CN106116110A - The preparation method of chalcogenide glass - Google Patents

Abstract

The invention relates to a preparation method of chalcogenide glass, comprising the following steps: 1) weighing and mixing raw materials of chalcogenide glass under anhydrous and oxygen-free conditions, and transferring the mixed raw materials to a raw material purification-glass forming unit, Purification; 2) Heating up to 800-900°C and keeping warm to make the glass raw materials fully react to form a glass melt, which is filled with protective gas, and the glass melt flows to the glass clarification-homogenization unit through the feeding pipeline, and enters the glass homogenization unit after stirring. Chemical-forming unit; 3) Cool down to 400-500°C, and the fully stirred and uniform glass melt flows out through the bottom leakage pipe to obtain shaped products; 4) Anneal to obtain chalcogenide glass. The invention improves the optical uniformity, batch stability, glass output and production efficiency of chalcogenide glass products from raw material feeding, purification, glass formation, clarification, homogenization to forming continuous production.

Description

Preparation method of chalcogenide glass

technical field

The invention relates to the technical field of infrared glass preparation, in particular to a preparation method of chalcogenide glass.

Background technique

Chalcogenide glass refers to the glass formed by the elements of group VIA of the periodic table of elements S, Se, and Te as the main elements and a certain amount of other elements introduced. The currently widely used Ge-Sb-Se system chalcogenide glass has the following advantages: it has infrared transmission performance similar to that of single crystal germanium, and the transmission band covers three atmospheric windows; it has good light-thermal stability characteristics, and the refractive index The temperature coefficient is small and adjustable; the consumption of germanium resources is low, and it can be formed by precision molding technology, and the processing cost is low.

It is widely used in national defense technology fields such as individual helmet night vision system, gun sight, unmanned vehicle monitoring system and infrared guidance system. With the development of infrared detector technology and cost control, chalcogenide glass thermal imaging systems also have great application prospects in the fields of security, fire protection, temperature measurement, car night vision assisted driving, personal vision and smart phones. As the market demand for chalcogenide glass continues to increase, higher and higher requirements are put forward for its preparation technology, namely low cost, large batch and high performance.

At present, the atmosphere protection melting technology is used in the preparation method of chalcogenide glass, and the chalcogenide glass clinker is obtained by using the ampoule method, and the processes of feeding, glass formation, clarification, homogenization and leakage forming are completed sequentially at different times. However, this method cannot be produced continuously, and the production efficiency is still low, and raw materials are wasted, which increases the cost, and there are still certain differences in the stability of the obtained glass batches.

Contents of the invention

The main purpose of the present invention is to provide a new preparation method of chalcogenide glass. The technical problem to be solved is to make it continuously produced from raw material feeding, purification, glass formation, clarification, homogenization to forming, not only improving sulfur It not only improves the optical uniformity and batch stability of glass products, but also greatly improves the glass output and production efficiency, making it more suitable for engineering applications.

The purpose of the present invention and the solution to its technical problems are achieved by adopting the following technical solutions. A kind of preparation method of chalcogenide glass proposed according to the present invention, comprises the steps:

1) Weighing and mixing raw materials of chalcogenide glass under anhydrous and oxygen-free conditions with water content and oxygen content less than 3ppm, and transferring the mixed raw materials to a raw material purification-glass forming unit for purification;

2) Raise the temperature to 800-900°C and keep it warm so that the glass raw materials fully react to form a glass melt, which is filled with protective gas. The glass melt flows to the glass clarification-homogenization unit through the feeding pipeline, and enters the glass homogenization-homogenization unit after stirring. forming unit;

3) Cool down to 400-500°C, and the fully stirred and uniform glass melt flows out through the bottom leaking pipe to obtain shaped products; according to the shape and size of the final product, adjust the diameter of the leaking pipe and the temperature of the leaking material;

4) Annealing to obtain chalcogenide glass.

The purpose of the present invention and its technical problems can also be further realized by adopting the following technical measures.

