Development of software for generating and adjusting TTT diagrams

One of the main factors influencing the mechanical behavior of steel components is the rate of cooling from the austenitic field, which can lead to the formation of different microconstituents. The type of microstructure formed in a steel as a function of the cooling rate can be known, in turn, by analyzing isothermal transformation diagrams (or time-temperature-transformation diagrams, TTT) which show the time required for the decomposition of austenite to occur at a given temperature. These diagrams are characteristic of a given steel and depend to a large extent on its chemical composition. Due to the complexity involved in the experimental determination of TTT diagrams and the continuous development of new high-strength hardenable steels, since the 1970s the development of mathematical models has been sought that allow the determination of theoretical TTT diagrams based on the chemical composition of a steel. In this work, software was developed to model the TTT diagram and, based on this, determine the Jominy hardenability curve of a steel of known chemical composition.