The control of nitrogen in steel production is of great importance and is becoming increasingly relevant. As an inconspicuous but essential component of steel, nitrogen has a significant influence on material properties. This thesis deals with the development of a method for the production of nitrogen-containing steel samples in the laboratory and the thermal analysis of these steels. For laboratory sample production, a setup for adjusting the N2 partial pressure as a function of the chemical analysis of the melt was developed for a small laboratory induction furnace (high-frequency remelting plant). By means of specific Ar-N2 partial pressure mixtures, samples of the systems Fe-Cr-N, Fe-Mn-N, Fe-Nb-C-N with the desired target nitrogen content were produced as part of this work. Low-alloy steels and Fe-10%Cr alloys in particular could be produced very reliably up to the highest N contents. The second part of the work focussed on the thermal analysis of Fe-Cr-N steels using differential thermal analysis (DTA) and dynamic differential calorimetry (DSC) to determine the phase transformation temperatures in the high temperature range. Preliminary tests on a simultaneous thermal analysis (DTA-TG) with a coupled exhaust gas analysis using a mass spectrometer (QMS) were able to show that the nitrogen diffuses out of the sample from 1200°C onwards when a Fe-10Cr-0.1N alloy is heated under Ar atmospheres, thus changing the chemical analysis of the sample. An experimental concept was developed for the DSC system with a software-controlled Ar-N2 gas mixture to stabilise the N2-partial pressure during the measurement. Unfortunately, undesirable surface oxidation processes dominated due to the residual oxygen content in the nitrogen gas, meaning that reliable DSC-measurement of nitrogen-alloyed steels is not possible with the technical options currently available