Phase diagrams are essential scientific tools for a fundamental thermodynamic material understanding. In times of increasing digitalization of the continuous casting process (CC), the availability of high-precision phase diagrams is of great importance. Especially for process control and quality prediction considerations, the knowledge of reliable thermodynamic data plays a key role, next to the numerical algorithms. These thermodynamic data should be valid for a wide range of concentrations far beyond the compositions of current steel grades to describe future alloys.
Above all, thermodynamic data need to describe highly increased concentration levels, which can result from strong micro segregation around final point of solidification. The present work provides an overview of the following selected topics: pre-identification of peritectic steels before the production by means of DSC-measurements, evaluation of microsegregation calculations for higher manganese alloyed steels by thermal analysis of “artificial” segregations and solidification calculation of phosphorus alloyed steels using a new assessment of the Fe-P system. All these examples point out the importance of “real measurements” and even why it is nowadays still necessary to critically re-examine a binary system (e.g. Fe-P) in detail.