Exfoliation of steam-side oxide scale in heating surface occurring during load reduction severely affects the safety of thermal power plants.Through building the finite element model for steady stress analysis
the stresses in steam-side oxide scales during unit load drop were calculated and analyzed.Ferrite alloy represented by T91 and austenitic alloy represented by TP347H were investigated in this paper. Through analyzing each of the stress components and the von Mises equivalent stress
the change of the stresses in steam-side oxide scales for both ferrite alloy and austenitic alloy during unit load drop was revealed.The possible failure modes of steam-side oxide scales for both alloys were illustrated
and it could also be concluded that the exfoliation of steam-side oxide scales for ferrite alloy and austenitic alloy was more liable to occur in the final stage and in the initial stage of load reduction respectively.