Certified Reference Materials for the Phase Transition Temperature (Curie Temperature) Based on Alumel, Nickel, and Iron Silicide

The requirements for thermal analysis instruments are increasing in terms of their metrological support with the development of scientific and technological progress in the field of metrological supervision and electronics industry. The study of determining the phase transition temperature, namely the Curie temperature, is of particular relevance for the metrological support of the applied thermal analysis instruments and traceability to the base physical units. The purpose of the research was to test the possibility of using materials based on alumel, nickel and iron silicide (trafoperm) as phase transition temperature standards for candidate materials to certified reference materials (CRMs) for the phase transition temperature traceable to the SI unit “temperature.” The procedure for measuring the phase transition temperature (Curie temperature—TC) was performed by the thermomagnetometric method using the thermal analyzer STA 449 F5 JUPITER from the State Primary Standard GET 173-2017. The determination of the CRM certified value was carried out in accordance with GOST ISO Guide 35-2015; the contributions to the uncertainty due to heterogeneity of the starting materials were evaluated; the short- and long-term stabilities of the materials were studied.