以氯化钠作为共晶盐研究对象,探讨共晶盐反复多次的低温液-固相变后的晶体变化趋势。通过X射线衍射仪对试样相变前后的晶体的晶面间距、粒径等参数进行分析,判断其晶体结构的变化趋势。同时通过同步热分析仪、电导率仪分析试样相变前后的潜热、电导率的变化趋势。分析结果表明,共晶盐经过反复多次的相变后,晶体粒径从微米级逐渐向纳米级转变,有向无定形非晶体转化的趋势;同时,相变温度、潜热与电导率呈下降趋势。

Sodium chloride was researched as the eutectic salt, and its crystal change after cryogenic repeated liquid-solid phase transition was analyzed by using an X-ray diffractometer. The analysis results show that the crystal grain size changes from micron to nanoscale, having the trend to form amorphous. At the same time, phase-transition temperature, latent heat and conductivity were declining.