一种易碎玻璃转变温度的研究

STUDY OF THE TRANSITION TEMPERATURE OF A BREAKAWAY GLASS

利用超声相比较和相位探测法,测量了一种易碎玻璃纵波和横波声速从室温到73℃范围内的变化,由此得到弹性模量随温度的变化规律.发现声速和弹性模量随温度变化曲线的斜率在54℃附近有明显变化,存在一个转变温度点,测是结果与布里渊散射在此温区相应的数据符合.研究表明,这个转变温度是易碎玻璃完全熔化前的玻璃化转变温度,比其它玻璃低得多.

Using ultrasonic phase comparison and phase detection method, the longitudinal and shear sound velocities and their temperature dependences of a breakaway glass have been measured up to 73℃. The elastic moduli, such as bulk modulus, Young's modulus and Poisson's ratio have been determined. The results indicate that this breakaway glass exhibits a turning point in the velocites and elastic moduli vs, temperature curves at about 54℃. The measured values are in good agreement with Brillouin scattering data at this range of temperature. The study shows that this turning point of temperature is a point induced by the strain before the material goes to total melting, we always call it glass transition temperature. However it is much lower than other materials.