Preferably, the aforementioned method for preparing chalcogenide glass, wherein the glass raw material in step 1) has a purity higher than 99.999%, and a material particle size of 2-10mm.

Preferably, the aforementioned method for preparing chalcogenide glass, wherein, the mixed raw material described in step 1) is mixed with an oxygen scavenger Al with a purity ≥ 99.999%, and its doping amount is 0.05-0.1‰ of the total weight of the mixed raw material .

Preferably, the aforementioned method for preparing chalcogenide glass, wherein the raw material purification vacuum degree in step 1) is less than 10 ⁻² Pa, the heating temperature is 300-400° C., and the heating time is 5-10 hours.

Preferably, in the aforementioned method for preparing chalcogenide glass, wherein, the glass melt formation process described in step 2) is completed in the raw material purification-glass formation unit, the process is that after the raw material purification is completed, the temperature of the unit is raised to 800-900℃, the holding time is 10-20h, and the vacuum degree is less than 10 ^-2 Pa.

Preferably, the aforementioned method for preparing chalcogenide glass, wherein, after the glass melt is formed in step 2), the raw material purification-glass forming unit is filled with protective gas, and the protective gas is nitrogen or helium , wherein the oxygen content and water content in the protective gas are less than 3ppm.

Preferably, in the aforementioned method for preparing chalcogenide glass, the pressure in the glass refining-homogenizing unit and the glass homogenizing-forming unit described in step 2) is 0.2-0.3 MPa, and the pressures of the two are consistent.

Preferably, in the aforementioned method for preparing chalcogenide glass, the shape of the shaped product described in step 3) is a strip shape, a plate shape or a curved surface shape.

Preferably, in the aforementioned method for preparing chalcogenide glass, the lower end of the leakage tube described in step 3) is protected by a slightly positive pressure atmosphere.

Preferably, the aforementioned method for preparing chalcogenide glass, wherein the protective atmosphere is 0.12-0.15 MPa of nitrogen or helium.

By virtue of the above technical solution, the preparation method of chalcogenide glass of the present invention has at least the following advantages:

(1) The continuous production method is adopted, the production capacity is greatly increased, and the daily production capacity is more than 100 kilograms;

(2) Complete raw material purification and glass formation under vacuum-tight conditions, so that highly volatile glass raw materials can fully react with other raw materials to form a glass melt, reducing abnormal volatilization of raw materials; under positive pressure atmosphere protection conditions, complete glass The clarification, homogenization and forming of the liquid further control the volatilization of the glass melt. In the continuous production state, the two measures comprehensively ensure the consistency of the glass composition and performance, improve the batch stability, and the refraction of different batches The rate difference is less than 1×10 ^-3 ;

(3) In the process of clarification, homogenization and leakage forming, mechanical stirring is used to obtain a more uniform glass melt, which reduces defects such as glass streaks and stones, and ensures the optical uniformity of the glass product, and the refraction of the same piece of glass The rate difference is less than 1×10 ^-4 ;

(4) The continuous production of each unit avoids the one-time consumption of the quartz container, the production cost is mostly reduced, and the efficiency is significantly improved.

(5) By changing the mold shape, forming parameters, etc., glass blanks in the form of strips, plates, and curved surfaces can be easily formed, and the combination of precision molding technology can further reduce the production cost of chalcogenide glass components.

The above description is only an overview of the technical solutions of the present invention. In order to understand the technical means of the present invention more clearly and implement them according to the contents of the description, the preferred embodiments of the present invention and accompanying drawings are described in detail below.

Description of drawings

Fig. 1 is a flow chart of the production process of continuous melting and leak forming chalcogenide glass of the present invention.

Fig. 2 is a device diagram of the continuous melting and leakage forming equipment of the present invention.

Fig. 3 is the infrared spectrum measurement result of the chalcogenide glass produced in Example 3.

detailed description

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the following is a detailed description of the preparation method of the continuous melting and leakage forming chalcogenide glass according to the present invention in conjunction with the accompanying drawings and preferred embodiments. Embodiments, structures, features and effects thereof are described in detail below. In the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any manner.

