The aim of the present work is to investigate the influence of certain alloying elements on the peritectic phase transformation during the continuous casting process. This work bases on recorded process data. These data originate form a mould monitoring system. The first chapter describes the abilities of the used mould monitoring system. The following chapter deals with the measurement of temperatures in the copper plate of a continuous casting mould. Furthermore specific values which can be dissipated form these measurements are described. The peritectic phase transformation in iron – carbon – alloys and multi - component alloys as well as the resulting difficulties during the continuous casting process are described in the following chapter. The practical part of the work mainly focuses on the temperature variation coefficient. It´s dependency from other process parameters is investigated. The influence of a certain alloying element is investigated for melts, that only differentiate in the contend of this alloying element, under comparably casting conditions. Finally the behaviour of the mould level is investigated for melts with different equivalent carbon contends.