Probing the intrinsic thermal reactivity mechanisms of RDX-based composites incorporated with transition metals

This paper elaborately designed and successfully prepared the mixture of RDX/transition metals including Co, Ni, Ti as well as the core-shell structured Al/Co@RDX composite. The influence of Co, Ni, and Ti powders on the thermal decomposition characteristics of RDX was explored through differential scanning calorimetry (DSC). The results indicated that in the presence of Co, Ni, and Ti, the peak temperatures of RDX decomposition display respective declines of 3.1 °C, 4.3 °C, and 5.2 °C. The thermal decomposition kinetic parameters of RDX under the action of transition metal powder were calculated by the non-isothermal kinetics method. It was observed that the Ni and Co powder exhibited remarkable catalytic activity in the decomposition process of RDX. The powder decreased the activation energies of the two-step thermal decomposition reaction of RDX by 1.2 kJ mol⁻¹ and 28.4 kJ mol⁻¹ correspondingly. Under the influence of Ni, the physical model of the second decomposition reaction of RDX changed from the autocatalytic model (AC) model to the two-dimensional nuclear growth model after random nucleation (A2) model. Furthermore, the introduction of the Co effectively elevates the combustion wave temperature of the Al@RDX by approximately 389 °C.