CaCO3在铝熔体中的热分解特性及在泡沫铝制备中的应用

摘要

The thermal decomposition characteristics of CaCCh powders in aluminum melt and Nz were analyzed by the thermal analysis method. On the basis, foamed aluminum was prepared with CaCO3 as thickening and blowing agent. The results show that the decomposition temperature of CaCO3 in the aluminum melt was lower by 20--30℃ than that in N2, the decomposition was uniform and stable at the constant temperature of 700℃, which matched with the foaming temperature. During the foaming process of aluminum melt, CaCO3 decomposed to CO2 only, no CO. The foamed aluminum prepared by using CaCO3 as thickening and blowing agent had uniform porosity and spherical or near spherical pore structure.%通过热分析方法对CaCO3粉在铝熔体和氮气中的热分解特性进行了分析，在此基础上，采用CaCO3作为增黏发泡剂制备泡沫铝。结果表明：在铝熔体中，CaCO3连续升温分解反应温度比在氮气中的降低了20-30℃，在700℃恒温过程中分解匀速稳定，与泡沫化温度相匹配；铝熔体泡沫化过程中，CaCO3热分解只生成CO2而没有CO；采用CaCO3增黏发泡制备的泡沫铝，孔隙均匀，孔结构为球形或类球形。