Numerical simulation of the failure behavior of steam-side oxide scale considering oxide creep and physical defects

作者：Qi, J.; Zhou, K. -Y.^*; Huang, J. -L.; Si, X. -D.

来源：Materials and Corrosion-werkstoffe Und Korrosion, 2018, 69(2): 215-226.

DOI：10.1002/maco.201709465

• crack formation
• numerical simulation
• oxide creep
• oxide scale failure behavior
• physical defects
• residual stress

The present study deals with a numerical simulation of the failure behavior of steam-side oxide scale at high temperature considering oxide creep and physical defects. An experimental observation was conducted on the oxide scale formed on T91 superheater tubes from one coal-fired plant, and the elastic-plastic finite element model (FEM) considering oxide creep was established to predict the crack load and the residual stress within oxide scale during cooling. The simulation results associated with those of the pure elastic model were used to clarify the effect of oxide creep on oxide failure. Then the FEM was applied to assess the occurrence of oxide failure as a function of physical defect length, oxide thickness, and cooling rate. The results showed that the hold period on cooling could effectively prevent oxide spallation. Interestingly, the influence of physical defect length on the through-scale crack was larger than the interface crack, while the cooling rate and oxide thickness had a more significant effect on the interface crack.

• 出版日期2018-2
• 单位东南大学