Pack-Aliting in Thermitic Powder Mixture Obtained by Mechanical Alloying

The paper deals with the effects of the structural state modification of the main pulverulent component used for the alloying of metallic products made of steels, cast iron or nonferrous alloys, on the layers kinetics formation. The aliting process is most often done in a powdery mixtures, composed of three components: the active component providing aluminum, a neutral one with the role of dispersing the others, also having the role of blocking the sintering tendency and a halide as an activator, by cleaning the metal surfaces to be saturated. The aim of the paper is to present the ways to ensure the kinetics of the aliting layer formation, while reducing the heat treatment temperature. These could be accomplished by replacing the aluminum or ferroaluminum powder with equimassic amounts mixture of thermitic powders, consisting of ferrous oxides and aluminum powders, mechanically alloyed in high energy ball mills. Thus, it is possible to produce the aluminothermic reduction reaction in the component obtained by mechanical alloying at the same time generating notable thermal effects.