EXPERIMENTAL CORRELATION ON INFLUENCE OF THE COMPOSITION AND TEMPERATURE IN THE STEELS THERMO PHYSICAL PROPERTIES FOR ENGINEERING APPLICATIONS

In this work, a predictive method is presented to estimate the variation of three thermo physical properties (thermal diffusivity, specific heat and thermal conductivity) of 32 AISI-SAE commercial classes of rolled and annealed steels, at a working temperature from 0 to 800oC and with a composition (C, Mn, S, P, Ni, Si, Mo, Cr, V). The function adjustment method is used for the treatment and generalization of the available experimental data, obtaining an equation that provides satisfactory fits to extend its use to thermal engineering. The proposed models were verified by comparison with available experimental data. For thermal diffusivity, specific heat and thermal conductivity, the models obtained correlate with a deviation of +/- 17.6%, +/- 8.2% and +/- 16.6%, respectively. The weaker adjustment was achieved in the modelling of the thermal diffusivity of AISI-SAE 316 steel, with a maximum error of 17.6% and a mean absolute error (EMA) of 8.2% in 80.6% of the available experimental data. The best indices were obtained in the estimation of the specific heat of AISI-SAE 1078 steel, with a maximum error of 1.9% and an EMA of 1.1% in 68.3% of the available experimental samples. In all cases, the agreement of the proposed model with the available experimental data is good enough to be considered satisfactory for practical design.