Ultra-low-expansion glass ceramic for laser gyro and preparation method thereof

Abstract

The invention provides an ultra-low-expansion glass ceramic for a laser gyro and a preparation method thereof, wherein, the ultra-low-expansion glass ceramic includes the following ingredients according to mass percentages: 56-68% of SiO2, 21-27% of Al2O3, 2-4% of Li2, 0-1% of Na2, 0-1% of K2, 0-3% of MgO, 0-1.5% of ZnO, 4.5-6.8% of P2O5, 1-2.5% of TiO2, 1-2.5% of ZrO2 and 0.5-1.5% of Sb2O3 / As2O3; the principal crystalline phase is beta quartz solid solution; the crystalline phase content is 70-85%; the grain size is lower than 50nm; and the magnitude order of coefficient of heat expansion is 10<-8>. The preparation method comprises the steps of dosing, mixing, melting, evening, clarifying, glass moulding, annealing and sitallization heat treatment, wherein, the steps of melting, evening and clarifying are carried out at 1570-1590 DEG C; the sitallization heat treatment comprises the steps as follows: the materials are crystallized after 6-10 hours of warm keeping at nucleating temperature of 650-750 DEG C with crystallizing rate of 1 DEG C / min; the crystallizing temperature is 750-850 DEG C; and the warm-keeping time is 6-10 hours. The buckling strength of the ultra-low expansion glass ceramic is higher than 170MPa; the process roughness is higher than 2-star; and the spectrum transmittance is more than 90% within the waveband of 0.6-2mum. In addition, the ultra-low-expansion glass ceramic has excellent hardness and abrasion resistance.

Description

technical field [0001] The invention relates to an ultra-low-expansion glass-ceramic and a preparation method thereof, in particular to an ultra-low-expansion glass-ceramic for a laser gyroscope and a preparation method thereof for manufacturing a laser gyroscope resonator frame and a laser gyroscope reflector. Background technique [0002] In recent years, due to the development of inertial guidance technology, the laser gyroscope, as its core component, has also developed rapidly. The laser gyroscope has the advantages of short start-up time, strong impact resistance, high reliability, and long life. It is being used in different fields. Gradually replace the traditional electromechanical gyroscope. Since the laser gyroscope needs to meet the use under different conditions, it also puts forward extremely stringent requirements for its constituent materials. Transmittance, high uniformity, and at the same time, because the laser gyroscope resonator skeleton needs to be pro...

AI Technical Summary

Problems solved by technology

Domestic existing two Chinese patent applications whose publication numbers are respectively CN1944300A and CN1847182A relate to this ultra-low expansion glass-ceramic. The flux of the glass, its effect is to reduce the hardness of the glass while fluxing, which is not good for the mirror polishing and anti-wear of the laser gyro frame

According to reports, glass-ceramics usually use center stirring technology in the melting process of basic glass, but this center stirring technology is often difficult to eliminate the center stripes of formed glass-ceramics, which seriously affects the quality of glass

So far, there is no report on the ultra-low expansion glass-ceramic and its preparation method that can eliminate the center stripe of the formed glass-ceramics and meet the requirements for the preparation of the laser gyroscope resonant cavity skeleton and the laser gyroscope mirror.