Thermodynamic and kinetic analyses of high temperature oxidation of 316L stainless steel

This study investigates the thermodynamic behavior and non-isothermal oxidation kinetics of 316L stainless steel in the temperature range of 1100 K - 1373 K, with relevance to the heat-affected zone during welding in oil and gas pipeline applications. Thermogravimetric analysis was performed at heating rates of 5, 10, 15, 20, and 25 K/min study the high-temperature oxidation kinetics of AISI 316L stainless steel welds. Kinetic analysis was conducted using Kennedy-Clark and Coats-Redfern methods as well as Friedman, Starink, Kissinger-Akahira-Sunose, and Flynn-Wall-Ozawa model-free isoconversional methods. Activation energies determined using isoconversional models ranged from 224.79 to 233.81 kJ/mol. The second-order (F2) and third-order (F3) reaction models provided the best fit to the experimental data, as confirmed by Criado master plot analysis. Thermodynamic properties (ΔH ≠ . , ΔS ≠ . , ΔG ≠ ) were also calculated for isocoversional models. FactSage thermochemical simulations revealed the formation of a dual-layer protective oxide scale primarily composed of spinel and corundum phases. These oxide layers enhance oxidation resistance at high temperatures. The findings contribute to a mechanistic and kinetic understanding of high-temperature oxidation in 316L stainless steel, supporting its reliable application in demanding oil and gas environments. • Kinetic analysis of 316LSS oxidation using isoconversional and model-fitting methods. • Identification of solid-state reaction mechanisms through Criado master plot analysis. • Thermochemical validation of oxidation products using FactSage simulations • Integrating multiple kinetic approaches to enhance the accuracy of E a determination.