The Influence of Structure on the Strength Properties of Casting Steel Obtained with the Use of Thermite Materials.

This paper deals with the possibility of making alloys with the use of an oxidation-reduction reaction proceeding in thermite mixtures. The variation of the fraction composition of oxidizing and reducing agents provides a possibility to obtain alloys with different compositions and properties. It has been found that the ratio between oxidizer and reducer contents has an effect on reaction parameters, the properties of generating phases and residual aluminum content in the alloy. A fairly high content of aluminum dopes the alloy, eliminates the γ-area and makes it possible to obtain the ferritic structure of the alloy. This results in the increase of internal stresses and the occurrence of intergranular cracks, which significantly decrease the physical-mechanical properties. If aluminum content in the alloy is rather small, ultimate strength may reach 800 MPa. In these circumstances, the samples fail at about 5.2 % strain. The structures of such samples are ferrite-pearlite. All the investigated samples are characterized by brittle wavy fracture, and the stressstrain diagrams do not have a distinct yield plateau. [ABSTRACT FROM AUTHOR]