论文部分内容阅读
采用未饱和水溶液法并利用超声波的震荡与分散的原理制备了[KNO3-NaNO3-Ca(NO3)2]/膨胀石墨复合相变储热材料,对样品做了导热系数、DSC、XRD和SEM等表征分析.通过添加不同质量分数的膨胀石墨(EG),研究了添加量对复合相变储热材料热物性能的影响.结果表明,利用未饱和水溶液法并利用超声波的震荡与分散的原理制备的复合相变材料的微观结构均一、稳定,导热系数增加更为明显,30％(质量分数)EG的复合相变材料导热系数可达24.29 W/(m·K),比纯共晶盐导热系数提高了67倍;EG质量分数小于10％时,共晶盐不能完全浸透到膨胀石墨空隙中,有明显的相分离,不能形成稳定的复合相;另外,EG含量越多,复合相变材料的导热系数就越大.“,”The KNO3-NaNO3-Ca (NO3) 2/expanded graphite (EG) composite phase change materials (PCM) were successfully prepared by means of unsaturated water solution method combined with ultrasonic radiation,which were then characterized by means of thermal conductivity,DSC,XRD,and SEM.By adding EG with different mass fractions,the effect of adding contents on performance of the composition PCM was studied.Results showed that the composition PCM had uniform microstructure,and its thermal conductivity could be greatly improved,thermal conductivity of the composition PCM with 30％ (mass fraction) EG was up to 24.29 W/(m·K),67 times higher than that of pure eutectic salt.When the EG mass fraction was less than 10％,eutectic salt could not totally permeate into the gaps of EG,there was obvious phase separation,and the stable composite phase cannot be formed.In addition,the thermal conductivity of the composition PCM raised with the increasing of EG proportion.