Oxidation behaviour of selected wrought Ni-base high temperature alloys when used as flame tube material in modern blue flame oil burners

Modern blue flame burners are equipped with a flame tube that serves for recirculation of exhaust gas and for flame stabilization. The in operation material temperature, temperature changes and atmospheres at the flame tube have been measured. Exposure tests of four Ni–Cr-alloys with different concentrations of Al have been carried out under these conditions. The breakdown of the material was connected with the failure of the oxide layer and finally with the formation of internal aluminium nitrides. An approach has been developed for predicting the failure of the oxide layer and hence of the life time of the material.