Recently published articles have enhanced the importance of understanding phase transformations in rail eutectoid steels in an attempt to improve their manufacturing and welding processes. Herein, the kinetics of isothermal phase transformations of three eutectoid steels used in railways around the world are evaluated. Computer simulations are performed to evaluate the effect of steel chemical compositions on phase transformations considering thermodynamic equilibrium conditions. Austenitizing temperatures under continuous heating and the time intervals of isothermal austenite decomposition are measured by dilatometry. The time–temperature–transformation diagrams are determined. Qualitative and quantitative microscopy techniques are applied to characterize the phase transformation products. It is shown that by applying a well‐planned heat treatment, it is possible to obtain microstructural characteristics for a standard steel as refined as those achieved for premium steels. Empirical equations proposed in the literature to predict the Bs temperatures are applied, and the experimental values are compared. Using the dilatometry data, it is possible to determine the global activation energy for austenite–bainite transformation. Results show that premium steels have higher overall activation energy for austenite–bainite decomposition than what occurs in standard. This article presents unpublished data useful for steel researchers as well for rail manufacturers and welders.

This paper presents the characterization of austenite to pearlite transformation in rail steels (premium and standard) using dilatometry. The critical transformation temperatures were measured as a cooling rate function and the obtained microstructures were qualitatively and quantitatively characterized. Aiming to study the transformation kinetics, three equations proposed by technical literature were evaluated in order to predict the transformation evolution. Experimental and calculated CCT diagrams were compared. It was concluded once the kinetics of phase transformation in rail steels is well characterized, it can be used as reference to enable suitable heat treatment to obtain pearlitic microstructures for the standard steel as refined as those of premium. The minor prior austenite grain size of the standard steel favoured the pearlite nucleation, however its highest Mn, Nb and Si contents delayed the growth stage. All equations evaluated in order to predict the kinetics of austenite to pearlite transformation under continuous cooling were satisfactory.

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This research presents an analysis of the graduates profile of The Postgraduate Program in Mineral Engineering of the Federal University of Ouro Preto (PPGEM-UFOP).To this end, a research was carried out which consisted of sending an online questionnaire to the graduates of PPGEM / UFOP. The questionnaire was answered by 79 graduates of the program. The results indicate that, in most cases, the graduates who attended the PPGEM / UFOP obtained the title of master, live in the state of Minas Gerais, studied in a public education institution during high school, graduated from UFOP and were scholarship holders. With regard to their current activities, graduates are mostly civil servants and act as teachers in public educational institutions. In addition, they consider that academic education at PPGEM was excellent and that learning had a positive influence on their professional practices.