Experimental investigation of the oxidation behaviour of stainless steel exposed to different air- and oxy-fuel natural gas or hydrogen combustion atmospheres and temperatures during reheating on a semi-industrial scale

In the future, steel has to be manufactured with significantly lower CO 2 emissions. Consequently, heating methods other than natural gas-fired furnaces with air as an oxidiser need to be employed. This study investigates the impact of air- and oxy-fuel combustion with natural gas and hydrogen on the scaling behaviour of EN 1.4307 (AISI 304L) stainless steel. The residual oxygen, , and the sample core temperature, 1200 °C and 1300 °C, were varied. A discontinuous gravimetric measurement method was applied, utilising ten samples of 20 × 20 × 65 mm dimensions for each set. For atmosphere generation in a semi-industrial furnace, a multi-fuel and -oxidiser burner was used. The specific mass gain was most heavily dependent on the temperature, followed by the oxidiser and fuel. In the oxy-fuel combustion mode, the presence of residual oxygen in the atmosphere and the fuel had a negligible influence. At 1200 °C, switching from natural gas/air combustion to hydrogen/air combustion resulted in a 15 % increase in the specific mass gain and, when switching from natural gas/air to oxy-fuel with natural gas or hydrogen, in a 40 % increase. • Investigation of the oxidation behaviour of EN 1.4307 (AISI 304L). • Scale formation study in a semi-industrial furnace using various fuels and oxidisers. • Impact of temperature, air-/oxy-fuel with natural gas/hydrogen and residual oxygen. • Discontinuous gravimetric method with ten samples (each 20x20x65 mm). • Determination of the scale formation kinetics using an Arrhenius-based approach.