Cyclic Oxidation Behaviour of 1Cr–0.5Mo (T11) Boiler Tube Steel and Its Weldments in Air at 900 °C

Oxidation behaviour of weldments at elevated temperature has become an object of scientific investigation. Weldments were prepared using shielded metal arc welding and tungsten inert gas processes to weld together 1Cr–0.5Mo (T11) boiler tube steels. This paper reports the oxidation behaviour of welded and unwelded 1Cr–0.5Mo (T11) boiler tube steel specimens after exposure to air at 900 °C under cyclic condition. The thermogravimetric technique was used to establish kinetics of oxidation. X-ray diffraction and scanning electron microscopy/energy-dispersive analysis techniques were used to analyse the oxidation products. The unwelded steel showed a higher oxidation rate (in terms of weight gain) than that of welded steels.