目的 针对国内外对于食品用铝系发热包的研究进展与发热包产品高品质使用需求不匹配，对食品用铝系发热包放热规律进行深入研究。方法 以食品用铝系发热包为实验材料，通过红外热成像分析、氧弹量热仪测量、扫描电镜(SEM)观察等方法对铝系发热包放热规律进行探究。结果 结果表明，铝系发热包使用15 min后仍有大量发热剂未反应，内部截面呈现分层排列，由外到内分可为3层，不同层产物转化率分别为64%，100%和91.3%，且各层结构和化学性质差异明显。经分析，导致反应不完全的可能原因主要有反应产物结构阻碍水分扩散，产生的氢气阻碍外部水分的迁入，氢氧根浓度分布不均等。结论 为食品用铝系发热包的配方改良、提高食品用铝系发热包的放热品质提供了依据和指导意义。

The research progress of food heater containing aluminum powder doesn’t match the demand of high-quality use of food heater, and the in-depth study of exothermic regularity of food heater containing aluminum powder needs to be carried out. In this paper, the exothermic regularity of food heater containing aluminum powder is investigated by infrared thermal imaging analysis, oxygen bomb calorimeter measurement, scanning electron microscope (SEM) observation and other methods. The results show that a large amount of heat generating agent remained unreacted in the food heater after 15 min of use, and the internal cross-section shows a layered arrangement, which can be divided into three layers from outside to inside. The product conversion rates of different layer are 64%, 100% and 91.3%, respectively, and the structure and chemical properties of each layer are obviously different. The possible reasons for the incomplete reaction are as follows:the structure of reaction products hindered the diffusion of water; the hydrogen gas produced hindered the migration of external water; and the uneven distribution of hydroxide concentration. This study provides basis and guidance significance for the improvement of the formulation and the exothermic quality of food heater containing aluminum powder.