As shown in Fig. 1, one embodiment of the present invention proposes a kind of preparation method of continuous melting and leakage forming chalcogenide glass, which comprises the steps:

1) Raw material weighing: According to the design ratio, weigh the required amount of glass raw materials in an anhydrous and oxygen-free glove box, and mix them to form a glass batch. The purity of the glass raw material used is higher than 99.999%, and the particle size of the material is 2-10mm; the weighed batch material is put into a quartz container and sealed. Further, an oxygen scavenger Al with a purity ≥ 99.999% is added to the glass batch material, and the doping amount is 0.05-0.1‰ of the total weight of the batch material;

2) Purification of raw materials: Open the valve at the upper end of the quartz container, inject the required batch materials into the raw material purification and formation unit, vacuumize and heat the raw material purification and formation unit, the heating temperature is 330-400°C, and the vacuum degree is ≤1×10 ^-2 Pa, purification time is 5~10h, remove water and oxygen;

3) Glass formation: after the raw material purification is completed, close the valve of the raw material purification and synthesis unit, keep the vacuum inside it, and continue to heat up to the glass formation temperature, the temperature range is 800-900°C, and the holding time is 10-20h , so that the glass batch material is fully combined to form a glass melt. After the glass melt is formed, the raw material purification and synthesis unit is filled with protective gas to make the pressure inside the unit reach 0.2MPa-0.3MPa. The protective gas can be nitrogen, helium, etc., and the oxygen content and water content in the protective gas should be controlled below 3ppm;

4) Glass clarification: open the feed pipeline of the raw material purification and synthesis unit and the glass clarification-homogenization unit, so that the glass melt flows to the glass clarification homogenization unit, and continue to maintain the high temperature state of the glass liquid in the clarification homogenization unit, At the same time, a stirrer is used to continuously stir the molten glass at the front of the clarifying and homogenizing unit, and the stirred molten glass flows to the rear section and directly enters the glass homogenizing and forming unit;

The raw materials continue to react at 800-900°C, and the bubbles in the glass melt can be eliminated by stirring, so as to achieve the effect of glass clarification;

5) Glass homogenization and forming: The molten glass flowing from the glass clarification and homogenization unit gradually cools down to the forming temperature of 400-500°C in the glass homogenization and forming unit, and flows out through the bottom leakage pipe. According to the final product shape and Dimensions, adjust the diameter of leakage pipe, leakage temperature, etc. accordingly;

6) Glass annealing: After the glass melt is formed into the specified shape and size, rough annealing is carried out in the tunnel annealing furnace with chain belt transmission, and the glass blank is reduced by gradient cooling. At the end of the tunnel annealing furnace, after rough annealing The final glass blank is sent into the precision annealing furnace for further precision annealing.

The equipment for continuous melting and leakage forming of chalcogenide glass is shown in Figure 2, including: raw material purification-glass forming unit 1, glass clarification-homogenization unit 2, homogenization unit 3, leakage forming unit 4, chain belt Type annealing furnace 5. According to production capacity requirements, the continuous smelting equipment may include multiple sets of raw material purification-glass forming units, and quartz glass stirring devices are installed in the glass clarification-homogenization unit and homogenization-forming unit, and the front section of the chain-belt annealing furnace is equipped with Quartz glass forming mold, and polishing treatment on the contact surface with chalcogenide glass.

During the forming process of glass leakage, the lower end of the leakage opening is protected by a slightly positive pressure atmosphere to prevent the newly formed glass from reacting with external impurities at high temperature and affecting the purity of the glass.

Example 1

An embodiment of the present invention proposes a method for preparing Ge ₂₂ As ₂₀ Se ₅₈ chalcogenide glass by continuous melting and leakage forming.

