In the last decades, new classes of martensitic stainless steels were developed with chemical composition 0,01-0,1%C, 11-13%Cr, 2-6%Ni, with the objective of attending mainly the petroleum industry needs because they present good corrosion resistance in medium aggressive environments associated to good mechanical resistance. However, its use has been restricted by the fact of being a recent development and many of its properties are still under investigation. This work studies phase transformations by the dilatometry technique with fast cooling in order to construct the transformation time-temperature-transformation (TTT) curves in cast martensitic stainless steels and to analyze the nickel addition influence on the transformations. Based on the results the quenching and tempering conditions were selected. By continuous cooling, the austenitic transformation temperatures (Ac3) and (Ac1) and martensitic transformation temperatures (Mi) and (Mf) respectively were obtained, which provided the final martensitic structure that presents simultaneously the mechanical and corrosion resistance properties, recommended when in service.
Phases transformation; quenching; martensitic stainless steels; dilatometry
