Propagation of burning along the surface of metallic powders and their mixtures with oxides

We have experimentally investigated the process of propagation of the burning front along the surface of powders of titanium, magnesium, and mixtures of magnesium with diluents in an air atmosphere. We have determined the dependence of the velocity of propagation of the burning front along the surface of bulk metallic powders on the angle of inclination of the test bed of powder, and also the effect of additives introduced into the powders. We used several types of additives: free-burning in an air atmosphere, inert with high melting point, and low-melting-point inert powdered materials not burning in air but reacting exothermically with the metallic powders. In addition to our purely scientific interest, we also pursued a practical goal: solving problems of reducing fire and explosion hazards for production processes using or manufacturing metallic powders and mixtures based on such powders.