(1) Raw material weighing: Prepare three batches with a total weight of 30kg in an anhydrous and oxygen-free environment, and add them to three sets of raw material purification-glass forming units respectively. The dimensions of the dehydroxylated quartz crucible used are Φ160mm*H400mm*δ5mm;

(2) Purification of raw materials: close the top and bottom discharge valves of the quartz crucible, vacuumize the quartz crucible and heat it outside, so that the temperature of the raw materials in the crucible reaches 320°C, the vacuum degree is less than 1×10 ^-2 Pa, and continue to bake 5 hours;

(3) Glass formation: close the quartz crucible and the external valve, further heat the batch material in the quartz crucible to 850°C, and keep it at this temperature for 20 hours to fully combine the glass batch material to form a glass melt. After the glass melt is formed, the raw material purification and synthesis unit is filled with high-purity nitrogen to make the pressure in the unit reach 0.23MPa.

(4) Glass clarification: Utilize resistance heating to open the feed pipes of the raw material purification and synthesis unit and the glass clarification-homogenization unit, so that the glass melt flows to the glass clarification-homogenization unit under the action of its own gravity, before clarification - The temperature in the homogenization unit is 870°C, the pressure is 0.23MPa, and the high-temperature state of the molten glass is continuously maintained. At the same time, the molten glass is continuously stirred at the front of the clarification-homogenization unit with a stirrer, and the stirred glass The liquid flows to the rear section and directly enters the glass homogenization-forming unit.

(5) Glass homogenization and forming: use resistance heating to open the glass clarification-homogenization unit and the leakage forming unit and the material delivery pipeline, and the glass liquid in the rear section of the glass clarification-homogenization unit uses the principle of a connector to continuously flow The flow into the homogenization-forming unit, the temperature in the homogenization-forming unit is set at 430°C±10°C, the external dimensions of the unit are Φ130mm*H600mm*δ5mm, and flow out through the bottom leakage pipe, the leakage pipe The inner diameter of the mold is 8mm, and the formed product is a strip blank, the size is W40mm×H20mm, and the length direction can be cut at will.

(6) Glass annealing: the strip glass blank of W40mm×H20mm is roughly annealed in the tunnel annealing furnace driven by the chain belt, the temperature of the first section of the chain belt is 300 ℃, the temperature of the end is 200 ℃, The length is 8m, and the running speed is 1m/h. At the end of the chain-belt annealing furnace, cut the strip-shaped glass blanks to a suitable length, and send them into the precision annealing furnace with a temperature of 200°C. According to the volume of the precision annealing furnace , start the heating program after full, the temperature of the precision annealing furnace will be raised to 290°C after 1h, after holding at this temperature for 10h, cool down to 200°C at a cooling rate of 5°C/h, then turn off the power of the annealing furnace, cool down to room temperature naturally, take out The blank is subjected to subsequent processing.

One piece of glass 40mm×40mm×20mm was taken and polished on both sides, and its optical uniformity ΔN was tested to be 38.9×10 ^-6 .

Example 2

An embodiment of the present invention proposes a method for preparing Ge ₂₈ Sb ₁₂ Se ₆₀ chalcogenide glass by continuous melting and leakage forming.

(1) Raw material weighing: Prepare three batches with a total weight of 30kg in an anhydrous and oxygen-free environment, and add them to three sets of raw material purification-glass forming units respectively. The dimensions of the dehydroxylated quartz crucible used are Φ160mm*H400mm*δ5mm;

(2) Purification of raw materials: close the top and bottom discharge valves of the quartz crucible, vacuumize the quartz crucible and heat it outside, so that the temperature of the raw materials in the crucible reaches 320°C, the vacuum degree is less than 1×10 ^-2 Pa, and continue to bake 5 hours;

(3) Glass formation: close the quartz crucible and the external valve, further heat the batch material in the quartz crucible to 860°C, and keep it at this temperature for 20 hours to fully combine the glass batch material to form a glass melt. After the glass melt is formed, the raw material purification and synthesis unit is filled with high-purity nitrogen to make the pressure in the unit reach 0.23MPa.

