【摘要】 用熔融退火方法制备无碱SiO2-B2O3-Al2O3-RO(R=Mg,Ca,Sr,Ba)系玻璃。玻璃的成分范围以摩尔计为:SiO2,64.17%～70%;B2O3,7%～14.12%;Al2O3,9.88%～16.94%;RO总量,12%(2.4%MgO,4.8%CaO,2.4%SrO,2.4%BaO)。用Fourier变换红外光谱研究了上述玻璃系统结构随成分的变化规律,同时,对玻璃结构与热膨胀系数、密度等物理性质的关系也进行了研究。结果表明:在Al含量较高的铝硼硅系玻璃中,B更多的以[BO3]形态存在。随着SiO2和B2O3摩尔比的增大,[BO3]的量有所减少,而热膨胀系数呈增加趋势,密度出现极大值。随着Al2O3和B2O3摩尔比的增大,[BO3]的量出现极值,热膨胀系数也出现极值,密度总体趋势是增加的。铝硼硅系玻璃的热膨胀系数、密度等物理性质与玻璃结构密切相关。更多还原

【Abstract】 Alkali-free aluminoborosilicate glasses SiO2-B2O3-Al2O3-RO(R=Mg,Ca,Sr and Ba)were prepared by the melt annealing method.The range of glass components in the mole fraction were as follows:SiO2,64.17%—70%,B2O3,7%—14.12%,Al2O3,9.88% —16.94%,total RO,12%(2.4% MgO,4.8% CaO,2.4% SrO,2.4% BaO).The changes of glass structure with varying components were investigated by using the Fourier transform infrared spectra.The relationship between the glass structure and physical properties,such as thermal expansion coefficient and density,was also investigated.The results show that in this kind of aluminoborosilicate glass with large amounts of alumina,the boron mainly existed as a BO3 unit.Furthermore,when the mole ratio of SiO2/B2O3 in-creases,the fraction of the BO3 unit decreases,the thermal expansion coefficients increase,and the densities reach a maximum value.When the mole ratio of Al2O3/B2O3 increases,the fraction of the BO3 unit reaches the maximum value,the thermal expansion coef-ficients also reach the maximum value,and the whole trend of densities increases.There is close connection between the structure and the physical properties,i.e.,thermal expansion and density etc.of the aluminoborosilicate glasses.更多还原