Co基金属玻璃的热膨胀与晶化动力学

Thermal Expansion and Crystallization Kineties of Co Based Meallic Glass

采用圆筒式试样膨胀试验方法研究了Co基金属玻璃条带的结构弛豫与晶化过程。试样的晶化发生在750K至900K的温度范围内,共有3个结晶相析出。主要结晶相为Co(4F)相。晶化产生的体积收缩约0.46％,占总的体积收缩的70％。测定不同升温速率Τ时的膨胀曲线,随Τ增加,膨胀系数α略为加大,由不同Τ时各膨胀峰的移动,分别求出各晶化阶段的表观激活能。

Tlie structure relaxation and crystallization process of Co based metal-lic glass is investigated by dilatation measurements using cylindric specimen.Crystallization may occur in the temperature tange of 750 K to 900 K and in three steps which correspond to the precipitations of crystalline phase more denselypacked than amorphous material. The activation energies for three stages of crystallization are determined from thermal dilatation curves.