New composite metalized explosives were studied. The explosives consisted of two different types of macroscopic granular multi-component RDX-based formulations. In a 0.15 m(3) explosion chamber, fireball temperature histories for numerous cylindrical pressed and layered charges made from the composites were determined using optical spectroscopy. For comparison, charges consisting of simple mixtures instead of the composites as well TNT and RDX phlegmatized (RDXph) charges were also studied. The influence of the structure of the macroscopic granular composite, the charge type (pressed charge or layered charge with an RDXph core), oxygen availability (air or argon atmosphere) and aluminum particle size on the fireball temperature and the combustion of the aluminum powder were determined. The measured temperatures were compared with the theoretical ones calculated by assuming different activity of the aluminum fuel.