turning off the laser light source to quench the molten glass, a great degree of supercooling can be obtained, which is beneficial to the formation of glass, especially the formation of refractory oxide glass.

The size of the glass sample prepared by the suspension method is only a dozen milligrams, so the requirements for the uniformity of the batch materials are extremely strict. The chemical composition of the mixed parts of the batch materials must be close enough to the design composition. If the batch materials cannot be fully mixed and uniform , the impact on performance can be described as a thousand miles away.

The existing preparation methods of refractory oxide glass batch materials for laser heating suspension devices can be divided into two categories: one is the sol-gel method, in which the precursor is formed into a homogeneous solution in a certain solvent, and the solute is hydrolyzed (or Alcoholysis) to form a sol, and then through the process of solvent volatilization or heating to convert the sol into a gel, after drying, grinding and other steps to obtain a mixed powder, and then further molding and sintering to obtain a sheet-like batch material. Although the sol-gel method can achieve molecular-level mixing, it is difficult to completely remove the water molecules in the gel even at high temperatures, resulting in residual hydroxyl groups in the sample, and some of the residual hydroxyl groups have a negative impact on the physical properties of the glass. greater impact.

The other is the mechanical ball milling method, also known as the solid phase method. In this method, the oxide powder is wet ball milled, dried and ground into powder, and then formed and sintered to obtain a flake batch. The ball milling method is a widely used technology at present. The environmental protection effect is strong and the process is relatively simple. However, the error of this method is relatively large. Due to reasons such as different raw material densities, there are often uneven dispersion of the mixture caused by stratification, and the matching that meets the requirements cannot be obtained. In addition, due to the small amount of glass batch materials required for the laser heating suspension device, if the mechanical ball milling method does not have a ball mill jar and ball stones of suitable specifications, it will often get twice the result with half the effort.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for preparing refractory oxide glass batch materials for laser heating levitation devices in view of the above-mentioned deficiencies in the prior art. The method uses liquid medium to fully mix the batch materials, and then heat-treats the liquid medium to completely volatilize, which not only solves the problem of introducing impurities, but also can be applied to evenly mix a small amount of various powders, and the process is simple, the mixing degree is high, and the error is small. , to provide a reliable guarantee for the subsequent preparation of glass samples and their performance research, and it is a practical method for the preparation of refractory oxide glass batch materials for laser heating suspension devices.

The technical scheme that the present invention adopts for solving the above-mentioned problem is:

A method for preparing a refractory oxide glass batch material for a laser heating suspension device, the main steps are as follows:

a. Weighing: Accurately weigh the refractory oxide powder to be mixed, and perform the first grinding and sieving to obtain the mixed powder for later use;

b. Solid-liquid mixing: add a liquid dispersion medium to the mixed powder weighed in step a, and place the resulting mixture on a magnetic stirrer to stir evenly; wherein, the viscosity of the liquid dispersion medium is between 1 and 15 mPa·s at room temperature Between, containing only carbon, hydrogen and oxygen elements, the molecular weight is greater than 90 and can be completely volatilized under high temperature conditions;

c. drying: put the mixture obtained in step b into a heat treatment furnace for drying, so that the dispersion medium is completely volatilized; wherein, the drying temperature is preferably higher than the boiling point of the liquid dispersion medium;

d. Grinding: Grinding the powder obtained in step d for the second time to obtain a more uniform glass batch;

e. Tablet pre-sintering: the glass batch obtained in step e is placed in a mold, pressed into tablets by a tablet press, and the obtained flake glass batch is pre-sintered in a heat treatment furnace to obtain a flake glass batch.

According to the above scheme, the sieving requirement in step a is to pass through a 10,000-mesh sieve, and the particle size of the mixed powder is not greater than 1.5 μm.

According to the above scheme, the liquid dispersion medium in step b can be such as glycerin, polyethylene glycol, etc., and the amount added is preferably to completely cover the mixed powder.

According to the above scheme, in step c, the drying temperature is preferably between 500° C. and 600° C., and the drying time is 3 to 5 hours.

According to the above scheme, the pressure setting of the tablet press described in step e is not less than 10Mpa.

According to the above scheme, the pre-sintering process conditions in step e are as follows: it is advisable to raise the temperature from room temperature at a rate of 5-20°C/min to a temperature not higher than the melting point of each oxide, then keep it warm for 1-6 hours, and finally cool with the furnace to room temperature.

According to the above scheme, the method of the present invention is mainly applicable to glass systems with a melting point higher than 1600° C. such as aluminate and gallate.

