SHS of transition metal-oxide systems in a DC magnetic field: Part 2. TRXRD, thermal imaging, and chemomagnetic studies of metal-oxide systems

Abstract

The effect of an external magnetic field of 0.2 T on the SHS of a mixture of first row transition metals (Fe, Ti, Mn, Co, and Ni) and their oxides (Fe3O4, TiO2, MnO, Co3O4, and NiO) with solid-state oxidizer (NaClO4) was studied. Time resolved X-ray diffraction (TRXRD) was used to study the kinetics of intermediate product formation. Thermal imaging experiments were used to measure the reaction temperature and velocity as well as chemomagnetic signals to look for the phase transformations in combustion wave. We show that under conditions of applied field in the Fe/Fe3O4 system the fcc iron is formed during the metal-oxide transformation. For the Ni/NiO/NaClO4 system, a new metastable cubic phase eith lattice parameter 3.6 d metal-oxide systems (such as Ti, Mn, Co, and Ni) combustion are briefly described.