THERMODYNAMIC STUDY OF THE ALUMINOTHERMIC AND CARBOTHERMIC PROCESS FOR THE SYNTHESIS OF CERMET FROM NICKELIFEROUS TAILS

Abstract

Introduction:
Cermets are considered advanced materials that exhibit greater versatility of applications; but the processing parameters significantly affect the final property and microstructure of the cermet system. This suggests the need to choose an appropriate synthesis route.
Objective:
To evaluate the possibility of occurrence of aluminothermic and carbothermic reactions of nickeliferous tails by means of a thermodynamic study that contributes to the development of a strategic line in the production of cermet.
Materials and Methods:
Nickeliferous tails are used as raw material to obtain cermet by means of self-propagating reactions at high temperatures. A thermodynamic study is carried out considering the behavior of free energies as a function of temperature, according to the Ellingham diagram, determining the possibility of occurrence of the reactions that govern aluminothermic and carbothermic reactions.
Results and Discussion:
The thermodynamic study shows that the predicted reactions occur spontaneously for the temperature range (300K - 1500K), except for the reactions of MgO, Cr2O3, SiO2 and TiO2.
Conclusions:
The aluminothermic reactions of the tails are spontaneous, propitiating the occurrence of self-sustained reactions; constituting a new alternative to obtain materials of high use value and high performance.