以硫酸盐为原料,用高温固相反应法制得性能优良的MgAI_2O_4尖晶石超微粉,运用TGA/DTA,XRD,SEM等手段研究了尖晶石的形核生长过程及相应的工艺条件。反应过程主要包括4个方面;脱水;硫酸盐分解生成γ—Al_2O_3和MgO;氧化物间相互反应形成球形晶核;Mg~(2+),Al(3+)通过反应界面相互扩散成核使晶核生长。揭示了保温过程工艺参数与微粉性能的相互关系,指出了制备微粉过程的合理焙烧温度. Using sulfate as raw material, MgAl_2O_4 spinel superfine powder with excellent properties was prepared by solid state reaction at high temperature. The nucleation growth process and corresponding process conditions of spinel were studied by means of TGA / DTA, XRD and SEM. The reaction process mainly includes four aspects: dehydration; decomposition of sulfate to form γ-Al_2O_3 and MgO; mutual reaction of oxides to form spherical nuclei; diffusion of Mg ~ (2 +), Al (3+) Nucleus growth. The relationship between the process parameters and the properties of the powders was revealed, and the reasonable roasting temperature for the preparation of the powders was pointed out.