中文摘要：

钾明矾（KAl（SO4）2·12H2O）有较高的潜热和良好的导热性（熔化热232．4kJ／kg，导热系数为0．55W／m·K），熔点为91℃，是中低温相变材料中较有开发价值的一种。但是它的过冷度高达19．8℃，并且由于相变过程伴随着结晶水的蒸发使无机盐的使用寿命大大降低。本文通过冷指法及添加成核剂的方法对硫酸铝钾的过冷现象进行了研究，结果表明成核剂NiSO4·6H2O、MgCl2·6H2O能较好的改善过冷现象，当MgCl2·6H2O的添加量为2％时可使过冷度降为零，且能保持钾明矾的相变温度而不使其降低。利用MgCl2·6H2O具有很强的吸湿性，可以补充相变过程中损失的水分，使相变材料的使用寿命大大提高。

英文摘要：

Aluminum potassium sulfate（ KAl（ SO4 ） 2·12H2O ） is one of inorganic hydration phase change material. It has a higher latent heat and good heat conduction （ melting heat is 232.4kJ/kg, the thermal conductivity is 0.55W/m· K）. The pure potassium aluminium sulfate melting temperature is 91℃. So it has the development value in the heat storage material of moderate temperature. But its supercooling reaches to 19.8℃ ,and its life-span greatly reduce because of evaporation of crystal water during the phase change process. This paper studys on its supercooling by fingering cold method and nucleating tests, the results show that nucleating agent of NiSO4·6H2O and MgCl2·6H2O can improve the supercooling very well. The supercooling reduce to zero when 2% MgCl2·6H2O added, and the phase change temperature of potassium aluminium sulfate retains affer adding. Its life-span is improved greatly because the strong hygroscopicity of MgCl2·6H2O can compensate water loss during phase change process.