(4) Glass clarification: Utilize resistance heating to open the feed pipes of the raw material purification and synthesis unit and the glass clarification-homogenization unit, so that the glass melt flows to the glass clarification-homogenization unit under the action of its own gravity, before clarification -The temperature in the homogenization unit is 860°C, the pressure is 0.23MPa, continue to maintain the high temperature state of the molten glass, and at the same time use a stirrer to continuously stir the molten glass at the front of the clarification-homogenization unit, and the stirred glass The liquid flows to the rear section and directly enters the glass homogenization-forming unit.

(5) Glass homogenization and forming: use resistance heating to open the glass clarification-homogenization unit and the leakage forming unit and the material delivery pipeline, and the glass liquid in the rear section of the glass clarification-homogenization unit uses the principle of a connector to continuously flow The flow into the homogenization-forming unit, the temperature in the homogenization-forming unit is set at 450°C±10°C, the external dimensions of the unit are Φ130mm*H600mm*δ5mm, and flow out through the bottom leakage pipe, the leakage pipe The inner diameter is 10mm, and the formed product is a disc-shaped blank with a size of Φ140mm×H30mm.

(6) Glass annealing: Φ140mm×H30mm disc-shaped glass blanks are roughly annealed in a chain-belt-driven tunnel-type annealing furnace. The total length is 8m, and the running speed is 1m/h. At the end of the chain belt type annealing furnace, cut the strip glass blanks to a suitable length, and send them into the precision annealing furnace with a temperature of 200°C. According to the precision annealing furnace After the volume is full, start the heating program. After 1 hour, the precision annealing furnace will heat up to 295°C. After holding at this temperature for 10 hours, it will cool down to 200°C at a cooling rate of 5°C/h. After that, turn off the power of the annealing furnace and cool down to room temperature naturally. Take out the blank for subsequent processing.

One of the wafers was randomly selected, and the optical uniformity ΔN was tested to be 97.7×10 ^-6 after double-sided polishing.

Example 3

An embodiment of the present invention proposes a method for preparing As ₄₀ Se ₆₀ chalcogenide glass by continuous melting and leakage forming, as shown in FIG. 2 , the device and process layout.

(1) Raw material weighing: Prepare three batches with a total weight of 30kg in an anhydrous and oxygen-free environment, and add them to three sets of raw material purification-glass forming units respectively. The dimensions of the dehydroxylated quartz crucible used are Φ160mm*H400mm*δ5mm;

(2) Purification of raw materials: close the top and bottom discharge valves of the quartz crucible, vacuumize the quartz crucible and heat it outside, so that the temperature of the raw materials in the crucible reaches 320°C, the vacuum degree is less than 1×10 ^-2 Pa, and continue to bake 5 hours;

(3) Glass formation: close the quartz crucible and the external valve, further heat the batch material in the quartz crucible to 800°C, and keep it at this temperature for 20 hours to fully combine the glass batch material to form a glass melt. After the glass melt is formed, the raw material purification and synthesis unit is filled with high-purity nitrogen to make the pressure in the unit reach 0.23 MPa.

(4) Glass clarification: Utilize resistance heating to open the feed pipes of the raw material purification and synthesis unit and the glass clarification-homogenization unit, so that the glass melt flows to the glass clarification-homogenization unit under the action of its own gravity, before clarification -The temperature in the homogenization unit is 820°C, the pressure is 0.23MPa, continue to maintain the high temperature state of the molten glass, and at the same time use a stirrer to continuously stir the molten glass at the front of the clarification-homogenization unit, and the stirred glass The liquid flows to the rear section and directly enters the glass homogenization-forming unit.