Compared with prior art, the beneficial effect of the present invention is:

The invention provides a preparation method of a refractory oxide glass batch material for a laser heating suspension device to solve the problems of uneven mixing, possible introduction of foreign impurities and inappropriate mixing of a small amount of powder in the preparation process of the batch material in the prior art. The invention uses liquid medium to fully mix the batch materials, and then heat-treats the liquid medium to completely volatilize, which not only solves the problem of introducing impurities, but also can be applied to evenly mix a small amount of various powders, and the process is simple, the mixing degree is high, and the error is small , to provide a reliable guarantee for the subsequent preparation of glass samples and their performance research, and it is a practical method for the preparation of refractory oxide glass batch materials for laser heating suspension devices.

The medium used in the invention is easy to prepare, low in cost, completely volatilizes at high temperature, does not have residual hydroxyl groups and carbon elements, does not introduce any impurities into the batch material, and the mixing degree fully meets the requirements.

In addition, the present invention has extremely high flexibility, and can uniformly mix a small amount of various powders, and is not limited by the types of oxides introduced. Using this method to mix the refractory oxide glass batch material for laser heating suspension devices, Often play the effect of getting twice the result with half the effort.

Detailed ways

The specific implementation method of the present invention will be further described below in conjunction with specific examples. It should be stated that the following examples are only used to further verify and describe the technical solutions of the present invention in detail, and should not be construed as limiting the applicable protection scope of the present invention. Non-essential improvements and adjustments made by those skilled in the art according to the claims of the present invention all belong to the protection scope of the present invention.

Example 1

A preparation method of refractory oxide glass batch material for laser heating suspension device, taking SrO-Al ₂ O ₃ binary system as an example, the specific steps are as follows:

1) Using SrO and Al ₂ O ₃ powders as raw materials, weigh a total of 2g of mixed powder according to the formula that the molar fraction ratio of SrO and Al ₂ O ₃ is 55:45;

2) Grind the mixed powder obtained in step 1) for the first time, pass the powder through a 10,000-mesh sieve, and then add polyethylene glycol liquid dispersion medium to the sieved powder, and the addition amount is appropriate to completely cover the powder;

3) Place the solid-liquid mixture obtained in step 2) on a magnetic stirrer and stir for 3 hours;

4) Put the mixture obtained in step 3) into a heat treatment furnace at 550°C for 3 hours to keep the dispersion medium completely volatilized, and then grind for the second time to obtain a more uniform glass batch;

5) Put the glass batch material obtained in step 4) into the mold, and press it with a desktop electronic tablet press at a pressure of 20 MPa;

6) Pre-fire the flake glass batch obtained in step 5) in a heat treatment furnace at 1050°C for 1 hour, and then cool with the furnace to obtain a uniform flake glass batch.

In this embodiment, three points are arbitrarily taken on the SrO- _Al2O3 system flake sample, and it is quantitatively analyzed by an atomic emission spectrometer. After calculation and comparison, the error between the result obtained by the method of the _present invention and the design composition is less than 0.3%, which can be To meet the uniformity requirements of the refractory oxide glass batch used in the laser heating levitation device, the mixing method in this embodiment is feasible.

The traditional sol-gel method is to dissolve aluminum sec-butoxide and strontium nitrate in aqueous citric acid solution, add ethylene glycol and polyethylene glycol as surfactants, control the temperature and continuously stir until the formation of strontium aluminum salt sol, and dry it to make The sol is transformed into a strontium aluminum salt gel, and a uniformly mixed powder is obtained through steps such as heat treatment and grinding, and then further formed and sintered to obtain a flake batch material.

In comparison, using the traditional sol-gel method for chemical mixing can achieve molecular-level mixing of batch materials, but it is difficult to completely remove the water molecules in the gel even at high temperatures, resulting in residual residues in the sample. Hydroxyl, in addition, carbon in organic matter cannot be completely excluded. The residual hydroxyl groups and carbon have a great influence on the physical properties of the glass.

In addition, because the mass of each mixing is extremely small, and there are no ball mill jars and balls with small enough specifications, the ball mill method commonly used in industry is not suitable for mixing glass batch materials for laser levitation devices. Although the process of manual wet grinding using a mortar is relatively simple, due to the different density of raw materials and other reasons, there is often uneven dispersion of the mixture caused by stratification, which makes the error of this method extremely large, and the batch that meets the requirements cannot be obtained. In comparison, using the traditional sol-gel method for chemical mixing can achieve molecular-level mixing of batch materials, but it is difficult to completely remove the water molecules in the gel even at high temperatures, resulting in residual residues in the sample. In addition, the carbon in the strontium source organic matter cannot be completely eliminated; and the remaining part of the hydroxyl group and carbon have a greater impact on the physical properties of the glass.

