Volatilization of chromium from AISI 441 stainless steel: Time and temperature dependence

In this work, a photospectrometric method was used to quantify chromium evaporation from the AISI 441 ferritic stainless steel. Experiments were conducted for 250 h in the temperature range of 650–850 °C to evaluate the time and temperature dependence of chromium evaporation in the initial oxidation stage. The results showed a thermally activated process with an activation energy of 218.3 kJ·mol−1 and parabolic evolution over time at 650 and 750 °C, while a change in the evaporation kinetics was observed at 850 °C, resulting in a linear trend. A diffusion-evaporation model was applied and compared to the experimental data demonstrating the role of the chromium cation diffusion on the evaporation process.