Preparation method of large-size chalcogenide infrared glass based on salt bath quenching method

Abstract

The invention relates to the technical field of infrared material production, in particular to a method for preparing large-size chalcogenide infrared glass based on the salt bath quenching method. The chalcogenide infrared glass produced with the method has the advantages of being rapid in heat dissipation, small in brittleness and not prone to crack. According to the method, the large-size chalcogenide infrared glass is prepared with the salt bath rapidly-quenching method, a salt solution including 55% of KNO3 and 45% of NaNO2 is used as a cooling medium, and a high-temperature glass melt at the temperature of 800 DEG C or above is rapidly cooled within the temperature range from 150 DEG C to 350 DEG C; as the temperature section of 150-350 DEG C is lower than the devitrification temperature of the chalcogenide infrared glass, it can be guaranteed that the infrared glass with the good performance is obtained. A chalcogenide glass bar sample with the diameter of 50 mm is prepared with the method and is complete in structure, bright in surface and good in glass forming performance, and the transmittance of infrared rays within the range from 2 microns to 15 microns is 60% or above.

Description

1. Technical field: [0001] The invention relates to the technical field of infrared material production, in particular to a method for preparing large-sized chalcogenide infrared glass based on a salt bath quenching method. 2. Background technology: [0002] Chalcogenide glass has the characteristics of small thermal difference coefficient, wide spectral transmittance and excellent chemical stability. It is suitable for batch production of various infrared lenses by precision molding, and its production cost is lower than that of single crystal or polycrystalline materials. More importantly, S, Se, and Te can form stoichiometric or non-stoichiometric glasses with other elements, giving them the advantage of continuously tunable properties. Therefore, since the successful preparation in the 1950s, chalcogenide glasses have been successively adopted in infrared optical systems. With the development of focal plane array and uncooled detector technology, chalcogenide glass has ...

AI Technical Summary

Problems solved by technology

Batch melts encapsulated in evacuated quartz tubes can form glass when quenched in air at a relatively slow rate, or by water cooling, however, due to the large size of the sample, if air cooling is used, the material interior The cooling rate is obviously much smaller than that of the outside, resulting in poor uniformity of the optical and mechanical properties of the glass; if water cooling is used, the glass is very easy to burst due to the fast surface cooling rate, and the sample diameter exceeds 1cm. It is difficult to ensure the integrity, especially for large-sized chalcogenide glass, the temperature difference between the inside and the outside is large during the quenching process, the heat transfer rate is poor, and the internal stress of the melt is large after forming a block

Therefore, the preparation of large-size chalcogenide glass technology is rarely seen in the world at present, so the preparation of large-size chalcogenide glass plays a vital role in the development of infrared technology

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