Experiments revealed that transient electric field intensities up to 2.5 V/cm were generated during the initial period of combustion synthesis of the ferromagnetic products before the maximum temperature was reached. This occurred when the iron particles were partially oxidized and the reaction product was mainly magnetite sFe3O4d. The electromagnetic field caused spontaneous magnetization of the product in the postcombustion zone. Magnetic field values up to 4 µT formed after the sample temperature fell below the Curie temperature and the initial reactants were completely converted to the ferromagnetic phase PbFe12O19. Increasing the volume of the samples increases the absolute residual magnetic field magnitude after cooling. We present possible mechanisms of the electromagnetic field generation during the combustion.
Martirosyan, K. S., et al. “Generation of the Transient Electrical and Spontaneous Magnetic Fields by Solid State Combustion.” Journal of Applied Physics, vol. 96, no. 8, American Institute of Physics, Oct. 2004, pp. 4632–36, doi:10.1063/1.1788845.
Journal of Applied Physics