(5) Glass homogenization and forming: use resistance heating to open the glass clarification-homogenization unit and the leakage forming unit and the material delivery pipeline, and the glass liquid in the rear section of the glass clarification-homogenization unit uses the principle of a connector to continuously flow The flow into the homogenization-forming unit, the temperature in the homogenization-forming unit is set at 360°C±10°C, the external dimensions of the unit are Φ130mm*H600mm*δ5mm, and flow out through the bottom leakage pipe, the leakage pipe The inner diameter of the glass is 8mm, and the molten glass flows into the mold at the lower end. The mold stays under the leakage pipe for 10 seconds, and then moves into the pressing process. , ready for the next set of suppression. The female mold carries the chalcogenide glass element of the mold into the chain-belt annealing furnace for annealing.

(6) Glass annealing: the female mold and the chalcogenide glass blank in the mold are roughly annealed in the tunnel annealing furnace driven by the chain belt. The total length is 8m, and the running speed is 1m/h. At the end of the chain-belt annealing furnace, the curved glass blank is taken out and placed in a precision annealing furnace at 50°C. After it is full, the heating program is started, and it is precision annealed after 4 hours. The furnace is heated to 190°C, and after being kept at this temperature for 10 hours, the temperature is lowered to room temperature at a cooling rate of 3°C/h, and then the blank is taken out for subsequent precision machining.

The infrared spectrum measurement results of the produced chalcogenide glasses are shown in Fig. 3.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still belong to the present invention. within the scope of the technical solution of the invention.

Claims (10)

1. a preparation method of chalcogenide glass, is characterized in that, comprises the steps: 1) Under anhydrous and oxygen-free conditions where the water content and oxygen content are both less than 3ppm, weigh and mix the raw materials of chalcogenide glass, and transfer the mixed raw materials to the raw material purification-glass forming unit for purification; 2) Raise the temperature to 800-900°C and keep it warm so that the glass raw materials fully react to form a glass melt, which is filled with protective gas. The glass melt flows to the glass clarification-homogenization unit through the feeding pipeline, and enters the glass homogenization-homogenization unit after stirring. forming unit; 3) Cool down to 400-500°C, and the fully stirred and uniform glass melt flows out through the bottom leaking pipe to obtain shaped products; according to the shape and size of the final product, adjust the diameter of the leaking pipe and the temperature of the leaking material; 4) Annealing to obtain chalcogenide glass. 2. The method for preparing chalcogenide glass according to claim 1, characterized in that the glass raw material in step 1) has a purity higher than 99.999%, and a material particle size of 2-10mm. 3. The preparation method of chalcogenide glass according to claim 1, characterized in that, in the mixed raw material described in step 1), an oxygen scavenger Al with a purity ≥ 99.999% is added in an amount equal to the total amount of the mixed raw material 0.05-0.1‰ of weight. 4. The method for preparing chalcogenide glass according to claim 1, characterized in that the raw material purification vacuum degree in step 1) is less than 10 ^-2 Pa, the heating temperature is 300-400°C, and the heating time is 5-10h . 5. The preparation method of chalcogenide glass according to claim 1, characterized in that, the glass melt formation process described in step 2) is completed in the raw material purification-glass formation unit, and its process is after completing the raw material purification, making The temperature of the unit is raised to 800-900°C, the holding time is 10-20h, and the vacuum degree is less than 10 ^-2 Pa. 6. The preparation method of chalcogenide glass according to claim 1, characterized in that, after the glass melt is formed in step 2), the raw material purification-glass forming unit is filled with protective gas, and the protective gas The gas is nitrogen or helium, wherein the oxygen content and water content in the protective gas are less than 3ppm. 7. The preparation method of chalcogenide glass according to claim 1, characterized in that, the pressure in the glass clarification-homogenization unit and glass homogenization-forming unit described in step 2) is 0.2-0.3MPa, and Both have the same pressure. 8. The method for preparing chalcogenide glass according to claim 1, characterized in that the shape of the shaped product described in step 3) is strip, plate or curved. 9. The preparation method of chalcogenide glass according to claim 1, characterized in that, the lower end of the leakage pipe described in step 3) is protected by a slightly positive pressure atmosphere. 10. The method for preparing chalcogenide glass according to claim 9, characterized in that, the protective atmosphere is 0.12-0.15MPa nitrogen or helium.