STUDY OF DTA METHOD EXPERIMENTAL CONDITIONS AND OF THEIR INFLUENCE ON OBTAINED DATA OF METALLIC SYSTEMS

Differential thermal analysis (DTA) is one of the methods that are suitable for obtaining of thermo-physical and thermo-dynamical data. This method enables determination of temperatures and latent heats of phase transformations of metallic systems. This paper deals with the influence of the experimental conditions settings of the used DTA method on the obtained data. The paper is focused on the study of heating rate and sample mass influence on shift of phase transformations' temperatures of Fe sample. Research was aimed at high temperature region. Melting region was studied. DTA measurements were realised using Setaram Setsys 18(TM) laboratory system. Controlled heating of Fe samples (with different mass) was conducted at the following rates: 1, 2, 5, 10, 20 K/min. On the basis of adjusted experimental conditions (different heating rates and different sample masses), the experimental data set was obtained and corresponding dependencies were derived. Using corresponding dependencies the corrections can be applied to reduce the influence of experimental conditions on studied data of investigated alloys (samples). Application of derived dependencies can substantially lead to reduction (minimization) of the influence of experimental conditions, and extrapolation to the so called "zero" mass and "zero" heating rate is possible.