二元硝酸盐的热物性测试及比热分析*

摘要

二元硝酸盐是非常重要的传热介质，通过熔融法制备混合盐试样，利用差示扫描量热法和蓝宝石法分别研究测定了 KNO 3-NaNO 2混合盐的热物性以及比热值。研究结果表明，二元硝酸盐具有较低的熔点和良好的热稳定性，适宜的工作温度在200~430℃之间。熔盐的比热值随成分不同有所变化，但在工作温度范围内变化很小。为熔盐的使用工艺改进提供了数据支持。%Binary nitrate salt was an important heat transfer medium.Mixed salt samples were prepared by mol-ten method.The thermal physics and specific heat capacity of the mixed salt consisted of KNO 3 and NaNO 2 were studied and measured separately by differential scanning calorimetry (DSC)and sapphire method.The re-sults showed that binary nitrate salt has low melting point and good thermal stability.The optimal operating temperature was between 200 and 430 ℃.The specific heat capacity of molten salt changes with the composition but changes little in the operating temperature.This experimental research provided data support for improving heat treatment process.