Solid-state combustion in mechanically activated SHS systems. II. Effect of mechanical activation conditions on process parameters and combustion product composition

The effect of mechanical activation conditions in a planetary ball mill on the main parameters of SHS-processes and combustion product composition was studied for Ni + 13 wt.% Al and Ni + 45 wt.% Ti compositions. From results of experiments at elevated initial temperatures, it is concluded that because of reverse quenching, the defects produced by mechanical activation are not annealed in the heating zone and are retained in the sample until the beginning of chemical interaction in the leading zone of the SHS wave. The process of annealing of the activated samples was studied in situ on a transmission electron microscope and a synchrotron radiation diffractometer. The energy stored in the samples as a result of mechanical activation is estimated by calorimetric studies.