Method for preparing glass ceramics

Abstract

The invention relates to a preparation method for glass ceramics. The preparation steps are as follows: firstly, selecting a raw material micro powder for forming glass ceramics, then adding an agent of fusion with weight percentage of 0-15%, and then adding a network modifier or crystal seed powder with weight percentage of 0-15%, performing even mixing, putting the mixture into a crucible, then performing melting at high temperature in a high-temperature electric furnace, taking out an obtained product and then pouring the obtained product into a mould and performing moulding and cooling, so as to obtain ordinary glass; secondly, cutting the glass into desired shapes and polishing the surface, then putting the polished glass in a high temperature work area of a common high-temperature electric furnace or ladder gradient-temperature electric furnace, placing electrodes onto parallel upper and lower surfaces of the glass or the crucible, applying a direct current electric field to assist directional crystallization treatment during crystallization of glass at medium temperature, wherein the electrostatic potential of the electric field is used as an auxiliary method to control grain nucleation and anisotropic growth; and thirdly, after the crystallization process is finished, performing cooling to form polar glass ceramics with the characteristics of a high devitrification volume fraction and high grain orientation. The method has the advantages of novel principle, reliable process, easy control as well as stable and reliable quality.

Description

[0001] Technical field: [0002] The invention belongs to the technical field of glass glue materials, and relates to a method for preparing polar glass-ceramics by using an electric field intervention auxiliary method, in particular to a method for preparing glass crystals. [0003] technical background: [0004] Polar glass-ceramics is a new type of composite functional material with non-ferroelectric polar crystallites such as piezoelectric and pyroelectric, which is obtained by controlled crystallization of molten amorphous inorganic materials. Its main feature is that the polar microcrystals are oriented along the C axis to generate spontaneous polarization. The main difference from ferroelectric ceramics is that they do not require external electric field polarization and have piezoelectric and pyroelectric characteristics. They are similar to piezoelectric single crystals and piezoelectric ceramics. Compared with ceramics and organic piezoelectric materials, piezoelectri...

AI Technical Summary

Problems solved by technology

In addition, there are also many explorations in the use of other auxiliary technical measures to promote the directional growth of crystallization in the process of material densification or crystallization. Some people use the magnetic field effect in a high temperature environment to affect the single crystal growth process in the melt; In the crystal preparation process, the flow state of the melt is suppressed by applying an axial magnetic field to reduce the oxygen concentration in the silicon single crystal and improve the quality of the silicon single crystal; A report on the preparation process of crystal glass; the performance of a material and the prospect of its practical application. The preparation process is a key factor. The progress of the preparation technology is likely to make a new breakthrough in the performance of the material. It is necessary to promote polar glass-ceramics However, it is still necessary to further develop its preparation technology, seek new technical principles and technical methods, regulate the assembly of microcrystalline grains in the glass phase matrix and the evolution of crystal form, and then achieve the strengthening of polar microcrystalline The purpose of grain oriented growth