Example 2

A method for preparing refractory oxide glass batch materials for laser heating suspension devices, taking the CaO-SrO-Al ₂ O ₃ ternary system as an example, the specific steps are as follows:

1) Using CaCO ₃ , SrCO ₃ and Al ₂ O ₃ powders as raw materials, weigh a total of 2 g of samples according to the formula that the molar ratio of CaO, SrO and Al ₂ O ₃ is 3:2:5;

2) Grind the mixed powder obtained in step 1) for the first time, pass the powder through a 10,000-mesh sieve, and then add glycerin liquid dispersion medium to the sieved powder, and the amount added is appropriate to completely cover the powder;

3) Place the solid-liquid mixture obtained in step 2) on a magnetic stirrer and stir for 4 hours;

4) Put the mixture obtained in step 3) into a heat treatment furnace at 570°C for 3 hours to keep the dispersion medium completely volatilized, and then grind for the second time to obtain a more uniform glass batch;

5) Put the glass batch material obtained in step 4) into the mold, and press it with a desktop electronic tablet press at a pressure of 15 MPa;

6) Pre-fire the flake glass batch obtained in step 5) in a heat treatment furnace at 1100°C for 1 hour, and then cool with the furnace to obtain a uniform flake glass batch.

Quantitative analysis is carried out in the same method as in Example 1. After calculation and comparison, the error between the result obtained by the method of the present invention and the design composition is less than 0.5%, which can meet the uniformity of the refractory oxide glass batch material used in the laser heating suspension device. requirements, the mixed method of this embodiment is feasible.

Example 3

A method for preparing refractory oxide glass batch materials for laser heating suspension devices, taking the MgO-SrO-Al ₂ O ₃ ternary system as an example, the specific steps are as follows:

1) Using MgO, SrCO ₃ and Al ₂ O ₃ powders as raw materials, weigh a total of 2 g of samples according to the formula that the molar ratio of MgO, SrO and Al ₂ O ₃ is 3:2:5;

2) Grind the three powders obtained in step 1) for the first time, pass the powder through a 10,000-mesh sieve, and then add polyethylene glycol liquid dispersion medium to the sieved powder, and the addition amount is suitable to completely cover the powder;

3) Place the solid-liquid mixture obtained in step 2) on a magnetic stirrer and stir for 3 hours;

4) Put the mixture obtained in step 3) into a heat treatment furnace at 560°C for 4 hours to keep the dispersion medium completely volatilized, and then grind for the second time to obtain a more uniform glass batch;

5) Put the glass batch obtained in step 4) into the mold, and press it with a desktop electronic tablet press at a pressure of 25 MPa;

6) Pre-fire the flake glass batch obtained in step 5) in a heat treatment furnace at 1030°C for 1 hour, and then cool with the furnace to obtain a uniform flake glass batch.

Quantitative analysis is carried out in the same method as in Example 1. After calculation and comparison, the error between the result obtained by the method of the present invention and the design composition is less than 0.4%, which can meet the uniformity of the refractory oxide glass batch used for laser heating suspension devices. requirements, the mixed method of this embodiment is feasible.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the creative concept of the present invention, some improvements and changes can also be made, and these all belong to the present invention scope of protection.

Claims (8)

1. a kind of preparation method of laser heating levitation device refractory oxides glass batch, it is characterised in that key step It is as follows：

A. it weighs：The refractory oxides powder mixed needed for precise, and first time grinding is carried out, after screening, mixed Powder, it is spare；

B. solid-liquid mixes：Liquid dispersion medium is added into the mixed-powder obtained alleged by step a, gained mixture is placed on magnetic force It is stirred evenly on blender；Wherein, viscosity contains only hydrocarbon oxygen to the liquid dispersion medium between 1 ~ 15mPas at normal temperatures Element, molecular weight are more than 90 and can all volatilize in subsequent step c；

C. it dries：Mixture obtained by step b is put into rise in heat-treatment furnace and is dried, decentralized medium is made to volatilize completely；Its In, drying temperature is so that the temperature that liquid dispersion medium volatilizees completely is advisable；

D. it grinds：Powder obtained by step d is carried out second to grind, obtains mixing uniform glass batch；

E. tabletting pre-burning：Glass batch obtained by step e is placed in mold, using tabletting machine, gained foliated glass is matched It closes and expects to be placed in heat-treatment furnace to be pre-sintered, obtain foliated glass batch.

2. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that mixed-powder grain size obtained by step a is not more than 1.5 μm.

3. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that the liquid dispersion medium in step b is one or both of glycerine or polyethylene glycol.

4. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that the liquid dispersion medium addition in step b is that mixed-powder is completely covered.

5. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that in step c, between drying temperature is 500 DEG C ~ 600 DEG C, drying time is 3 ~ 5 hours.

6. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that the pressure setting of tablet press machine described in step e is not less than 10Mpa.

7. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that pre-sintering process condition is in step e：It is warming up to not higher than each difficulty from room temperature with the rate of 5-20 DEG C/min Molten oxide ester mp temperature, then heat preservation 1-6 hours, then cool to room temperature with the furnace.

8. a kind of preparation side of laser heating levitation device refractory oxides glass batch according to claim 1 Method, it is characterised in that gained refractory oxides glass batch is suitable for the glass that the fusing points such as aluminate, gallate are higher than 1600 DEG C Glass system.