Study On Crystallization Kinetics Of Dy³⁺/Tb³⁺Doped Aluminum Borosilicate Glass

In recent years,with the development of new technologies such as laser,computer,information and optical fiber communication,the research and application of magneto-optical effect has been developing to the depth and breadth.So many new magneto-optical materials and magneto-optical devices have emerged.In this paper,aluminum borosilicate glass is selected as matrix glass with different content of Dy³⁺and Tb³⁺doped.This glass has magnetic and optical properties,which belongs to a kind of magneto-optic glass.The purpose of this study is to discuss a kind of high performance magneto-optic glass.At the same time,the crystallization kinetics of the glass is studied and its crystallization behavior is analyzed.The main contents of this paper are as follows:The Dy³⁺/Tb³⁺doped aluminum borosilicate system magneto-optical glass was prepared by high temperature melting and cooling process.The crystallization peak temperature of the glass was determined by differential scanning calorimetry.The precipitated crystal is obtained by heat treatment at the crystallization temperature.According to the Kissinger equation,the crystallization kinetics parameters and the transformation kinetic parameters of different rare earth ions were calculated.The calculation shows that when the concentration of rare earth ions is 25 mol%,the corresponding crystallization activation energy and the activation energy of glass transition are 532.79 k J/mol and 413.22 kJ/mol,respectively.The average crystallization index is 0.8.When the concentration of rare earth ions increases to 33 mol%,the crystallization activation energy and transition activation energy are 327.83 kJ/mol and 323.82k J/mol respectively.Comparing with the above parameters,it is known that the activation energy and activation energy of transformation decrease with the increase of the doping amount of rare earth ions,indicating that the greater the concentration of rare earth ions,the more unstable the glass is.The magneto-optic glass doped with different rare earth ions was treated by heat preservation,and the coefficient of expansion,density and stability before and after crystallization were compared.Firstly the precipitated crystal X ray diffraction analysis,determine the precipitated crystal is mainly TbBO₃,and then after the glass crystallization expansion test,found before and after crystallization with increasing TbBO₃ doping amount,expansion coefficient decreases,the density increases gradually after the crystallization expansion coefficient and density of the whole is greater than the crystallization front;acid resistant glass crystallization before than after the crystallization of acid resistant,alkali resistance after the crystallization is greater than the alkali resistance before crystallization.Study on optical properties of glass before and after crystallization,found that with the increase of Tb₂O₃ content,the absolute value of the Verdet constant of magneto-optic glass increases linearly,the magneto-optical effect that is the higher content of Tb³⁺glass is more obvious;the glass crystallization before the excitation intensity and luminous intensity is greater than the glass after the crystallization,in intensity under the excitation of 375 nm glass substrate with increasing Tb³⁺content first increased and then decreased,and reached the maximum when the content of Tb₂O₃ is 35 mol%,far more than the general magneto-optical glass.Under the excitation of ultraviolet light,the magneto-optical glass containing Tb³⁺ion has yellow and green light before and after the crystallization.Analyzing the crystallization kinetics of magneto-optic glass,and analyzing the physicochemical and optical properties before and after crystallization,it has a good reference value in the actual production of magneto-optic glass.